2012 January 02 Monday
Trace Elements And Pancreatic Cancer Risk

A diagnosis of pancreatic cancer basically represents a notice you're going to be checking out of the Life Hotel. Bad cancer. So it is very desirable to find ways to lower the odds of getting pancreatic cancer. A new report finds some trace elements raise and lower the risk of pancreatic cancer.

A new study has found that high bodily levels of the trace elements nickel and selenium may be associated with reduced risk for pancreatic cancer, and that high levels of arsenic, cadmium and lead may increase the risk.

Avoiding toxins is usually a good idea unless you are training your body to detoxify some toxin because you expect someone to try to poison you.

I did some poking around about arsenic. In a fairly small number of areas arsenic in the water supply is a problem. Odds are you aren't in one of those areas. Arsenic comes into the diet in quite a few different ways. For example, arsenic was used to kill boll weevils in the Old South in the United States. So rice from some areas of the US has much higher arsenic in it. Louisiana rice appears to be worst with California rice as best. Imported Basmati and Jasmine rice have the lowest arsenic. But there's some dispute over how much of the arsenic in rice is of the more toxic inorganic kind. I'd like to know where some of the brand name rices come from btw. Anyone know?

In Britain fish is the biggest source of dietary arsenic.

Fish is the main source of arsenic in the UK diet.

I do not have details on which types of fish are especially high in arsenic. However, sounds like rainbow trout have pretty low arsenic levels.

In Europe arsenic shows up in a number of foodstuffs.

The main sources of inorganic arsenic intake are cereal grains and cereal based products, food for special dietary uses (e.g. algae), bottled water, coffee and beer, rice and rice-based products, fish and vegetables.

Next we come to chickens fed arsenic. It is not clear to me how much Pfizer's pulling of Roxarsone from the market cut the use of arsenic in chicken feed. Did other arsenic suppliers just replace Pfizer's product? My advice: do not eat chicken liver (where the arsenic concentrates) unless you can be certain the chicken you eat wasn't fed arsenic.

It is not clear to me what to cut out of the diet to do the easiest reduction in consumed arsenic.

By Randall Parker    2012 January 02 09:52 PM   Entry Permalink | Comments (7)
2011 April 27 Wednesday
Omega 3 Fatty Acids Increase Prostate Cancer Risk?

Starve a heart disease and feed a cancer?

SEATTLE – The largest study ever to examine the association of dietary fats and prostate cancer risk has found what's good for the heart may not be good for the prostate.

Analyzing data from a nationwide study involving more than 3,400 men, researchers at Fred Hutchinson Cancer Research Center found that men with the highest blood percentages of docosahexaenoic acid, or DHA, an inflammation-lowering omega-3 fatty acid commonly found in fatty fish, have two-and-a-half-times the risk of developing aggressive, high-grade prostate cancer compared to men with the lowest DHA levels.

Conversely, the study also found that men with the highest blood ratios of trans-fatty acids – which are linked to inflammation and heart disease and abundant in processed foods that contain partially hydrogenated vegetable oils – had a 50 percent reduction in the risk of high-grade prostate cancer. In addition, neither of these fats was associated with the risk of low-grade prostate cancer risk. The researchers also found that omega-6 fatty acids, which are found in most vegetable oils and are linked to inflammation and heart disease, were not associated with prostate cancer risk. They also found that none of the fats were associated with the risk of low-grade prostate cancer.

How does this work? Does reduced inflammation leave cancer cells less attacked by the immune system?

I hear Joe Jackson singing: Everything gives you cancer.

By Randall Parker    2011 April 27 08:05 PM   Entry Permalink | Comments (17)
2010 November 02 Tuesday
Black Raspberries Cut Colon Cancer In Mice

Fitting with my general advice to eat berries and cherries (higher in phytonutrients than the bigger fruits) black raspberries cut the incidence of colon cancer in two mouse strains.

The researchers used two strains of mice, Apc1638 and Muc2, which each have a specific gene knocked out, causing the mice to develop either intestinal tumors (in the case of Apc1638) or colitis in the case of Muc2. Colitis is an inflammation of the large intestine that can contribute to the development of colorectal cancer.

Both mouse strains were randomized to be fed either a Western-style, high-risk diet (high in fat and low in calcium and vitamin D) or the same diet supplemented with 10 percent freeze-dried black raspberry powder for 12 weeks.

The researchers found that in both mouse strains the black raspberry-supplemented diet produced a broad range of protective effects in the intestine, colon and rectum and inhibited tumor formation.

In the Apc1638 mice, tumor incidence was reduced by 45 percent and the number of tumors by 60 percent. The researchers found that black raspberries inhibited tumor development by suppressing a protein, known as beta-catenin, which binds to the APC gene.

In the Muc2 mice, tumor incidence and the number of tumors were both reduced by 50 percent, and black raspberries inhibited tumor development by reducing chronic inflammation associated with colitis.

Since colon cancer is the number 2 cancer killer of both men and women the ability to avoid it would substantially cut your risk of dying from cancer.

This report fits with a larger pattern about berries, cherries, and grapes as colon cancer risk reducers. See my previous posts Blueberries Reduce Colon Cancer Risk?, Grapes Might Reduce Colon Cancer Risk, and Purple Corn And Chokeberries Against Colon Cancer.

By Randall Parker    2010 November 02 10:15 PM   Entry Permalink | Comments (2)
2010 July 08 Thursday
Fish Oil Cuts Breast Cancer Risk?

Over a period of 6 years fish oil usage was correlated with reduced incidence of breast cancer.

PHILADELPHIA — A recent report in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research, adds to the growing evidence that fish oil supplements may play a role in preventing chronic disease.

Researchers at the Fred Hutchinson Cancer Research Center in Seattle, Wash., led by Emily White, Ph.D., a member of the public health sciences division, asked 35,016 postmenopausal women who did not have a history of breast cancer to complete a 24-page questionnaire about their use of non-vitamin, non-mineral "specialty" supplements in the Vitamins and Lifestyle (VITAL) cohort study.

After six years of follow-up, 880 cases of breast cancer were identified using the Surveillance, Epidemiology and End Results registry.

If this study's results turn out to be correct the risk reduction is substantial.

Regular use of fish oil supplements, which contain high levels of the omega-3 fatty acids, EPA and DHA, was linked with a 32 percent reduced risk of breast cancer. The reduction in risk appeared to be restricted to invasive ductal breast cancer, the most common type of the disease.

One study doesn't prove this result. But fish oil capsules are pretty cheap and probably won't hurt you. A randomized trial using vitamin D and omega 3 fatty acids that should answer this question more definitively is currently undergoing recruitment. But if you think your risk of breast cancer is substantial you might not want to wait years for the results from that study.

By Randall Parker    2010 July 08 09:40 PM   Entry Permalink | Comments (3)
2010 June 29 Tuesday
Broccoli Compound Blocks Breast Cancer Cell Growth

A compound in broccoli and brussel sprouts blocks the growth of breast cancer cells. Frequent consumption of these vegetables might lower breast cancer risk.

COLUMBUS, Ohio – Researchers at the Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute (OSUCCC-James) have discovered how a substance that is produced when eating broccoli and Brussels sprouts can block the proliferation of cancer cells.

Compelling evidence indicates that the substance, indole-3-carbinol (I3C), may have anticancer effects and other health benefits, the researchers say. These findings show how I3C affects cancer cells and normal cells.

The laboratory and animal study discovered a connection between I3C and a molecule called Cdc25A, which is essential for cell division and proliferation. The research showed that I3C causes the destruction of that molecule and thereby blocks the growth of breast cancer cells.

The molecule Cdc25A probably also serves useful purposes in people who not happen to have early stage cancer. So an obvious question arises: Will higher daily doses of indole-3-carbinol (I3C) cause undesired side effects due to, for example, inhibition of cell growth to do repairs on aging body parts?

There's a real tension between blocking undesired cellular growth and allowing or even stimulating desired and needed cell growth.

By Randall Parker    2010 June 29 11:27 PM   Entry Permalink | Comments (0)
Broccoli Compound Blocks Breast Cancer Cell Growth

A compound in broccoli and brussel sprouts blocks the growth of breast cancer cells. Frequent consumption of these vegetables might lower breast cancer risk.

COLUMBUS, Ohio – Researchers at the Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute (OSUCCC-James) have discovered how a substance that is produced when eating broccoli and Brussels sprouts can block the proliferation of cancer cells.

Compelling evidence indicates that the substance, indole-3-carbinol (I3C), may have anticancer effects and other health benefits, the researchers say. These findings show how I3C affects cancer cells and normal cells.

The laboratory and animal study discovered a connection between I3C and a molecule called Cdc25A, which is essential for cell division and proliferation. The research showed that I3C causes the destruction of that molecule and thereby blocks the growth of breast cancer cells.

The molecule Cdc25A probably also serves useful purposes in people who not happen to have early stage cancer. So an obvious question arises: Will higher daily doses of indole-3-carbinol (I3C) cause undesired side effects due to, for example, inhibition of cell growth to do repairs on aging body parts?

There's a real tension between blocking undesired cellular growth and allowing or even stimulating desired and needed cell growth.

By Randall Parker    2010 June 29 11:27 PM   Entry Permalink | Comments (0)
2010 June 20 Sunday
Vitamin B6 Cuts Lung Cancer Risk

Protect your DNA with pyridoxine (vitamin B6) and methionine.

An analysis that included nearly 400,000 participants finds that those with higher blood levels of vitamin B6 and the essential amino acid methionine (found in most protein) had an associated lower risk of lung cancer, including participants who were current or former smokers, according to a study in the June 16 issue of JAMA.

Previous research has suggested that defi­ciencies in B vitamins may increase the probability of DNA damage and subse­quent gene mutations. "Given their involvement in maintaining DNA integrity and gene ex­pression, these nutrients have a potentially important role in inhibiting cancer devel­opment, and offer the possibility of modi­fying cancer risk through dietary changes," the authors write. They add that deficiencies in nutrient levels of B vitamins have been shown to be high in many western populations.

If you eat cereal then look for fortified cereals that are especially high in B6. Also, banana, whole potatoes in skin, salmon, turkey, chicken and spinach are all good sources. Ditto garbanzo beans. Plus, liver, rabbit, hazel nuts, cashews, and peanuts are all good sources. Wheat germ is a better source than all these other foods. You can find a much more detailed break-down of B6 in foods here.

By Randall Parker    2010 June 20 11:17 PM   Entry Permalink | Comments (1)
2010 June 09 Wednesday
Polyphenols Cut Cancer Risk In Mice

Scientists are busy trying to improve the wretched lives of mice.

In what could lead to a major advance in the treatment of prostate cancer, scientists now know exactly why polyphenols in red wine and green tea inhibit cancer growth. This new discovery, published online in The FASEB Journal (http://www.fasebj.org), explains how antioxidants in red wine and green tea produce a combined effect to disrupt an important cell signaling pathway necessary for prostate cancer growth. This finding is important because it may lead to the development of drugs that could stop or slow cancer progression, or improve current treatments.

But we most want to know whether eating foods high in polyphenols or other compounds will reduce our risk of developing cancer or other diseases. The evidence on this question is less clear.

Keep in mind that cell signaling pathways exist because they serve useful functions. Chemicals from food that disrupt cellular pathways probably have downsides in addition to whatever protective properties they have.

"Not only does SphK1/S1P signaling pathway play a role in prostate cancer, but it also plays a role in other cancers, such as colon cancer, breast cancer, and gastric cancers," said Gerald Weissmann, MD, editor-in-chief of The FASEB Journal. "Even if future studies show that drinking red wine and green tea isn't as effective in humans as we hope, knowing that the compounds in those drinks disrupts this pathway is an important step toward developing drugs that hit the same target."

While less lucky mice were out struggling for survival these mice were getting fed chemicals that reduced their risk of cancer. On the other hand, these mice were bred to get cancer in the first place.

Scientists conducted in vitro experiments which showed that the inhibition of the sphingosine kinase-1/sphingosine 1-phosphate (SphK1/S1P) pathway was essential for green tea and wine polyphenols to kill prostate cancer cells. Next, mice genetically altered to develop a human prostate cancer tumor were either treated or not treated with green tea and wine polyphenols. The treated mice showed reduced tumor growth as a result of the inhibited SphK1/S1P pathway. To mimic the preventive effects of polyphenols, another experiment used three groups of mice given drinking water, drinking water with a green tea compound known as EGCg, or drinking water with a different green tea compound, polyphenon E. Human prostate cancer cells were implanted in the mice and results showed a dramatic decrease in tumor size in the mice drinking the EGCg or polyphenon E mixtures.

All the berries have polyphenols in them. So wine and green tea aren't your only food choices for potentially cutting cancer risks.

By Randall Parker    2010 June 09 10:29 PM   Entry Permalink | Comments (2)
2010 June 02 Wednesday
Calcium Poses Prostate Cancer Risk?

Higher calcium consumption might boost prostate cancer risk.

PHILADELPHIA — Among Chinese men, calcium consumption — even at relatively low levels and from non-dairy food sources such as soy, grains and green vegetables — may increase prostate cancer risk, according to results published in Cancer Research, a journal of the American Association for Cancer Research.

"Our results support the notion that calcium plays a risk in enhancing the role of prostate cancer development," said lead researcher Lesley M. Butler, Ph.D., assistant professor of epidemiology at Colorado State University, Fort Collins, Colo. "This study is the first to report an association at such low levels and among primarily non-dairy foods."

Some studies conducted in North American and European populations have linked high consumption of dairy products to an increased risk of prostate cancer. A few studies have suggested that calcium in milk is the causative factor, however the evidence is not clear.

What I wonder: Does the level of calcium needed to cause a prostate cancer risk rise with the amount of protein consumed? That might explain why a lower level of calcium consumption poses a risk in China which Western researchers only see at higher levels of calcium consumption.

This result is part of a larger body of evidence that too much calcium can boost prostate cancer risk.

Edward Giovannucci, M.D., Sc.D., professor of epidemiology and nutrition at Harvard School of Public Health, who is not associated with this study, said these results add more evidence that calcium is a causative factor of prostate cancer.

"However, there are some aspects that require further study," he said. "First, they found an association with relatively low intakes of calcium, whereas most previous studies suggested an association with high intake of calcium. Also, they found an association mostly in lean men, and whether this is true or is a chance finding requires further study."

An article in the the Journal of the American Society Nephrology (JASN) advises that too much calcium can cause calcium-alkali syndrome.

According to the authors, the obvious preventive strategy against the calcium-alkali syndrome is to limit the intake of calcium to no more than 1.2 to 1.5 grams per day. "Calcium supplements taken in the recommended amounts are not only safe but are quite beneficial. Taken to excess is the problem," said Dr. Goldfarb. "Even at the recommended dose, careful monitoring of any medication is wise and yearly determinations of blood calcium levels for those patients taking calcium supplements or vitamin D is a wise approach," he added.

Speaking as someone who takes vitamin D every day but calcium more sporadically so far the evidence for getting more vitamin D seems more compelling than the evidence for getting more calcium.

By Randall Parker    2010 June 02 11:15 PM   Entry Permalink | Comments (0)
2010 April 19 Monday
Vitamin K Cuts Non-Hodgkin Lymphoma Risk?

A reason to eat green leafies.

WASHINGTON — In the first study of vitamin K and Non-Hodgkin lymphoma risk, researchers at the Mayo Clinic campus in Minnesota have found that people who have higher intakes of vitamin K from their diet have a lower risk of developing Non-Hodgkin lymphoma. Non-Hodgkin Lymphoma is a cancer of the immune system and is the most common hematologic malignancy in the United States.

At the 101st Annual Meeting of the American Association for Cancer Research (AACR), the researchers report that the risk of developing Non-Hodgkin lymphoma was approximately 45 percent lower for participants who had vitamin K intakes in the top quartile of intake in the study (>108 ug/day), compared to participants who had intakes in the bottom quartile (<39 ug/day). This association remained after accounting for other factors such as age, sex, education, obesity, smoking, alcohol use and intake of foods with high amounts of antioxidants.

I happen to take a 2400 ug vitamin K pill (a mix of K1 and K2 forms) about once every 2 weeks. The study finds that supplemental vitamin K delivers some protective benefit as well but tops out. The press release doesn't report what level of supplementation maxes out the benefit.

Here's a good list of high vitamin K foods. Eat your kale or collard greens.

By Randall Parker    2010 April 19 11:38 PM   Entry Permalink | Comments (7)
Well Done Meats Boost Bladder Cancer Risk

Consumption of red meats and well done meats boost bladder cancer risk.

The group with the highest red-meat consumption had almost one-and-a-half times the risk of developing bladder cancer as those who ate little red meat.

Specifically, consumption of beef steaks, pork chops and bacon raised bladder cancer risk significantly. Even chicken and fish - when fried - significantly raised the odds of cancer.

The level of doneness of the meat also had a marked impact. People whose diets included well-done meats were almost twice as likely to develop bladder cancer as those who preferred meats rare.

Eat it medium rare. Do not cook at high temperatures.

People who consume the highest concentration of heterocyclic amines (HCAs) from cooking at higher temperature had even greatest risk of bladder cancer.

Further questioning of a subset of 177 people with bladder cancer and 306 people without bladder cancer showed that people with the highest estimated intake of three specific HCAs were more than two-and-a-half times more likely to develop bladder cancer than those with low estimated HCA intake.

It also helps to have the right genes. Combine high concentrations of HCAs with risky genetic variants in HCA metabolism and the result is another doubling of bladder cancer risk.

To take the investigation a step further, researchers analyzed each participant's DNA to find if it contained genetic variants in the HCA metabolism pathways that may interact with red meat intake to increase the risk of cancer.

People with seven or more unfavorable genotypes as well as high red-meat intake were at almost five times the risk of bladder cancer.

Avoiding carcinogenic foods is a more sure fire way to cut cancer risk than eating really good foods. Even with of antioxidants in your body from diet some carcinogens will slam into DNA and cause damage. Better to not eat the carcinogens in the first place.

By Randall Parker    2010 April 19 09:58 PM   Entry Permalink | Comments (1)
2010 April 07 Wednesday
Small Cancer Protection From Fruits And Vegetables?

People who hate vegetables will be happy about this report.

An analysis of dietary data from more than 400,000 men and women found only a weak association between high fruit and vegetable intake and reduced overall cancer risk, according to a study published online April 6, 2010 in the Journal of the National Cancer Institute.

It is widely believed that a diet rich in fruits and vegetables can reduce the risk of cancer. In 1990, the World Health Association recommended eating five servings of fruit and vegetables a day to prevent cancer and other diseases. But many studies since then have not been able to confirm a definitive association between fruit and vegetable intake and cancer risk.

To address the issue, Paolo Boffetta, M.D., M.P.H., of the Mount Sinai School of Medicine in New York, and colleagues analyzed data from the EPIC study (European Prospective Investigation into Cancer and Nutrition), which included 142,605 men and 335,873 women recruited for the study between 1992 and 2000. The participants were from 23 centers in ten Western European countries--Denmark, France, Germany, Greece, Italy, the Netherlands, Norway, Spain, Sweden and the United Kingdom. Detailed information on their dietary habit and lifestyle variables was obtained. After a median follow-up of 8.7 years, over 30,000 participants were diagnosed with cancer.

The authors found a small inverse association between high intake of fruits and vegetables and reduced overall cancer risk. Vegetable consumption also afforded a modest benefit but was restricted to women. Heavy drinkers who ate many fruits and vegetables had a somewhat reduced risk, but only for cancers caused by smoking and alcohol.

Other studies have found the same results. But you can still eat fruits and vegetables for your heart and arteries.

In an accompanying editorial, Walter C. Willett, M.D., Dr.P.H., of the Harvard School of Public Health, notes that "this study strongly confirms" the findings of other prospective studies that high intake of fruits and vegetables has little or no effect in reducing the incidence of cancer, although it has been shown to affect the risk of cardiovascular disease. He suggests that future research investigate the potential cancer-reducing benefits of specific fruits and vegetables and also study the effects of fruit and vegetable consumption at earlier periods of life.

It is a lot easier you reduce your risk of cardiovascular disease than to reduce your risk of cancer. We need effective cancer cures with very low side effects.

Coincidentally, another recent report finds Vitamin K as K1 found in green leafy vegetables does not cut cancer risk but Vitamin K as K2 found in cheese does cut cancer risk.

By Randall Parker    2010 April 07 12:43 AM   Entry Permalink | Comments (9)
2010 March 17 Wednesday
EPA Cuts Bowel Cancer Risk In Genetically At Risk

2 grams per day of omega 3 fatty acid EPA cut precancerous bowel polyps in those at especially high genetic risk of bowel cancer.

A purified form of an omega 3 cuts the number and size of precancerous bowel growths (polyps) in people whose genetic make-up predisposes them to bowel cancer, finds research published ahead of print in the journal Gut.

Furthermore, this particular omega 3 (eicosapentaenoic acid or EPA) seems to be as effective as the prescription medicine used to treat familial bowel polyps, but without the associated cardiovascular side effects.

The researchers base their findings on 55 patients, all of whom had the inherited genetic mutation that prompts the development of precancerous polyps in the bowel - known as familial adenomatous polyposis, or FAP for short.

People with FAP are at significantly increased risk of developing bowel cancer and require surgery to remove large sections of their bowel. Subsequently, some also need regular monitoring.

One can't tell from this study alone whether EPA would cut bowel cancer risk in the majority of people. But other studies suggest omega 3's cut risk of a few cancer types including colorectal cancer.

HOUSTON – Long-chain omega-3 fatty acids, primarily found in fish and seafood, may have a role in colorectal cancer prevention, according to results presented at the American Association for Cancer Research Frontiers in Cancer Prevention Research Conference, held Dec. 6-9, 2009, in Houston.

"Experimental data have shown benefits of long-chain omega-3 fatty acids in colorectal carcinogenesis, ranging from reduced tumor growth, suppression of angiogenesis and inhibition of metastasis," said Sangmi Kim, Ph.D., a postdoctoral fellow at the National Institute of Environmental Health Sciences, Research Triangle Park, N.C. "Our finding of inverse association between dietary intakes of long-chain omega-3 fatty acids and distal large bowel cancer in white participants adds additional support to the hypothesis."

I take a few fish oil capsules every day. I hope they are cutting my cancer risk. But since cancer risk can't be cut to zero we really need cancer cures.

By Randall Parker    2010 March 17 09:03 PM   Entry Permalink | Comments (4)
2010 March 02 Tuesday
Garlic Reduces Carcinogen Markers In Urine

Garlic might reduce your cancer risk.

COLUMBUS, Ohio – Researchers have designed a urine test that can simultaneously measure the extent of a potential carcinogenic process and a marker of garlic consumption in humans.

In a small pilot study, the test suggested that the more garlic people consumed, the lower the levels of the potential carcinogenic process were.

The research is all about body processes associated with nitrogen-containing compounds, scientists say. These processes include nitrosation, or the conversion of some substances found in foods or contaminated water into carcinogens.

Garlic appears to block the conversion of nitrates into carcinogenic nitrosamines.

About 20 percent of nitrates that are consumed convert to nitrites. A cascade of events can convert these compounds into what are called nitrosamines, and many, but not all, nitrosamines are linked to cancer.

Vegetables also contain nitrates, but previous research has suggested that the vitamin C in vegetables lowers the risk that those nitrates will convert to something toxic. Researchers suspected that nutrients in garlic could have similar antioxidant effects as vitamin C.

No surprise here. But perhaps a useful reminder to cook more with garlic?

By Randall Parker    2010 March 02 09:44 PM   Entry Permalink | Comments (0)
2010 January 25 Monday
Peanut Butter And Arugula Sandwich For Health?

Or perhaps peanut butter and kale? The greens would protect against aflatoxin.

LLNL researchers Graham Bench and Ken Turteltaub found that giving someone a small dose of chlorophyll (Chla) or chlorophyllin (CHL) — found in green leafy vegetables such as spinach, broccoli and kale — could reverse the effects of aflatoxin poisoning.

Aflatoxin is a potent, naturally occurring carcinogenic mycotoxin that is associated with the growth of two types of mold: Aspergillus flavus and Aspergillus parasiticus. Food and food crops most prone to aflatoxin contamination include corn and corn products, cottonseed, peanuts and peanut products, tree nuts and milk.

We eat hamburgers with greens on them. But how would peanut butter taste with spinach or arugula? Or perhaps some radicchio?

By Randall Parker    2010 January 25 10:22 PM   Entry Permalink | Comments (9)
2010 January 05 Tuesday
Pomegranate Cuts Breast Cancer Risk?

An in vitro study suggests that pomegranate might reduce breast cancer risk by reducing estrogen production.

Eating fruit, such as pomegranates, that contain anti-aromatase phytochemicals reduces the incidence of hormone-dependent breast cancer, according to results of a study published in the January issue of Cancer Prevention Research, a journal of the American Association for Cancer Research.

Pomegranate is enriched in a series of compounds known as ellagitannins that, as shown in this study, appear to be responsible for the anti-proliferative effect of the pomegranate.

"Phytochemicals suppress estrogen production that prevents the proliferation of breast cancer cells and the growth of estrogen-responsive tumors," said principal investigator Shiuan Chen, Ph.D., director of the Division of Tumor Cell Biology and co-leader of the Breast Cancer Research Program at City of Hope in Duarte, Calif.

Previous research has shown that pomegranate juice — punica granatum L — is high in antioxidant activity, which is generally attributed to the fruit's high polyphenol content. Ellagic acid found in pomegranates inhibits aromatase, an enzyme that converts androgen to estrogen. Aromatase plays a key role in breast carcinogenesis; therefore, the growth of breast cancer is inhibited.

What would this do to fertility? Anyone have any idea? Also, what other (perhaps mild) side effects would come from reduced estrogen production? Menopause causes problems. But pomegranate probably has a much smaller effect on estrogen production than menopause.

Have any studies been done on impact of foods on hormone levels? Do any foods appreciably lower estrogen, testosterone, progesterone, or other hormones?

By Randall Parker    2010 January 05 12:03 AM   Entry Permalink | Comments (2)
2009 December 07 Monday
Lymphoma Progression Linked To Low Vitamin D

Another reason to make sure you get enough vitamin D.

ROCHESTER, Minn. — A new study has found that the amount of vitamin D (http://www.mayoclinic.org/news2008-mchi/4904.html) in patients being treated for diffuse large B-cell lymphoma (http://www.mayoclinic.org/non-hodgkins-lymphoma/)was strongly associated with cancer progression and overall survival. The results will be presented at the annual meeting of the American Society of Hematology (http://www.hematology.org/) in New Orleans.

"These are some of the strongest findings yet between vitamin D and cancer outcome," says the study's lead investigator, Matthew Drake, M.D., Ph.D., (http://www.mayoclinic.org/bio/13726218.html) an endocrinologist at Mayo Clinic in Rochester. "While these findings are very provocative, they are preliminary and need to be validated in other studies. However, they raise the issue of whether vitamin D supplementation might aid in treatment for this malignancy, and thus should stimulate much more research."

The researchers' study of 374 newly diagnosed diffuse large B-cell lymphoma patients found that 50 percent had deficient vitamin D levels based on the commonly used clinical value of total serum 25(OH)D less than 25 ng/mL. Patients with deficient vitamin D levels had a 1.5-fold greater risk of disease progression and a twofold greater risk of dying, compared to patients with optimal vitamin D levels after accounting for other patient factors associated with worse outcomes.

It is winter time in the Northern Hemisphere. Your risk of vitamin D deficiency is greatest in the darker months. Many studies find a link between vitamin D deficiency and increased cancer risk. Here's another such study.

By Randall Parker    2009 December 07 05:55 AM   Entry Permalink | Comments (10)
2009 November 17 Tuesday
Folic Acid Boosts Cancer Risk?

A vitamin boosts cancer risk?

Patients with heart disease in Norway, a country with no fortification of foods with folic acid, had an associated increased risk of cancer and death from any cause if they had received treatment with folic acid and vitamin B12, according to a study in the November 18 issue of JAMA.

Most epidemiological studies have found inverse associations between folate (a B vitamin) intake and risk of colorectal cancer, although such associations have been inconsistent or absent for other cancers, according to background information in the article. “Experimental evidence suggests that folate deficiency may promote initial stages of carcinogenesis, whereas high doses of folic acid may enhance growth of cancer cells. Since 1998, many countries, including the United States, have implemented mandatory folic acid fortification of flour and grain products to reduce the risk of neural-tube birth defects,” the authors write. “Recently, concerns have emerged about the safety of folic acid, in particular with respect to cancer risk.”

Med Page Today has a more detailed breakdown of the statistical results.

Foods naturally high in folic acid might still be beneficial since greens, for example, have lots of other nutrients in them. But efforts to convert refined foods into high vitamin foods might be problematic. Eat your greens and beans for higher folic acid in foods that have a lot of other things going for them.

By Randall Parker    2009 November 17 09:54 PM   Entry Permalink | Comments (9)
2009 November 03 Tuesday
Lowering Cholesterol Cuts Cancer Risk?

Will cutting your cholesterol lower your cancer risk?

PHILADELPHIA – A pair of studies in Cancer Epidemiology, Biomarkers & Prevention, lay to rest the decades-long concern that lower total cholesterol may lead to cancer, and in fact lower cholesterol may reduce the risk of high-grade prostate cancer.

Demetrius Albanes, M.D., a senior investigator at the National Cancer Institute, said early studies suggested that low cholesterol could increase the risk of certain types of cancer.

"Our study affirms that lower total cholesterol may be caused by undiagnosed cancer. In terms of public health message, we found that higher levels of 'good cholesterol' (HDL) seem to be protective for all cancers, which is in line with recommendations for cardiovascular health," said Albanes.

Lowering cholesterol cuts cancer risk 15% overall.

In Platz's study, cholesterol levels had no significant effect on the entire spectrum of prostate cancer incidence, only those that were high-grade, she says.

Platz cautions that, while the group took into account factors that could bias the results, such as smoking history, weight, family history of prostate cancer, and dietary cholesterol, other things could have affected their results. One example is whether men in the study were taking cholesterol-lowering drugs at the time of the blood collections, a data point the researchers expect to analyze soon.

Results of the current study are expected to be published online Nov. 3 in the journal Cancer Epidemiology, Biomarkers & Prevention. Also in the journal is an accompanying paper from the National Cancer Institute showing that lower cholesterol in men conferred a 15 percent decrease in overall cancer cases.

If you want to lower your cholesterol go paleo and make like an ape man.

By Randall Parker    2009 November 03 10:10 PM   Entry Permalink | Comments (1)
2009 August 09 Sunday
Calorie Restriction Cuts Breast Cancer Risk In Mice

Even Intermittent Calorie Restriction (CR) cuts breast cancer risk in mice.

Previous studies have shown that intermittent calorie restriction provided greater protection from mammary tumor development than did the same overall degree of restriction, which was implemented in a chronic fashion. The researchers compared changes of a growth factor (IGF-1) in relationship to these two calorie restriction methods — chronic and intermittent — and tumor development beginning in 10-week old female mice at risk to develop mammary tumors. Their hope was to explain why intermittent restriction is more effective.

The overall degree of restriction was 25 percent reduction compared to control mice. Mammary tumor incidence was 71 percent in the control mice who ate the amount of food they wanted, 35 percent among those who were chronically restricted and only nine percent in those who intermittently restricted calories.

If one does not want to do intermittent or constant calorie restriction how best to lower insulin-like growth factor (IGF-1) and insulin in the blood? A lower glycemic index and lower carbo diet probably helps. But I wonder if any reader knows of some good tricks for lower IGF1. Maybe some dietary compound lowers it?

For the guys: It is worth noting that IGF-1 also appears to boost prostate cancer growth. Most of the dietary advice that applies to cutting breast cancer risk also applies to cutting prostate cancer risk. Couples would do well to keep that in mind.

The researchers were surprised intermittent calorie restriction helped since they expected a big IGF1 surge after calorie restriction would cancel out the benefit of brief IGF1 reduction.

The researchers were initially surprised by these findings for several reasons. First, the prevailing wisdom is that the degree of protection from calorie restriction is proportional to the degree of mammary tumor prevention. Second, they originally thought that intermittent calorie restriction might enhance tumor growth due to growth factors being secreted in response to re-feeding, Cleary said.

I did some searching on compounds that'll lower IGF-1. One study reports resveratrol lowering IGF-1 in mice on a high calorie diet. But a paper in Plos One found that while resveratrol delivered many of the benefits of calorie restriction (CR) it didn't lower IGF-1 in mice.

Some of the phenotypes that are observed in animals with altered IGF-1 or insulin signaling are also observed in CR mice, such as reduced levels of IGF-1, insulin and glucose [18]. To investigate if resveratrol inhibits transcriptional profiles of aging and mimics CR through an endocrine mechanism, we measured glucose, T3, insulin, IGF-1 and GH in five month-old control, CR and resveratrol fed mice. Following two months of dietary intervention, we observed reduced IGF-1 levels in CR mice, but not in resveratrol treated mice (Figure 2B). We did not observe significant alterations in any other hormones examined. Surprisingly, because we observed a large overlap of transcriptional shifts induced by resveratrol and CR in all organs examined, our findings also suggest that a large component of the transcriptional program induced by CR may be independent of CR-mediated alterations in plasma IGF-1, or insulin. This conclusion is supported by the finding that dwarfism and CR may impact lifespan through independent mechanisms [19], and the finding that GH deficiency and CR display minimal overlap at the gene expression level [20].

Can any flavonoids lower IGF-1?

Update: Cancers can mutate to become insensitive to CR.

“Our findings indicate that each tumor cell bears a signature that determines whether or not that cell will be affected by dietary restriction,” says Nada Kalaany, first author of the paper and a postdoctoral researcher in the lab of Whitehead Member David Sabatini. “We think that mutations in the PI3K pathway are a major determinant of the sensitivity of tumors to dietary restriction.”

Do not wait until late in life to clean up your diet. By then the damage has already accumulated.

By Randall Parker    2009 August 09 09:36 AM   Entry Permalink | Comments (5)
2009 June 26 Friday
Genetic Variants Govern Harm Or Benefit Of Selenium For Prostate

Guys worried about prostate cancer risk: Should you take selenium or eat Brazil nuts to boost your blood selenium? The benefits or risks of selenium depend at least in part on genetic variants of the enzyme manganese superoxide dismutase (SOD2).

BOSTON--Higher selenium levels in the blood may worsen prostate cancer in some men who already have the disease, according to a study by researchers at Dana-Farber Cancer Institute the University of California, San Francisco.

This is a pretty dramatic demonstration of the future value of nutrigenomics where you'll be able to tailor your diet to fit your genetic endowment. What would be a beneficial diet for some men looks to be harmful to others.

25% of the population have two copies of the A variant of the manganese superoxide dismutase (SOD2) gene and for them higher selenium probably lowers their risk of prostate cancer. But those with one or two copies of the V version of the gene are at greater risk from prostate cancer if they get more selenium.

A higher risk of more-aggressive prostate cancer was seen in men with a certain genetic variant found in about 75 percent of the prostate cancer patients in the study. In those subjects, having a high level of selenium in the blood was associated with a two-fold greater risk of poorer outcomes than men with the lowest amounts of selenium. By contrast, the 25 percent of men with a different variant of the same gene and who had high selenium levels were at 40 percent lower risk of aggressive disease. The variants are slightly different forms of a gene that instructs cells to make manganese superoxide dismutase (SOD2), an enzyme that protects the body against harmful oxygen compounds.

This result calls into question the wisdom of taking selenium if you already have prostate cancer.

The research findings suggest that "if you already have prostate cancer, it may be a bad thing to take selenium," says Philip Kantoff, MD, director of Dana-Farber's Lank Center for Genitourinary Oncology and senior author of the study that is published by the Journal of Clinical Oncology on its website now and later will be in a print journal. The lead author is June Chan, ScD, of the University of California, San Francisco.

So if you have SOD2 in AA form you probably would benefit from higher selenium. Personal genetic profiles are starting to become useful in daily life.

Simply having a high level of selenium was associated with a slightly elevated risk of aggressive prostate cancer. But the risk was much more strongly affected by the interaction of selenium levels and whether the patient had a certain variant of the SOD2 gene. Men with the highest selenium levels and the "AA" form of the SOD2 gene were 40 percent less likely to have been diagnosed with aggressive prostate cancer than the men with same gene form but low levels of selenium.

But for men carrying the "V" form of the gene, selenium had the opposite effect. In these men, those with the highest levels of selenium in their blood were about twice as likely to have an aggressive type of prostate cancer as their counterparts with low selenium levels, says Kantoff, who is also a professor of medicine at Harvard Medical School.

This isn't the only gene which influences whether a food is beneficial or harmful. Some people have genes that cause them to retain too much iron. Others lack enough of the enzyme lactase for breaking down lactose sugar in milk. We aer going to see a big flood of genetic research findings about many more genetic variants that change which foods best fit individual needs.

By Randall Parker    2009 June 26 11:52 PM   Entry Permalink | Comments (0)
2009 June 24 Wednesday
Obesity Linked To Pancreatic Cancer Risk

Heavier people get pancreatic cancer at younger ages.

HOUSTON - In reviewing the weight history of pancreatic cancer patients across their life spans, researchers at The University of Texas M. D. Anderson Cancer Center have determined that a high body mass index in early adulthood may play a significant role in an individual developing the disease at an earlier age.

The study, published in the June 24 issue of the Journal of the American Medical Association, also found that patients who are obese the year before diagnosis have a poorer outcome than those who are not.

While excess weight is a known risk factor associated with pancreatic cancer, before now, few studies have looked at patients' body mass index (BMI) throughout their lifetime rather than simply at adulthood and/or year of disease diagnosis.

Of course there's the possibility that genes that boost obesity risk also boost cancer risk. Or heavier weight reduces exercise that somehow boosts cancer risk. But there's a decent chance here that obesity more directly boosts pancreatic cancer risk. Eat accordingly.

The researchers found that individuals who were overweight (a BMI of 25-29.9) from the ages of 14 to 39 years or obese (a BMI of 30 or greater) from the ages of 20 to 49 years had an associated increased risk of pancreatic cancer, independent of diabetes status. The association between average BMI (per 5-unit increase) and risk of pancreatic cancer was stronger in men than in women. The association was statistically significant for each age group from 14 to 69 years in men but only from ages 14 to 39 years in women. The estimated association of average BMI (per 5-unit increase) with cancer risk also was slightly stronger in ever smokers than in never smokers. It was estimated that 10.3 percent of never smokers and 21.3 percent of ever smokers had pancreatic cancer attributable to being overweight or obese at an early age prior to cancer diagnosis (i.e., from the ages of 14-59 years).

Individuals who were overweight or obese from the ages of 20 to 49 years had an earlier onset of pancreatic cancer by 2 to 6 years (median [midpoint] age of onset was 64 years for patients with normal weight, 61 years for overweight patients, and 59 years for obese patients). Compared with those with normal body weight and after adjusting for all clinical factors, individuals who were overweight or obese from the ages of 30 to 79 years or in the year prior to recruitment had reduced overall survival of pancreatic cancer regardless of disease stage and tumor resection status.

The problem with applying this result to your life is that most dieters gain back their lost weight. Conscious weight control is very difficult and most people fail at it.

In my mind the main purpose of cancer risk reduction is to delay getting cancer until when it becomes curable.

Interventional studies provide stronger evidence than population studies that just find correlations bewteen two factors. Well, with that thought in mind if you doubt that weight reduction can cut cancer risk consider a new study from Sahlgrenska University Hospital in Sweden,which found that in women (though curiously not in men) bariatric surgery (e.g. stomach staples) cut the incidence of cancer in women.

New evidence suggests that obese women could lower their risk of cancer over 40 percent by undergoing weight-loss operations that involve stapling the stomach or small intestine.

So a good appetite suppressant drug will probably some day cut the incidence of cancer.

Update: Parenthetically, the mortality rates from bariatric surgery are now pretty low.

DURHAM, N.C. -- Advances in weight-loss surgery have made it as safe as any routine surgical procedure, according to a Duke University Medical Center researcher who reviewed data from nearly 60,000 patients and found it resulted in low complication and mortality rates.

The analysis, compiled from the largest repository of bariatric surgery patients ever recorded, indicates complication rates hover around 10 percent – with the most common complaint being nausea/vomiting. Total mortality rate was under one percent (0.135%) with 78 deaths reported among 57,918 patients.

Note that surgeons who perform a procedure frequently make fewer mistakes. So if you are considering bariatric surgery look for a surgeon who specializes in it.

By Randall Parker    2009 June 24 07:15 PM   Entry Permalink | Comments (0)
2009 June 23 Tuesday
Green Tea Cuts Prostate Cancer Risk?

A couple of studies suggest green tea delivers a protective effect against prostate cancer.

Cardelli and colleagues conducted this open-label, single-arm, phase II clinical trial to determine the effects of short-term supplementation with green tea's active compounds on serum biomarkers in patients with prostate cancer. The biomarkers include hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF) and prostate specific antigen (PSA). HGF and VEGF are good prognostic indicators of metastatic disease.

The study included 26 men, aged 41 to 72 years, diagnosed with prostate cancer and scheduled for radical prostatectomy. Patients consumed four capsules containing Polyphenon E until the day before surgery — four capsules are equivalent to about 12 cups of normally brewed concentrated green tea, according to Cardelli. The time of study for 25 of the 26 patients ranged from 12 days to 73 days, with a median time of 34.5 days.

Findings showed a significant reduction in serum levels of HGF, VEGF and PSA after treatment, with some patients demonstrating reductions in levels of greater than 30 percent, according to the researchers.

Cardelli and colleagues found that other biomarkers were also positively affected. There were only a few reported side effects associated with this study, and liver function remained normal.

Results of a recent year-long clinical trial conduced by researchers in Italy demonstrated that consumption of green tea polyphenols reduced the risk of developing prostate cancer in men with high-grade prostate intraepithelial neoplasia (HGPIN).

Mushrooms,, promegranate juice and vitamin D might all cut prostate cancer risk. Cutting carbs might help. You can read about still more dietary factors for influencing prostate cancer risk.

By Randall Parker    2009 June 23 11:12 PM   Entry Permalink | Comments (2)
2009 June 02 Tuesday
Diet And Lifestyle Risk Factors For Bowel Cancer

Keep your weight down, drink less alcohol, cut out cigarette smoking, and exercise to cut your bowel cancer risks.

A new global study has found that lifestyle risk factors such as alcohol consumption and cigarette smoking are important risk factors for bowel cancer. Researchers have shown that people who consume the largest quantities of alcohol (equivalent to > 7 drinks per week) have 60% greater risk of developing the cancer, compared with non-drinkers.

Smoking, obesity and diabetes were also associated with a 20% greater risk of developing bowel cancer - the same risk linked with consuming high intakes of red and processed meat.

The researchers analyzed a large number of existing studies to look for patterns.

The benefits of fruits and vegetables seemed small.

On a positive note, researchers also demonstrated that physical activity lowered an individual's risk of the disease but surprisingly, there was little evidence to indicate that high intakes of fruit and vegetables were protective against bowel cancer.

Avoiding cancer is more a game of removing risk factors than adding protective factors. Take away toxins and you'll live longer.

By Randall Parker    2009 June 02 10:55 PM   Entry Permalink | Comments (1)
2009 May 30 Saturday
New Theory On Vitamin D Cancer Protection Mechanism

UCSD epidemiologist Cedric Garland theorizes vitamin D prevents cells in the early stage of cancer from breaking off healthy communications with neighboring cells. Don't let those wayward cells withdraw from cellular society, become alienated, and sociopathic. Keep them involved with good neighbors that'll talk sense to them.

In studying the preventive effects of vitamin D, researchers at the Moores Cancer Center at the University of California, San Diego, have proposed a new model of cancer development that hinges on a loss of cancer cells' ability to stick together. The model, dubbed DINOMIT, differs substantially from the current model of cancer development, which suggests genetic mutations as the earliest driving forces behind cancer.

"The first event in cancer is loss of communication among cells due to, among other things, low vitamin D and calcium levels," said epidemiologist Cedric Garland, DrPH, professor of family and preventive medicine at the UC San Diego School of Medicine, who led the work. "In this new model, we propose that this loss may play a key role in cancer by disrupting the communication between cells that is essential to healthy cell turnover, allowing more aggressive cancer cells to take over."

Reporting online May 22, 2009 in the Annals of Epidemiology, Garland suggests that such cellular disruption could account for the earliest stages of many cancers. He said that previous theories linking vitamin D to certain cancers have been tested and confirmed in more than 200 epidemiological studies, and understanding of its physiological basis stems from more than 2,500 laboratory studies.

"Competition and natural selection among disjoined cells within a tissue compartment, such as might occur in the breast's terminal ductal lobular unit, for example, are the engine of cancer," Garland said. "The DINOMIT model provides new avenues for preventing and improving the success of cancer treatment."

Garland went on to explain that each letter in DINOMIT stands for a different phase of cancer development. "D" stands for disjunction, or loss of intercellular communication; "I," for initiation, where genetic mutations begin to play a role; "N" for natural selection of the fastest-reproducing cancer cells; "O" for overgrowth of cells; "M" for metastasis, when cancer cells migrate to other tissues, where cancer can kill; "I" refers to involution, and "T" for transition, both dormant states that may occur in cancer and potentially be driven by replacing vitamin D.

My interpretation is that if this theory is correct then vitamin D intervenes at a fairly early stage of cancer development. The competition helps growth-promoting mutations to get selected for. That competition must be prevented at the earliest stage possible to reduce or delay the accumulation of growth-promoting mutations.

While there is not yet definitive scientific proof, Garland suggests that much of the evolutionary process in cancer could be arrested at the outset by maintaining vitamin D adequacy. "Vitamin D may halt the first stage of the cancer process by re-establishing intercellular junctions in malignancies having an intact vitamin D receptor," he said.

According to Garland, other scientists have found that the cells adhere to one another in tissue with adequate vitamin D, acting as mature epithelial cells. Without enough vitamin D, they may lose this stickiness along with their identity as differentiated cells, and revert to a stem cell-like state.

Garland suggests 2000 IU/day of vitamin D supplementation.

Garland said that diet and supplements can restore appropriate vitamin D levels, and perhaps help in preventing cancer development. "Vitamin D levels can be increased by modest supplementation with vitamin D3 in the range of 2000 IU/day," he noted.

That'll probably cut the risks of Alzheimer's and other diseases too.

By Randall Parker    2009 May 30 03:02 PM   Entry Permalink | Comments (3)
2009 May 27 Wednesday
Cut Carbos For Longer Prostate Cancer Survival?

Got prostate cancer? A change of diet might help.

DURHAM, N.C. -- Restricting carbohydrates, regardless of weight loss, appears to slow the growth of prostate tumors, according to an animal study being published this week by researchers in the Duke Prostate Center.

"Previous work here and elsewhere has shown that a diet light in carbohydrates could slow tumor growth, but the animals in those studies also lost weight, and because we know that weight loss can restrict the amount of energy feeding tumors, we weren't able to tell just how big an impact the pure carbohydrate restriction was having, until now," said Stephen Freedland, M.D., a urologist in the Duke Prostate Center and lead investigator on this study.

The researchers believe that insulin and insulin-like growth factor contribute to the growth and proliferation of prostate cancer, and that a diet devoid of carbohydrates lowers serum insulin levels in the bodies of the mice, thereby slowing tumor growth, Freedland said.

In miche the no-carbo diet made a big difference in survival times.

"The mice that were fed a no-carbohydrate diet experienced a 40 to 50 percent prolonged survival over the other mice," Freedland said.

This brings up an obvious question: Will a low-carbo diet cut the risks of developing prostate cancer in the first place? Also, will such a diet lower the risks of developing other types of cancer?

By Randall Parker    2009 May 27 12:29 AM   Entry Permalink | Comments (2)
2009 April 28 Tuesday
Drugs And Vitamins Against Prostate Cancer

GlaxoSmithKline PLC's Avodart (dual 5-alpha-reductase inhibitor dutasteride which inhibits the conversion of testosterone into dihydrotesterone) cuts the risk of prostate cancer (and the same drug is also used to slow hair loss btw).

In the study, which involved 8,231 patients with increased risk of prostate cancer, 22.5% of men taking Avodart were diagnosed with prostate cancer after four years, compared with 29% who were taking a placebo.

But it did not cut the incidence of high grade tumors. Maybe those cancers were already present when Avodart dosing was started. Dutasteride might be better than finasteride (Proscar) for this purpose.

But wait, there's more. A big Mayo Clinic study found that statins seem to reduce the incidence of prostate cancer, erectile dysfunction and prostate enlargement.

Vitamin D might slow the development of existing prostate cancer.

Out of 26 men with recurrent prostate cancer, who took a daily dose of vitamin D2 bought from the chemist, five responded to the treatment.

In two the PSA level, fell by more than half, in two by 25-50% and in one man it fell by less than 25%.

Another small study found that pomegranate juice slows prostate cancer growth.

The two-stage clinical trial followed a total of 48 participants over six years. Eligible participants had a rising PSA after surgery or radiotherapy, a PSA greater than 0.2 ng/ml and less than 5 ng/ml and a Gleason score of 7 or less. These patients were treated by drinking eight ounces of pomegranate juice daily. Currently, in the sixth year of treatment, active patients who remain on the study have a median total follow-up of 56 months. These participants continue to experience a significant increase in PSA doubling time following treatment, from a mean of 15.4 months at baseline to 60 months post-treatment, with a median PSA slope decrease of 60 percent, 0.06 to 0.024.

One problem: I've yet to see pomegranate juice in a store.

So guys you've got drugs, a vitamin, and a juice to cut your risks of dying from prostate cancer.

By Randall Parker    2009 April 28 12:47 AM   Entry Permalink | Comments (9)
2009 April 22 Wednesday
Walnuts Cut Breast Cancer In Mice

Mice get all the important answers before humans do.

DENVER – Walnut consumption may provide the body with essential omega-3 fatty acids, antioxidants and phytosterols that reduce the risk of breast cancer, according to a study presented at the American Association for Cancer Research 100th Annual Meeting 2009.

Elaine Hardman, Ph.D., associate professor of medicine at Marshall University School of Medicine, said that while her study was done with laboratory animals rather than humans, people should heed the recommendation to eat more walnuts.

"Walnuts are better than cookies, french fries or potato chips when you need a snack," said Hardman. "We know that a healthy diet overall prevents all manner of chronic diseases."

Hardman and colleagues studied mice that were fed a diet that they estimated was the human equivalent of two ounces of walnuts per day. A separate group of mice were fed a control diet.

Standard testing showed that walnut consumption significantly decreased breast tumor incidence, the number of glands with a tumor and tumor size.

"These laboratory mice typically have 100 percent tumor incidence at five months; walnut consumption delayed those tumors by at least three weeks," said Hardman.

Aside from the fats what are the other compounds in nuts that are good for you? Magnesium comes to mind. In fact, magnesium is on my short list of nutrients I get from pills.

I'd like to see this experiment repeated with other types of nuts and with mixes of fats that mirror the fat composition of walnuts and other nuts. Such experiments would hep to tease out the relative health value of the omega-3 alpha-linolenic acid (ALA) in walnuts (they are way higher in ALA than other nuts) versus other compounds in the nuts. If it turns out ALA plays a big beneficial role in cutting breast cancer risk then I'd like to see the series of experiments extended to fish omega 3 fatty acids DHA and EPA.

By Randall Parker    2009 April 22 11:27 PM   Entry Permalink | Comments (0)
2009 April 06 Monday
Apples Cut Breast Cancer Risk?

An apple a day keeps the breast cancer away.

Six studies published in the past year by a prominent Cornell researcher add to growing evidence that an apple a day -- as well as daily helpings of other fruits and vegetables -- can help keep the breast-cancer doctor away.

In one of his very recent papers, published in the Journal of Agricultural and Food Chemistry (57:1), Rui Hai Liu, Cornell associate professor of food science and a member of Cornell's Institute for Comparative and Environmental Toxicology, reports that fresh apple extracts significantly inhibited the size of mammary tumors in rats -- and the more extracts they were given, the greater the inhibition.

"We not only observed that the treated animals had fewer tumors, but the tumors were smaller, less malignant and grew more slowly compared with the tumors in the untreated rats," said Liu, pointing out that the study confirmed the findings of his preliminary study in rats published in 2007.

In his latest study, for example, he found that a type of adenocarcinoma -- a highly malignant tumor and the main cause of death of breast-cancer patients, as well as of animals with mammary cancer -- was evident in 81 percent of tumors in the control animals. However, it developed in only 57 percent, 50 percent and 23 percent of the rats fed low, middle and high doses of apple extracts (the equivalent of one, three and six apples a day in humans), respectively, during the 24-week study.

Mushrooms and green tea will probably also cut breast cancer risk.

By Randall Parker    2009 April 06 11:35 PM   Entry Permalink | Comments (0)
2009 March 25 Wednesday
Omega 3 Fatty Acids Might Cut Prostate Cancer Risk

Correlation is not causation. But people who eat foods high in omega 3 fatty acids appear to get less aggressive prostate cancer.

March 24, 2009 -- Men who eat salmon and other fish high in omega-3 fatty acids on a regular basis have a decreased risk for developing advanced prostate cancer, new research suggests.

The association was most pronounced among men believed to have a genetic predisposition for developing aggressive prostate cancer.

Men in the study who ate one or more servings of fatty fish a week were found to have a 63% lower risk for developing aggressive prostate cancer than men who reported never eating fish, study co-researcher John S. Witte, PhD, tells WebMD.

The benefit might flow from blocking inflammation caused by a COX-2 gene variant.

A similar trend was seen for different levels of shellfish intake. Shellfish also contains omega-3 fatty acids. Omega-3 intake also had a major impact on the effect of a hazardous variant of the COX-2 gene, which promotes inflammation and is known to be linked to prostate cancer.

Men with the variant have a more than five-fold increased risk of aggressive prostate cancer. But a high consumption of oily fish effectively wiped out this risk factor.

A half gram of omega 3 looks like enough to do the trick for people who have a high risk genetic variant of COX-2. So maybe the 3 fish oil capsules I take per day might be sufficient.

The researchers then assessed the effect of omega-3 fatty acid among men with the variant rs4647310 in COX-2, a known inflammatory gene. Men with low long chain omega-3 fatty acid intake and this variant had a more than five-fold increased risk of advanced prostate cancer. But men with high intake of omega-3 fatty acids had a substantially reduced risk, even if they carried the COX-2 variant.

"The COX-2 increased risk of disease was essentially reversed by increasing omega-3 fatty acid intake by a half a gram per day," said Witte. "If you want to think of the overall inverse association in terms of fish, where omega-3 fatty acids are commonly derived, the strongest effect was seen from eating dark fish such as salmon one or more times per week."

Here is a more technical discussion of the results.

For an additional potential prostate cancer risk reduction eat fish with mushrooms.

By Randall Parker    2009 March 25 10:34 PM   Entry Permalink | Comments (0)
2009 March 17 Tuesday
Mushrooms And Green Tea Cut Breast Cancer Risk?

A mushroom a day keeps the oncologist away.

The researchers found that women who consumed the most fresh mushrooms, 10 grams or more daily, were roughly two thirds less likely to develop breast cancer than those who consumed no mushrooms. Furthermore, those who ate 4 grams or more of dried mushrooms daily halved their cancer risk compared with women who ate no mushrooms.

The results showed that mushroom eaters who also consumed green tea everyday had only 11-18 percent the risk of breast cancer of women who consumed neither. However, the researchers emphasize that the study does not prove a cause-and-effect relationship.

On the one hand I argue against trying to eat a few superfoods as a substitute for a generally good diet. On the other hand, these are dramatic results. Keep in mind though, that lots of other diseases kill people. You can't just focus on cutting the risks of one or two diseases. Here's the abstract.

Mushroom extract is getting tested in California to see if it'll cut the recurrence of breast cancer.

Last month scientists in California began a trial to see if taking a mushroom extract twice a day for a month helps breast cancer survivors remain free of the disease.

Mushrooms aren't just for girls. Mushrooms might also cut the risk of prostate cancer too.

In their quest to find new ways to fight cancer, researchers are increasingly turning to nature. They’re discovering that many of the vegetables we regularly consume in our diet —notably mushrooms—are potent cancer killers. A new study in the journal Nutrition and Cancer finds that the white button mushroom is particularly effective against prostate cancer.

A number of different mushroom species have been investigated for their cancer-fighting properties. “I think mushrooms, and especially medicinal mushrooms, are being used to prevent cancer because they potentially have the ability to affect immune function in our bodies,” says study author Shiuan Chen, PhD, Professor and Director of the Division of Tumor Cell Biology at the Beckman Research Institute of the City of Hope in Duarte, California.

I would like to know whether cooking cuts the potency of mushrooms as cancer preventatives. Anyone have any idea?

By Randall Parker    2009 March 17 12:25 AM   Entry Permalink | Comments (6)
2009 March 14 Saturday
Folic Acid Prostate Cancer Risk?

Whether you get your folic acid in foods or supplement pills might determine whether you get a net benefit or net harm from it.

A study led by researchers at the University of Southern California (USC) found that men who took a daily folic acid supplement of 1 mg daily had more than twice the risk of prostate cancer compared with men who took a placebo.

The finding came from a secondary analysis of the Aspirin/Folate Polyp Prevention Study (AFPP), a placebo-controlled randomized trial to determine the impact of aspirin and folic acid on colon polyps in men and women who were at high risk for the disease. The results appear in the March 10 online issue of the Journal of the National Cancer Institute.

Folic acid (folate) is a B vitamin found in many vegetables, beans, fruits and whole grains. While evidence of its ability to reduce neural tube defects in infants while taken by the mother before or during pregnancy has been well documented, its effects on other conditions are unclear.

Folate delivers many benefits. But that doesn't mean all its effects are beneficial.

We know that adequate folate levels are important in the prevention of several cancer types, cardiovascular and neurological diseases,” says lead author Jane Figueiredo, Ph.D., assistant professor of preventive medicine at the Keck School of Medicine of USC. “However, little has been known about its role in prostate cancer. Our objective was to investigate the relationship between folic acid supplements and dietary folate and risk of prostate cancer.”

Supplementary folic acid appears to boost risk of advanced polyps in the colon. Not good. So far studies have found conflicting results of folic acid supplements on prostate cancer risk.

The AFPP study was conducted between 1994 and 2006 and found that aspirin reduced the risk of colon polyps while folic acid had a negative effect and increased the risk of advanced and multiple polyps. The first analysis did not address the impact of folic acid supplements on prostate cancer risk. Previous observational studies have been inconsistent. Some studies suggest that increased folate in the diet or in supplements might actually lower the risk of prostate cancer, and others have suggested no effect or even a potential harmful effect.

So we do not know the answer from one study. But there's a prudent response: eat foods (beans, green leafy vegetables) that are higher in folate rather than pills. Those foods are beneficial for other reasons.

The difference between placebo and folic acid supplements was large. But even the 3.3% rate of prostate cancer in the placebo group is too high. We need cures for cancer.

In the secondary analysis, researchers looked at prostate cancer incidence among 643 men who were randomly assigned to 1 mg daily folic acid supplements or placebo in the AFPP study and who enrolled in an extended follow-up study. The estimated prostate cancer risk was 9.7 percent at 10 years in men assigned to folate, compared with 3.3 percent in men assigned to placebo.

They found a benefit from folate in foods.

By contrast, dietary folate intake and plasma folate showed a trend toward reduced risk of prostate cancer, although the difference did not reach statistical significance. It remains unclear why dietary and circulating folate among non-multivitamin users may be inversely associated with risk, Figueiredo says.

The synthetic form is more bioavailable. But this isn't just a matter of total dose. The pill form is going to absorb into the bloodstream more rapidly, especially if taken on an empty stomach. The problem might come from a spike in blood folate levels where the extra folate drives, for example, methylation of DNA and causes gene regulatory changes.

“The synthetic form of folate, folic acid, found in supplements, is more bioavailable compared to folate from dietary sources and we know the amount of folate available is critical,” she says. “Adequate levels of folate may be beneficial, but too much folate is unlikely to be beneficial.”

A larger study is needed to confirm or dismiss these results. What I'd like to see in a larger study: 3 groups. The first group would get placebo, the second group folic acid, the third group folic acid in a time release form. The time release form would tell us if the problem is due to a spike in levels. Maybe a fourth group is needed to get a different form of folate.

Alternatively, these results may be due to chance, and replication by other studies is needed, she notes.

Eat better food. That's your best bet.

By Randall Parker    2009 March 14 09:43 AM   Entry Permalink | Comments (6)
2009 February 27 Friday
Alcohol Boosts Cancer Risk In Women

1 drink of alcohol per day is enough to substantially boost cancer risks in women.

Low to moderate alcohol consumption among women is associated with a statistically significant increase in cancer risk and may account for nearly 13 percent of the cancers of the breast, liver, rectum, and upper aero-digestive tract combined, according to a report in the February 24 online issue of the Journal of the National Cancer Institute.

With the exception of breast cancer, little has been known about the impact of low to moderate alcohol consumption on cancer risk in women.

To determine the impact of alcohol on overall and site-specific cancer risk, Naomi Allen, D.Phil., of the University of Oxford, U.K., and colleagues examined the association of alcohol consumption and cancer incidence in the Million Women Study, which included 1,280,296 middle-aged women in the United Kingdom. Participants were recruited to the study between 1996 and 2001. Researchers identified cancer cases through the National Health Service Central Registries.

Women in the study who drank alcohol consumed, on average, one drink per day, which is typical in most high-income countries such as the U.K. and the U.S. Very few drank three or more drinks per day. With an average follow-up time of more than 7 years, 68,775 women were diagnosed with cancer.

Alcohol boosts risks for an assortment of cancers.

Each additional alcoholic drink regularly consumed per day was associated with 11 additional breast cancers per 1000 women up to age 75; one additional cancer of the oral cavity and pharynx; one additional cancer of the rectum; and an increase of 0.7 each for esophageal, laryngeal, and liver cancers. For these cancers combined, there was an excess of about 15 cancers per 1000 women per drink per day. (The background incidence for these cancers was estimated to be 118 per 1000 women in developed countries.)

Less alcohol could be combined with more calcium to lower cancer risks.

Women with higher intake of calcium appear to have a lower risk of cancer overall, and both men and women with high calcium intakes have lower risks of colorectal cancer and other cancers of the digestive system, according to a report in the February 23 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.

Calcium is known to benefit bone health, according to background information in the article. Because of this, the Institute of Medicine recommends 1,200 milligrams of calcium for adults age 50 and older, and the 2005 dietary guidelines for Americans recommend 3 cups per day of low-fat or fat-free dairy products. Studies of dairy products, calcium intake and cancer have revealed different results for different cancer sites.

The top fifth in calcium consumption are a much less risk for cancer.

"In both men and women, dairy food and calcium intakes were inversely associated with cancers of the digestive system," the authors write. The one-fifth of men who consumed the most calcium through food and supplements (about 1,530 milligrams per day) had a 16 percent lower risk of these types of cancer than the one-fifth who consumed the least (526 milligrams per day). For women, those in the top one-fifth of calcium consumption (1,881 milligrams per day) had a 23 percent lower risk than those in the bottom one-fifth (494 milligrams per day). The decreased risk was particularly pronounced for colorectal cancer. Calcium and dairy food intake was not associated with prostate cancer, breast cancer or cancer in any other anatomical system besides the digestive system.

By Randall Parker    2009 February 27 12:52 AM   Entry Permalink | Comments (10)
2009 February 19 Thursday
Apples Cut Rat Breast Cancer Incidence

An apple a day keeps the oncologist away.

Six studies published in the past year by a Cornell researcher add to growing evidence that an apple a day -- as well as daily helpings of other fruits and vegetables -- can help keep the breast-cancer doctor away.

You might need to eat 6 apples a day to get the full benefit.

In one of his recent papers, published in the Journal of Agricultural and Food Chemistry (57:1), Rui Hai Liu, Cornell associate professor of food science and a member of Cornell's Institute for Comparative and Environmental Toxicology, reports that fresh apple extracts significantly inhibited the size of mammary tumors in rats -- and the more extracts they were given, the greater the inhibition.

"We not only observed that the treated animals had fewer tumors, but the tumors were smaller, less malignant and grew more slowly compared with the tumors in the untreated rats," said Liu, pointing out that the study confirmed the findings of his preliminary study in rats published in 2007.

In his latest study, for example, he found that a type of adenocarcinoma -- a highly malignant tumor and the main cause of death of breast-cancer patients, as well as of animals with mammary cancer -- was evident in 81 percent of tumors in the control animals. However, it developed in only 57 percent, 50 percent and 23 percent of the rats fed low, middle and high doses of apple extracts (the equivalent of one, three and six apples a day in humans), respectively, during the 24-week study.

Fruits and vegetables are the ticket. Eat more of them and less of everything else.

By Randall Parker    2009 February 19 12:26 AM   Entry Permalink | Comments (3)
2009 February 04 Wednesday
Beans Cut Cancer Mammary Risk In Lab Rats

Lab rats are chewing on beans to cut their mammary cancer risks.

Madison, WI, February 2, 2009 - As the world seeks new ways to prevent and treat chronic diseases such as diabetes, heart disease and cancer, more research continues to be conducted on the benefits of certain foods in reducing people’s risk of contracting these ailments. Legumes in particular are often cited as being high in antioxidants, which have the property of being able to fight off free radical cells within the body, reducing the risk of cancer and other chronic diseases. A recent study further investigated these connections, as researchers focused on the benefits of one type of legume, dry beans, in reducing the risk of mammary cancer.

To address whether dry bean consumption is associated with a reduction in mammary cancer, scientists at Colorado State University studied the anticancer activity of six market classes of bean including; small red, great northern, navy, black, dark red and white kidney bean in the diet of laboratory animals. They also evaluated whether the level of antioxidants or seed coat pigments in the bean were related to mammary cancer. The study was funded by a grant from the Beans for Health Alliance, and the Colorado Agricultural Experiment Station with assistance from Archer Daniels Midland Co. and Bush Brothers Inc. Results from the study were published in the January-February 2009 issue of the journal Crop Science.

More darkly colored beans score higher in various measures of antioxidant activity.

Cooked dry bean powder from the six market classes and a control group without beans in the diet were fed to laboratory rats in a standard preclinical model for breast cancer. The dry bean powders were also evaluated for antioxidant capacity, phenolic and flavonoid content; all factors thought to be associated with anticancer activity. Chemical analysis of the beans revealed that total phenolic and flavonoid content varied widely among market classes and the differences were strongly associated with seed coat color; where colored beans had ten times or greater phenolic and flavonoid content compared to white beans. Antioxidant capacity of the beans also varied widely among dry bean market classes and were highly related to seed coat color, where colored beans had approximately two to three times greater antioxidant capacity than white beans.

But the lighter beans were just as effective at cutting cancer incidence as the darker beans that contain more antioxidants. Go figure.

Dry bean consumption from every market class reduced cancer incidence (number of animals with one tumor) and tumor number per animal compared to the control group. Cancer incidence was reduced from 95% in the control group to 67% in animals fed beans. The average number of malignant tumors was also reduced from 3.2 in the control group to 1.4 tumors per animal in the group fed bean. No associations were observed between phenolic content, flavonoid content and antioxidant capacity with cancer among the bean market classes. These results clearly suggest that the anticancer activity in dry bean is not associated with seed color or antioxidant capacity.

So what about beans delivered the anti-cancer benefit? Does a fiber in the beans cut cancer risks somehow?

For added anti-cancer protection take vitamin D with your beans.

Calcitrol, the active form of vitamin D, has been found to induce a tumor suppressing protein that can inhibit the growth of breast cancer cells, according to a study by researcher Sylvia Chistakos, Ph.D., of the UMDNJ-New Jersey Medical School.

Chistakos, a professor of biochemistry, has published extensively on the multiple roles of vitamin D, including inhibition of the growth of malignant cells found in breast cancer. Her current findings on the vitamin D induced protein that inhibits breast cancer growth are published in a recent issue of The Journal of Biological Chemistry.

Previous research had determined that increased serum levels of vitamin D are associated with an improved diagnosis in patients with breast cancer. Prior to the current study, little was known about the factors that determine the effect of calcitrol on inhibiting breast cancer growth, she said.

The vitamin D might make you stronger too. Though maybe people who get outside more get more exercise and get exposed to more sun which raises blood vitamin D levels.

By Randall Parker    2009 February 04 11:45 PM   Entry Permalink | Comments (5)
Soy Cuts Colorectal Cancer Risk

Protect your colon with soy.

A new study published in the American Journal of Clinical Nutrition explores how soyfood consumption may lower the risk of colorectal cancer, or cancer of the colon or rectum, in postmenopausal women. According to the National Cancer Institute, an estimated 71,560 American women were diagnosed with the fourth most common cancer in 2008.

Vanderbilt University School of Medicine researchers found that women who consumed at least 10 grams of soy protein daily were one-third less likely to develop colorectal cancer in comparison to women who consumed little soy. This is the amount of soy protein available in approximately one serving of tofu (1/2 cup), roasted soy nuts (1/4 cup), edamame (1/2 cup) or soy breakfast patties (2 patties).

The study observed soy intake in 68,412 women between the ages of 40 and 70, all free of cancer and diabetes prior to the initial screening. Researchers identified 321 colorectal cancer cases after participants were monitored for an average of 6.4 years. After adjusting for confounding factors, total soyfood intake was inversely associated with colorectal cancer risk among postmenopausal women.

Note that this study does not address whether soy will cut colon cancer risks in men or younger women.

I wonder if the scientists adjusted for meat consumption. People who eat soy burgers are probably less likely to eat hamburgers.

By Randall Parker    2009 February 04 11:36 PM   Entry Permalink | Comments (1)
2009 January 02 Friday
Vitamins C, E, Beta Carotene Fail To Cut Cancer Risk

Simple antioxidant pills for cancer risk reduction aren't looking like a good bet.

Women who took beta carotene or vitamin C or E or a combination of the supplements had a similar risk of cancer as women who did not take the supplements, according to data from a randomized controlled trial in the December 30 online issue of the Journal of the National Cancer Institute.

People who eat lots of fruits and vegetables get less cancer. But other people do not like to eat lots of fruits and vegetables. They'd rather chow down on a Big Mac, a Whopper, or maybe some Twinkies with a chocolate milk shake. Still, veggies and fruits really are the ticket.

Epidemiological studies have suggested that people whose diets are high in fruits and vegetables, and thus antioxidants, may have a lower risk of cancer. Results from randomized trials that address the issue, however, have been inconsistent and have rarely supported that observation.

The problem is knowing what in the foods cut cancer risks. Could be fiber. Could be non-vitamin antioxidants such as polyphenols. Could be minerals like magnesium. Or maybe the veggies with lower glycemic index just reduce the sugar surge after meals and therefore reduce the surge in insulin and other hormones that can stimulate cells to become cancerous. Probably the answer is multiple factors in fruits and vegetables mean it is hard to find a shortcut.

In the current study, Jennifer Lin, Ph.D., of the Brigham and Women's Hospital and Harvard Medical School in Boston, and colleagues tested the impact of antioxidant supplements on cancer incidence in a randomized controlled trial. A total of 7,627 women who were at high risk of cardiovascular disease were randomly assigned to take vitamin C, vitamin E, or beta-carotene.

With an average of 9.4 years of follow-up time, there was no statistically significant benefit from antioxidant use compared with placebo in terms of disease risk or mortality due to cancer. Overall, 624 women developed cancer and 176 died from cancer during the follow-up time. Compared with placebo, the relative risk of a new cancer diagnosis was 1.11 for women who took vitamin C, 0.93 for women who took vitamin E, and 1.00 for women who took beta carotene. None of these relative risks was statistically significantly different from 1.

Eat good food. Some day scientists will come up with a way to make The Six Dollar Burger and hot dogs as beneficial as cabbage, eggplant, and arugula. But that day hasn't come yet.

By Randall Parker    2009 January 02 11:20 PM   Entry Permalink | Comments (5)
Inorganic Phosphates Boost Lung Cancer?

Think processed foods are bad for you? Not sure why exactly? One possibility: inorganic phosphates in food might boost the growth of lung cancer.

New research in an animal model suggests that a diet high in inorganic phosphates, which are found in a variety of processed foods including meats, cheeses, beverages, and bakery products, might speed growth of lung cancer tumors and may even contribute to the development of those tumors in individuals predisposed to the disease.

The study also suggests that dietary regulation of inorganic phosphates may play an important role in lung cancer treatment. The research, using a mouse model, was conducted by Myung-Haing Cho, D.V.M., Ph.D., and his colleagues at Seoul National University, appears in the first issue for January of the American Journal of Respiratory and Critical Care Medicine, published by the American Thoracic Society.

"Our study indicates that increased intake of inorganic phosphates strongly stimulates lung cancer development in mice, and suggests that dietary regulation of inorganic phosphates may be critical for lung cancer treatment as well as prevention," said Dr. Cho.

Of course, if you are eating a diet high in vegetables and fruits and low in processed foods you do not need to know why exactly the processed foods are bad for you. Whether this study has identified a real reason to avoid processed foods or not we already know that drinking colas or other sodas isn't good for us and neither is eating processed cheese spread.

By Randall Parker    2009 January 02 09:04 PM   Entry Permalink | Comments (2)
2008 December 02 Tuesday
Choline During Pregnancy Slows Rat Breast Cancer

At least if you are a rat (and some people are) if your mom consumed a lot of choline during pregnancy she probably slowed the development of eventual breast cancer.

A stunning discovery based on epigenetics (the inheritance of propensities acquired in the womb) reveals that consuming choline—a nutrient found in eggs and other foods—during pregnancy may significantly affect breast cancer outcomes for a mother's offspring. This finding by a team of biologists at Boston University is the first to link choline consumption during pregnancy to breast cancer. It also is the first to identify possible choline-related genetic changes that affect breast cancer survival rates.

"We've known for a long time that some agents taken by pregnant women, such as diethylstibesterol, have adverse consequences for their daughters," said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal. "But there's an upside. The emerging science of epigenetics has yielded a breakthrough. For the first time, we've learned that we might be able to prevent breast cancer as early as a mother's pregnancy."

The researchers made the discovery in rats by studying females whose mothers were fed varying amounts of choline during pregnancy. Different groups of pregnant rats received diets containing standard amounts of choline, no choline at all, or extra choline. Then the researchers treated the female offspring with a chemical that causes cancer of the mammary gland (breast cancer). Although animals in all groups developed mammary cancer, the daughters of mothers that had received extra choline during pregnancy had slow growing tumors while daughters of mothers that had no choline during pregnancy had fast growing tumors.

So if you see a pregnant rat feed it some hard boiled eggs. Think of the children.

Seriously though, suppose we eventually get sound advice for what dietary factors during pregnancy will influence eventual cancer risk. Will this do any good? I don't think so. If we know by 2015 what is the best cancer-minimizing diet during pregnancy the result will be to protect against diseases that won't develop until 2045 and mostly much later. By 2045 I will be very surprised if cancer isn't totally and easily cured.

What would be more useful to know: Does choline consumption decrease breast cancer risk if the choline consumption is started later?

By Randall Parker    2008 December 02 11:31 PM   Entry Permalink | Comments (0)
2008 November 21 Friday
Raw Cruciferous Vegetables Cut Lung Cancer Risk

Raw cruciferous vegetables cut the risk of lung cancer among smokers.

WASHINGTON, D.C. - The cancer preventive properties of broccoli and other cruciferous vegetables appear to work specifically in smokers, according to data presented at the American Association for Cancer Research's Seventh Annual International Conference on Frontiers in Cancer Prevention Research.

Cruciferous vegetables have been shown to be protective in numerous studies, but this is the first comprehensive study that showed a protective benefit in smokers, specifically in former smokers, according to lead author Li Tang, Ph.D., a post-doctoral fellow at Roswell Park Cancer Institute.

If you can't stop smoking at least eat lots of cabbage and broccoli.

Among smokers, the protective effect of cruciferous vegetable intake ranged from a 20 percent reduction in risk to a 55 percent reduction in risk depending on the type of vegetable consumed and the duration and intensity of smoking.

For example, among current smokers, only the consumption of raw cruciferous vegetables was associated with risk reduction of lung cancer. No significant results were found for consumption of vegetables in general and fruits.

Eating vegetables is one of the few things you can do that will slow the aging process and make you feel better. If you do not like vegetables wolf them down quickly at the beginning of a meal just to get them out of the way.

By Randall Parker    2008 November 21 12:02 AM   Entry Permalink | Comments (9)
2008 November 19 Wednesday
Calcium And Magnesium For Lower Colorectal Cancer Risk

Higher calcium does not lower risk of colorectal cancer adenoma without lots of magnesium along with it.

High magnesium intake has been associated with low risk of colorectal cancer. Americans have similar average magnesium intake as East Asian populations. If that were all that were involved, observers might expect both groups to have similar risk for colorectal cancer.

However, the United States has seen a much higher colorectal cancer incidence rate than East Asian populations. Furthermore, when East Asians immigrated to the United States, their incidence rates for colorectal cancer increased. This led researchers at Vanderbilt University to suspect there was something else at work.

Calcium supplementation has been shown to inhibit colorectal carcinogenesis although high calcium may simultaneously be preventing the body from absorbing magnesium. United States patients have a higher calcium intake and higher colorectal cancer incidence. "If calcium levels were involved alone, you'd expect the opposite direction. There may be something about these two factors combined – the ratio of one to the other – that might be at play", said Qi Dai, M.D., Ph.D., assistant professor of medicine at Vanderbilt University.

Dai and colleagues examined this hypothesis in a large clinical trial and found indeed that supplementation of calcium only reduced the risk of adenoma recurrence if the ratio of calcium to magnesium was low and remained low during treatment. "The risk of colorectal cancer adenoma recurrence was reduced by 32 percent among those with baseline calcium to magnesium ratio below the median in comparison to no reduction for those above the median," said Qi.

Parenthetically, magnesium is one of the few supplements I take and I never take calcium without magnesium. The magnesium delivers other benefits including lowered risk of the metabolic syndrome and type 2 diabetes.

By Randall Parker    2008 November 19 10:58 PM   Entry Permalink | Comments (0)
2008 November 14 Friday
Red Meat Molecule Boosts Human Cancer Risk?

Why do people who eat a lot of meat and milk products get cancer more often? A glycan (a type of polysaccharide) molecule present in red meat and milk products might elicit an immune response that stimulates tumor growth.

Researchers at the University of California, San Diego School of Medicine, led by Ajit Varki, M.D., have shown a new mechanism for how human consumption of red meat and milk products could contribute to the increased risk of cancerous tumors. Their findings, which suggest that inflammation resulting from a molecule introduced through consumption of these foods could promote tumor growth, are published online this week in advance of print publication in the Proceedings of the National Academy of Sciences (PNAS).

Varki, UC San Diego School of Medicine distinguished professor of medicine and cellular and molecular medicine, and co-director of the UCSD Glycobiology Research and Training Center, and colleagues studied a non-human cellular molecule called N-glycolylneuraminic acid (Neu5Gc). Neu5Gc is a type of glycan, or sugar molecule, that humans don't naturally produce, but that can be incorporated into human tissues as a result of eating red meat. The body then develops anti-Neu5Gc antibodies – an immune response that could potentially lead to chronic inflammation, as first suggested in a 2003 PNAS paper by Varki.

In mice the combination of the Neu5Gc glycan and immune antibodies against Neu5Gc caused tumors to grow quicker. Drugs that reduce inflammation might cut cancer risk by suppressing an immune response to Neu5Gc.

Using specially bred mouse models that lacked the Neu5Gc molecule – mimicking humans before the molecule is absorbed into the body through ingesting red meat – the researchers induced tumors containing Neu5Gc, and then administered anti-Neu5Gc antibodies to half of the mice. In mice that were given antibodies inflammation was induced, and the tumors grew faster. In the control mice that were not treated with antibodies, the tumors were less aggressive

Others have previously shown that humans who take non-steroidal anti-inflammatory drugs (commonly known as NSAIDs) have a reduced risk of cancer. Therefore, the mice with cancerous tumors facilitated by anti-Neu5Gc antibodies were treated with an NSAID. In these animals, the anti-inflammatory treatment blocked the effect of the Neu5Gc antibodies and the tumors were reduced in size.

"Taken together, our data indicate that chronic inflammation results from interaction of Neu5Gc accumulated in our bodies from eating red meat with the antibodies that circulate as an immune response to this non-human molecule – and this may contribute to cancer risk," said Varki.

This result is important because it suggests you probably can't neutralize all the cancer risk associated with greater meat and milk consumption. As long as you are eating sources of Neu5Gc you are boosting your risk of cancer.

Though not all studies find a strong link between cancer and red meat consumption. Another recent study found that the risk small intestine cancer seemed to be boosted by saturated fat consumption and not by red meat. Of course a lot of red meat is high in saturated fat. This result holds out the hope that lean red meat might not boost your cancer risk.

Cross and other researchers from the National Cancer Institute used food frequency questionnaires to track food intake in a half million men and women enrolled in the NIH -AARP Diet and Health study over an eight-year period. Through state cancer registries and national death indexes researchers noted the development of 60 adenocarcinomas and 80 carcinoid tumors of the small intestine.

While findings showed no clear connection between red and processed meat and these tumors, they suggested a noticeably elevated risk for carcinoid tumors in the small intestine in association with saturated fat intake.

If you eat more fruits and vegetables they will displace less healthy foods from your diet. Add omega 3 fatty acids since they probably counteract the harmful effects of too much omega 6 fats from red meat and dairy.

By Randall Parker    2008 November 14 12:50 AM   Entry Permalink | Comments (3)
2008 October 31 Friday
Might Resveratrol Cut Hereditary Breast Cancer Risk?

Resveratrol (which is sold over-the-counter at least in some countries) might work against breast cancer that is caused by hereditary mutation of the BRCA1 gene.

Dr. Deng and colleagues were interested in investigating the relationship among BRCA1, SIRT1 and Survivin. SIRT1 is a protein and histone deacetylase involved in numerous critical cell processes including metabolism, DNA repair and programmed cell death, known as apoptosis. Although SIRT1 has been implicated in tumorigenesis, no concrete role in cancer initiation or progression has been identified. Survivin is an apoptosis inhibitor that is dramatically elevated in many types of tumors. Research has suggested that Survivin may serve to maintain the tumor and promote growth.

The researchers found that BRCA1 functioned as a tumor suppressor by maintaining SIRT1 expression, which in turn inhibited Survivin expression. When BRCA1 was not functioning properly, SIRT levels decreased and Survivin levels increased, allowing BRCA1-deficient cells to overcome apoptosis and undergo malignant transformation.

They went on to show that the compound resveratrol strongly inhibited BRCA1-mutant tumor growth in cultured cells and animal models. Resveratrol is an important constituent of traditional Japanese and Chinese medicine that has recently been shown to inhibit some types of cancer by inducing apoptosis with very little associated toxicity. In the current paper, resveratrol enhanced SIRT1 activity, this leading to reduced Survivin expression and subsequent apoptosis of BRCA1 deficient cancer cells.

These findings identify SIRT1 and Survivin as downstream mediators of BRCA1-regulated tumor suppression and identify resveratrol as a potent inhibitor of BRCA1-mutant cancer cells. "Resveratrol may serve as an excellent compound for targeted therapy for BRCA1 associated breast cancers," says Dr. Deng.

If resveratrol really works in the way described there is a substantial chance that resveratrol might decrease the odds of getting breast cancer in the first place - especially among women who have the BRCA1 mutation that increases the odds of getting breast cancer. Resveratrol appears to substitute for properly formed BRCA1 and enhance SIRT1 which lowers the expression of Survivin. Survivin helps keep cells alive. So less Survivin causes more cancer cells to commit suicide.

Here is the abstract.

Germline mutations of BRCA1 predispose women to breast and ovarian cancers. However, the downstream mediators of BRCA1 function in tumor suppression remain elusive. We found that human BRCA1-associated breast cancers have lower levels of SIRT1 than their normal controls. We further demonstrated that mammary tumors from Brca1 mutant mice have low levels of Sirt1 and high levels of Survivin, which is reversed by induced expression of Brca1. BRCA1 binds to the SIRT1 promoter and increases SIRT1 expression, which in turn inhibits Survivin by changing the epigenetic modification of histone H3. Absence of SIRT1 blocks the regulation of Survivin by BRCA1. Furthermore, we demonstrated that activation of Sirt1 and inhibition of Survivin expression by resveratrol elicit a more profound inhibitory effect on Brca1 mutant cancer cells than on Brca1-wild-type cancer cells both in vitro and in vivo. These findings suggest that resveratrol treatment serves as an excellent strategy for targeted therapy for BRCA1-associated breast cancer.

I periodically mull over the possibility of taking resveratrol for its various reported benefits. Still haven't crossed over to taking it yet. I expect I'll take it when I get older and my risk of cancer goes up.

By Randall Parker    2008 October 31 04:42 AM   Entry Permalink | Comments (2)
2008 October 29 Wednesday
Vitamin E And Selenium Fail To Cut Prostate Cancer Risk

A big trial fails to find confirmation for earlier reports of a reduced prostate cancer risk from selenium and vitamin E.

Initial, independent review of study data from the Selenium and Vitamin E Cancer Prevention Trial (SELECT), funded by the National Cancer Institute (NCI) and other institutes that comprise the National Institutes of Health shows that selenium and vitamin E supplements, taken either alone or together, did not prevent prostate cancer. The data also showed two concerning trends: a small but not statistically significant increase in the number of prostate cancer cases among the over 35,000 men age 50 and older in the trial taking only vitamin E and a small, but not statistically significant increase in the number of cases of adult onset diabetes in men taking only selenium. Because this is an early analysis of the data from the study, neither of these findings proves an increased risk from the supplements and both may be due to chance.

Other dietary changes to cut prostate cancer risk look more promising. Eat more fruits and vegetables and omega 3 fatty acids. Eat less saturated fats from meat.

By Randall Parker    2008 October 29 07:52 PM   Entry Permalink | Comments (1)
2008 October 14 Tuesday
Pectin Binds To Protein Involved In Cancer Progression

Pectin, a carbohydrate found in many fruits and vegetables, might contribute to the anti-cancer effect of fruits and vegetables

Scientists have found a new possible explanation for why people who eat more fruit and vegetables may gain protection against the spread of cancers.

They have shown that a fragment released from pectin, found in all fruits and vegetables, binds to and is believed to inhibit galectin 3 (Gal3), a protein that plays a role in all stages of cancer progression.

"Most claims for the anticancer effects of foods are based on population studies," says Professor Vic Morris from the Institute of Food Research. "For this research we tested a molecular mechanism and showed that it is viable."

Population studies such as EPIC, the European Prospective Investigation of Cancer, identified a strong link between eating lots of fibre and a lower risk of cancers of the gastrointestinal tract. But exactly how fibre exerts a protective effect is unknown.

Pectin is better known for its jam-setting qualities and as being a component of dietary fibre. The present study supports a more exciting and subtle role.

Some readers ask me to write up the complete definitive scientific diet. I keep telling them that they already know what they ought to do but that they do not find the best diet appealing. Very few eat 10 servings of fruits and vegetables per day. Well, that's what you need to do. Just doing that will displace lots of junk out of your diet. But vegetables aren't much fun. Well, there's still fruits.

By Randall Parker    2008 October 14 12:21 AM   Entry Permalink | Comments (1)
2008 August 29 Friday
Anti-Cancer Effect Of Black Raspberries At Genetic Level

How do vegetables and fruits reduce our risk of cancer? While this latest report doesn't show every step on the mechanism of effect part of the effect can be measured by looking at levels of gene expression. Black raspberries partially restore gene expression to normal levels in rats after exposure to a carcinogen (a cancer causing compound).

COLUMBUS, Ohio – New research strongly suggests that a mix of preventative agents, such as those found in concentrated black raspberries, may more effectively inhibit cancer development than single agents aimed at shutting down a particular gene.

Researchers at the Ohio State University Comprehensive Cancer Center examined the effect of freeze-dried black raspberries on genes altered by a chemical carcinogen in an animal model of esophageal cancer.

After exposure to a carcinogen blackberry powder restored less than a fifth of the affected genes to normal level.

The carcinogen affected the activity of some 2,200 genes in the animals’ esophagus in only one week, but 460 of those genes were restored to normal activity in animals that consumed freeze-dried black raspberry powder as part of their diet during the exposure.

Better not get exposed to carcinogens in the first place. But a lot of the mutations that lead to cancer happen even in the absence of environmental carcinogens. They just happen at a faster rate when carcinogens are present.

By Randall Parker    2008 August 29 07:04 AM   Entry Permalink | Comments (5)
2008 August 05 Tuesday
Injected Vitamin C Kills Cancer

By bypassing regulatory systems that control internal vitamin C levels scientists were able boost vitamin C concentrations so high that it killed cancer cells.

High-dose injections of vitamin C, also known as ascorbate or ascorbic acid, reduced tumor weight and growth rate by about 50 percent in mouse models of brain, ovarian, and pancreatic cancers, researchers from the National Institutes of Health (NIH) report in the August 5, 2008, issue of the Proceedings of the National Academy of Sciences. The researchers traced ascorbate's anti-cancer effect to the formation of hydrogen peroxide in the extracellular fluid surrounding the tumors. Normal cells were unaffected.

Natural physiologic controls precisely regulate the amount of ascorbate absorbed by the body when it is taken orally. "When you eat foods containing more than 200 milligrams of vitamin C a day--for example, 2 oranges and a serving of broccoli--your body prevents blood levels of ascorbate from exceeding a narrow range," says Mark Levine, M.D., the study's lead author and chief of the Molecular and Clinical Nutrition Section of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the NIH. To bypass these normal controls, NIH scientists injected ascorbate into the veins or abdominal cavities of rodents with aggressive brain, ovarian, and pancreatic tumors. By doing so, they were able to deliver high doses of ascorbate, up to 4 grams per kilogram of body weight daily. "At these high injected doses, we hoped to see drug-like activity that might be useful in cancer treatment," said Levine.

Keep in mind that cutting tumor size by 50% does not cure cancer. The remaining cells can bounce back and still kill you. But maybe combined with other treatments vitamin C can help fight cancer.

By Randall Parker    2008 August 05 12:13 AM   Entry Permalink | Comments (7)
2008 June 19 Thursday
Weight Loss Surgery Cuts Cancer Risk

For those who are morbidly obese bariatric surgery causes a large cut in cancer risk.

Montreal, 19 June 2008 – Successful bariatric surgery allows morbidly obese patients to lose up to 70 percent of their excess weight and to maintain weight loss. The latest study by Dr. Nicolas Christou of the McGill University Health Centre (MUHC) and McGill University shows that this surgery also decreases the risk of developing cancer by up to 80 percent. Dr. Christou presented his preliminary results yesterday at the 25th Annual Meeting of the American Society for Metabolic & Bariatric Surgery.

The researchers compared 1,035 morbidly obese patients who underwent bariatric surgery at the MUHC between 1986 and 2002 with 5,746 patients with the same weight profile who did not undergo the operation. The number of cancer diagnoses in first group was 85 percent lower for breast cancer and 70 percent lower for colon and pancreatic cancers, and was also distinctly lower for several other types of cancer.

"The relationship between obesity and many forms of cancer is well established," said Dr. Christou. "This is one of the first studies to suggest that bariatric surgery might prevent the risk of cancer for a significant percentage of morbidly obese people."

By Randall Parker    2008 June 19 10:36 PM   Entry Permalink | Comments (1)
2008 May 29 Thursday
Tomato Powder Strongest Against Prostate Cancer

In a study that throws doubt on lycopene as the source of suspected protective effects of tomatoes against prostate cancer a compound found in rehydrated tomato powder seems to deliver the biggest protective effect against prostate cancer.

COLUMBIA, Mo. – New cancer research from the University of Missouri suggests that eating a certain form of tomato product could be the key to unlocking the prostate cancer-fighting potential of the tomato. The positive effect of tomato products has been suggested in many studies, but, until now, researchers did not know exactly what caused this effect.

“It appears that the greatest protective effect from tomatoes comes from rehydrating tomato powder into tomato paste,” said Valeri Mossine, research assistant professor of biochemistry in the College of Agriculture, Food and Natural Resources. “Processing of many edible plants through heating, grinding, mixing or drying dramatically increases their nutritional value and cancer-fighting potential.”

Mossine and his colleagues found that FruHis – an organic carbohydrate present in dehydrated tomato products – exerts a strong protective effect against prostate cancer. Rats, injected with prostate cancer-causing chemicals, were divided into groups and fed different diets. The group fed a diet of tomato paste plus additional FruHis demonstrated the longest survival rate. Only 10 percent in that group had developed prostate tumors. Sixty percent in the control group had tumors; 30 percent of the group fed tomato powder had tumors; and 25 percent of the group fed tomato paste alone had prostate tumors.

“Before this study, researchers attributed the protective effect of tomatoes to ascorbic acid, carotenoids or phenolic compounds. FruHis may represent a novel type of potential dietary antioxidant,” Mossine said. “Our ongoing research now focuses on unraveling the mechanisms behind why this has a beneficial effect. This knowledge may lead to other avenues of research and drug development for prostate and other cancers. Results of this study certainly warrant clinical trials.”

Tomato paste still did pretty well and even did better than tomato powder that didn't have the extra FruHis added. So keep eating tomato paste.

By Randall Parker    2008 May 29 11:07 PM   Entry Permalink | Comments (8)
2008 May 20 Tuesday
Vitamin D Up-Regulates Protective Enzyme In Prostate Cells

Vitamin D might reduce the risk of prostate cancer by up-regulating an enzyme that breaks down reactive oxygen species (which would otherwise damage cells and perhaps lead to cancer).

By inducing a specific gene to increase expression of a key enzyme, vitamin D protects healthy prostate cells from the damage and injuries that can lead to cancer, University of Rochester Medical Center researchers report.

“Many epidemiological studies have suggested the beneficial properties of vitamin D,” said Yi-Fen Lee, associate professor of urology at the Medical Center who led the research. “Our findings reflect what we see in those studies and demonstrate that vitamin D not only can be used as a therapy for prostate cancer, it can prevent prostate cancer from happening.”

Vitamin D turns up the activity of an enzyme that breaks down reactive oxygen species (ROS or free radicals).

Lee found that vitamin D links with a gene known as G6PD, increasing its activity and the production of an enzyme called glucose-6-phosphate dehydrogenase. Increased activity of the enzyme clears cells of ROS, the molecules that can damage and injure cells.

“If you reduce DNA damage, you reduce the risk of cancer or aging,” Lee said. “Our study adds one more beneficial effect of taking a vitamin D supplement. Taking a supplement is especially important for senior citizens and others who might have less circulation of vitamin D, and for people who live and work areas where there is less sunshine.”

Vitamin D deficiency correlates with a much higher rate of breast cancer metastasis.

Women who had a vitamin D deficiency when they were diagnosed with breast cancer were 94% more likely to have their cancer metastasize and 73% more likely to die within 10 years, Canadian researchers reported Thursday.

The team also found that only 24% of the women in its study had what are normally considered adequate levels of vitamin D at the time of the diagnosis.

The study represents "the first time that vitamin D has been linked to breast cancer progression," said Dr. Pamela Goodwin of Mount Sinai Hospital in Toronto, who led the study.

Most women diagnosed with breast cancer are deficient in vitamin D.

Surprisingly, the researchers also found that only 24 percent of the patients had adequate levels of vitamin D when they were diagnosed.

"This study found that vitamin D deficiency is very common among women with breast cancer, and it suggests that vitamin D deficiency is linked to poorer outcomes in these women," Dr. Nancy Davidson, director of the breast cancer program at the Johns Hopkins Kimmel Cancer Center, said during a May 6 press conference. Davidson is president of the American Society of Clinical Oncology (ASCO).

Vitamin D deficiency is very common because we spend so much time indoors and few eat a lot of food high in vitamin D.

By Randall Parker    2008 May 20 10:24 PM   Entry Permalink | Comments (1)
2008 April 20 Sunday
Vitamin D Cuts Breast Cancer Risk?

If you aren't getting enough vitamin D you might be increasing your cancer risk.

A connection between vitamin D level and the risk of developing breast cancer has been implicated for a long time, but its clinical relevance had not yet been proven. Sascha Abbas and colleagues from the working group headed by Dr. Jenny Chang-Claude at the German Cancer Research Center (Deutsches Krebsforschungszentrum, DKFZ), collaborating with researchers of the University Hospitals in Hamburg-Eppendorf, have now obtained clear results: While previous studies had concentrated chiefly on nutritional vitamin D, the researchers have now investigated the complete vitamin D status. To this end, they studied 25-hydroxyvitamin D (25(OH)D) as a marker for both endogenous vitamin D and vitamin D from food intake.

The result of the study involving 1,394 breast cancer patients and an equal number of healthy women after menopause was surprisingly clear: Women with a very low blood level of 25(OH)D have a considerably increased breast cancer risk. The effect was found to be strongest in women who were not taking hormones for relief of menopausal symptoms. However, the authors note that, in this retrospective study, diagnosis-related factors such as chemotherapy or lack of sunlight after prolonged hospital stays might have contributed to low vitamin levels of breast cancer patients.

A prospective study that tracks the blood vitamin D level of lots of women for years would be more definitive. But such studies are much more expensive. Another way to get at the question: a study that checks vitamin D levels at the time of mammograms for women with suspicious lumps. The blood samples could be held and not tested for vitamin D until mammogram results are known. That would reduce the number of vitamin D tests done on women without breast cancer.

By Randall Parker    2008 April 20 10:15 AM   Entry Permalink | Comments (1)
2008 February 24 Sunday
Starch Rich Foods Risks For Breast And Ovarian Cancers

Animal products are associated with lowered risks of breast and ovarian cancers. Eat diets richer in vitamins, fiber, unsaturated fats, and animal fats.

We identified 4 major dietary patterns named Animal products, Vitamins and fiber, Unsaturated fats and Starch-rich. The animal products pattern and the unsaturated fats pattern were inversely associated with breast cancer (OR = 0.74, 95% CI: 0.61-0.91 and OR = 0.83, 95% CI: 0.68-1.00, respectively, for the highest consumption quartile), whereas the starch-rich pattern was directly associated with it (OR = 1.34, 95% CI: 1.10-1.65). The vitamins and fiber pattern was inversely associated with ovarian cancer (OR = 0.77, 95% CI: 0.61-0.98), whereas the starch-rich pattern was directly associated with it (OR = 1.85, 95% CI: 1.37-2.48). In conclusion, the starch-rich pattern is potentially an unfavorable indicator of risk for both breast and ovarian cancers, while the animal products and the vitamins and fiber patterns may be associated with a reduced risk of breast and ovarian cancers, respectively.

Yes kids, glucose can do more damage to your body than protein. That could be the result of higher blood levels of insulin and insulin-like growth factor. My guess is that a lower glycemic index diet might not increase cancer risks as much as a higher glycemic index diet with the same amount of carbohydrates.

Previous studies have produced different results. We can't be certain this latest study is correct.

High alcohol intake has been consistently linked to breast cancer risk, but when it comes to other facets of the diet, studies have yielded conflicting results, according to the researchers on the current work, led by Dr. Valeria Edefonti of the University of Milan.

Another study just out in the American Journal of Epidemiology finds that men who eat a high fat diet are at greater risk of benign prostate hyperplasia (BPH).

The researchers found that a high-fat diet increased the risk of benign enlargement of the prostate by 31 percent, and that daily consumption of red meat increased the risk by 38 percent.

The study also found that eating four or more servings of vegetables daily was associated with a 32-percent reduction in risk, consuming high amounts of lean protein (about 20 percent of daily calorie intake) was associated with a 15-percent risk reduction, and that regular, moderate alcohol consumption (no more than two drinks a day) was associated with a 38-percent decline in BPH risk.

Note that for women that alcohol consumption will probably up your breast cancer risk. Also, other studies find increased risk of colon cancer from eating processed meats. So avoid the hot dogs and salami.

Proteins from lean sources are best for men.

Red meat increased the likelihood of BPH, but only in men who ate it every day. Men who ate the most fat were 31% more likely to develop BPH, while the highest consumers of protein actually cut their risk by 15%.

The protein finding "doesn't mean go out and eat lean meat, it means go out and find lean sources of protein, which can be quite diverse," Kristal told Reuters Health, pointing to beans and vegetable proteins as two possibilities.

I wonder whether the BPH risk comes from all sources of fats or just particular kinds of fats.

While the net effects of some types of foods might seem controversial note that the benefits of vegetables consumption seem pretty clear. Vegetables will cut the risks of many types of cancer as well as other diseases of old age.

By Randall Parker    2008 February 24 12:15 AM   Entry Permalink | Comments (0)
2008 January 30 Wednesday
Zinc Lowers Prostate Cancer Risk From Cadmium?

Zinc seems to cancel out the cancer risk of cadmium.

Cadmium exposure is a known risk factor for prostate cancer, and a new University of Rochester study suggests that zinc may offer protection against cadmium.

In an article published in the February 2008 journal, The Prostate, epidemiologist Edwin van Wijngaarden, Ph.D., reports that PSA levels were 22 percent higher among American men who had zinc levels below the median (less than 12.67 mg/daily) and cadmium levels above the median. (PSA is a protein produced by the cells of the prostate gland. The higher a man’s PSA level, the more likely cancer is present.)

In contrast, among men with a greater than median zinc intake, little evidence of an association between cadmium and PSA was found.

This result seems especially important for cigarette smokers who breathe in cadmium on a daily basis.

The result is plausible because there is a biological mechanism by which zinc provides protection.

The way zinc and cadmium interact within human organs is significant and provides interesting leads for study, van Wijngaarden said. Zinc stimulates production of a protein that binds cadmium thereby taking it out of circulation and reducing its toxic effects.

Oysters, beef, turkey, and chickpeas are all good sources of zinc. Also, many nuts and seeds are good zinc sources.

But you might not have to worry about high testosterone as a cancer risk.

Sex hormones circulating in the blood do not appear to be associated with prostate cancer risk, according to data from 18 prior studies. The analysis will be published online January 29 in the Journal of the National Cancer Institute.

Having high levels of male sex hormones, known as androgens, has long been hypothesized as a risk factor for prostate cancer. Nearly two dozen prospective studies have examined the relationship between circulating sex hormones and prostate cancer risk, but the results have been inconsistent.

Andrew Roddam, D.Phil., of the University of Oxford in England and colleagues at the Endogenous Hormones and Prostate Cancer Collaborative Group collected the original data from 18 studies and analyzed it to determine the relationship between blood levels of sex hormones and prostate cancer. The pooled data included 3,886 men with prostate cancer and 6,438 controls.

The researchers found no association between prostate cancer risk and blood levels of different forms of testosterone or estrogen.

By Randall Parker    2008 January 30 10:05 PM   Entry Permalink | Comments (2)
2007 November 23 Friday
Grapes Might Reduce Colon Cancer Risk

A moderate dose of grapes per day seems to suppress a genetic pathway involved in colon cancer development.

Led by Dr. Randall Holcombe, director of clinical research at the Chao Family Comprehensive Cancer Center at UC Irvine, the study followed up on previous in vitro studies showing that resveratrol, a nutritional supplement derived from grape extract, blocks a cellular signaling pathway known as the Wnt pathway. The Wnt pathway has been linked to more than 85 percent of sporadic colon cancers, which is the most common form of colon cancer.

The UC Irvine researchers conducted their study with colon cancer patients. One group was given 20 milligrams daily of resveratrol as a pill; another drank 120 grams daily of grape powder mixed in water; and a third drank 80 grams daily of grape powder.

While the supplements did not have an impact on existing tumors, biopsied colon tissue showed that Wnt signaling in the patients taking 80 grams of grape powder was significantly reduced. Similar changes were not seen in patients taking the higher dose of grape powder or the resveratrol pills.

So excess is not always best and the whole food has advantages over the supplement pill.

Up for a pound of grapes every day?

Eighty grams of grape powder equal a half glass of wine or 1 pound of grapes, which is equivalent to three dietary servings of grapes, according to the USDA.

The wine has alcohol that will increase your risk of some cancers. Grape juice might be more effective.

My general take on studies about specific foods is that they typically are too short in duration and each food has such limited effect that we can't tell whether eating that food for years and years will increase your odds of survival. Remember, you can reduce your risk of a single disease but as a side effect increase your risk of something else. Or maybe you weren't at much risk of, say, colon cancer in the first place.

Whereas studies about whole categories of foods (e.g. vegetables and fruits) typically involve larger groups of people for longer periods of time. So we can state with some confidence that eating lots of fruits and vegetables will increase your life expectancy. But how much of the benefit is coming from particular fruits or vegetables is less clear.

Some of the benefit of fruits and vegetables is probably coming from a displacement effect. The fruits and vegetables displace less healthy foods from the diet. Eat a lot of vegetables and therefore eat less white flour and other refined high glycemic index foods.

By Randall Parker    2007 November 23 02:22 PM   Entry Permalink | Comments (0)
2007 November 01 Thursday
High Blood Sugar Increases Colorectal Cancer Risk

Here's yet another reason to get lots of exercise, control your weight, and eat a low glycemic index and unrefined diet: The higher blood sugar that comes from eating a highly refined diet and from being a couch potato puts you at greater risk of colon cancer.

The glucose levels observed by researchers in the Polyp Prevention Trial, of which this study was a subset analysis, and the levels of exposure that led to the increased risk, were not unusually elevated. Researchers used a glucose concentration of 99 mg/dl as the cut point for the patients in the high group in the study; a fasting blood glucose level between 100 and 125 mg/dl signals pre-diabetes. The levels used in the study are reflective of those in the general U.S. population, therefore it is important to note that even a modest elevation of fasting glucose can affect a patient’s risk of colorectal cancer.

Patients who presented with the highest levels of both insulin and glucose had an approximately 50 percent increased risk of colorectal tumor recurrence. The Polyp Prevention Trial found a recurrence for colorectal tumors of 39.6 percent over four years, meaning the recurrence rate in this subset of patients represents a large increase in absolute risk. Patients who had a high concentration of glucose experienced more than 2.4 times increased odds of advanced tumor recurrence. The subjects with the highest glucose concentration also tended to be slightly older and have higher body mass index (BMI) and waist to hip ratios. Additionally, they were more likely to be male, current smokers, a member of a minority group and less likely to have advanced beyond a high school education. For those without a family history of colorectal cancer, researchers observed an even greater risk with elevated concentrations of insulin and glucose compared to the overall study population.

Shift your diet toward vegetables, fruits, beans, and other healthier foods. If you must eat grains then eat whole grains. I realize you know all this. But reminders are helpful.

By Randall Parker    2007 November 01 05:23 PM   Entry Permalink | Comments (1)
2007 October 30 Tuesday
Vitamin D Only Reduces Colorectal Cancer?

Does vitamin D reduce the risk of many types of cancer as many studies suggest? A new study finds that high vitamin D in blood serum only reduces the risk of colorectal cancer.

No relationship was found between vitamin D levels and the overall risk of dying from cancer, according to a study published online October 30 in the Journal of the National Cancer Institute. However, higher vitamin D levels were associated with a decreased risk of colorectal cancer death.

Several epidemiological studies have supported the hypothesis that vitamin D can reduce cancer mortality by decreasing cancer incidence or improving survival. Animal and cell studies suggest that vitamin D may reduce tumor growth and induce cancer cell death. Diet and exposure to sunlight are the major sources of vitamin D.

D. Michal Freedman, Ph.D., of the National Cancer Institute in Bethesda, Md., and colleagues analyzed data from the third national Health and Nutrition Examination Survey to examine the relationship between levels of circulating vitamin D in the blood and cancer mortality in a group of 16,818 participants aged 17 and older.

After about a decade of follow-up, 536 participants had died of cancer. Cancer mortality was not related to the level of circulating vitamin D for the overall group, nor was it related when the researchers looked at the data by sex, race, or age. But higher levels of vitamin D (80 nmol/L or more) were associated with a 72 percent reduced risk of colorectal cancer mortality, compared with lower levels (less than 50 nmol/L).

“To our knowledge, this study is the first to examine the relationship between measured serum vitamin D levels and cancer mortality for selected site and for all sites combined,” the authors write.

A single study can't decisively resolve this question. Fortunately, other studies on vitamin D and total cancer risk are underway.

"Among the questions to be addressed in future studies is the relationship between vitamin D levels and future cancer risk both for individual cancer sites and for total cancer risk." The NCI and other institutes currently have a number of these studies underway, Freedman said.

A previous study found a negative association between blood serum vitamin D and both breast and colorectal cancer.

Keep in mind that vitamin D delivers other health benefits: Vitamin D Supplements Lower Risk Of Death, Low Vitamin D Linked To More Hip Fractures In Women, Low Vitamin D Ups Chronic Back Pain?, and Low Vitamin D Speeds Muscle Decline In Old Age?

By Randall Parker    2007 October 30 09:32 PM   Entry Permalink | Comments (0)
2007 October 18 Thursday
Sun Exposure Reduces Breast Cancer Risk?

Yet another study on the anti-cancer effects of vitamin D.

A research team from the Northern California Cancer Center, the University of Southern California, and Wake Forest University School of Medicine has found that increased exposure to sunlight – which increases levels of vitamin D in the body -- may decrease the risk of advanced breast cancer.

In a study reported online this week in the American Journal of Epidemiology, the researchers found that women with high sun exposure had half the risk of developing advanced breast cancer, which is cancer that has spread beyond the breast, compared to women with low sun exposure. These findings were observed only for women with naturally light skin color. The study defined high sun exposure as having dark skin on the forehead, an area that is usually exposed to sunlight.

The scientists used a portable reflectometer to measure skin color on the underarm, an area that is usually not directly exposed to sunlight. Based on these measurements, they classified the women as having light, medium or dark natural skin color. Researchers then compared sun exposure between women with breast cancer and those without breast cancer. Sun exposure was measured as the difference in skin color between the underarm and the forehead.

In women with naturally light skin pigmentation, the group without breast cancer had significantly more sun exposure than the group with breast cancer. The fact that this difference occurred only in one group suggests that the effect was due to differences in vitamin D production – and wasn’t just because the women were sick and unable to go outdoors. In addition, the effect held true regardless of whether the cancer was diagnosed in the summer or in the winter. The difference was seen only in women with advanced disease, suggesting that vitamin D may be important in slowing the growth of breast cancer cells.

“We believe that sunlight helps to reduce women’s risk of breast cancer because the body manufactures the active form of vitamin D from exposure to sunlight,” said Esther John, Ph.D., lead researcher on the study from the Northern California Cancer Center. “It is possible that these effects were observed only among light- skinned women because sun exposure produces less vitamin D among women with naturally darker pigmentation.”

You can get vitamin D from fish or a pill too.

By Randall Parker    2007 October 18 10:53 PM   Entry Permalink | Comments (18)
2007 September 26 Wednesday
Several Micronutrients Do Not Lower Prostate Cancer Risk

Lycopene was hyped as a potential risk reducer for prostate cancer. But then studies came out suggesting that maybe it doesn't help after all. The real answer has remained less than totally clear. The European Prospective Investigation into Cancer and Nutrition, being a pretty decent sounding prospective study, might provide the answer: lycopene and a bunch of anti-oxidant micronutrients don't appear to lower prostate cancer risks.

Objective: We aimed to examine the associations between plasma concentrations of 7 carotenoids, retinol, alpha-tocopherol, and gamma-tocopherol and prostate cancer risk.

Design: A total of 137 001 men in 8 European countries participated. After a mean of 6 y, 966 incident cases of prostate cancer with plasma were available. A total of 1064 control subjects were selected and were matched for study center, age, and date of recruitment. The relative risk of prostate cancer was estimated by conditional logistic regression, which was adjusted for smoking status, alcohol intake, body mass index, marital status, physical activity, and education level.

Results: Overall, none of the micronutrients examined were significantly associated with prostate cancer risk. For lycopene and the sum of carotenoids, there was evidence of heterogeneity between the associations with risks of localized and advanced disease. These carotenoids were not associated with the risk of localized disease but were inversely associated with the risk of advanced disease. The risk of advanced disease for men in the highest fifth of plasma concentrations compared with men in the lowest fifth was 0.40 (95% CI: 0.19, 0.88) for lycopene and 0.35 (95% CI: 0.17, 0.78) for the sum of carotenoids.

Conclusions: We observed no associations between plasma concentrations of carotenoids, retinol, or tocopherols and overall prostate cancer risk. The inverse associations of lycopene and the sum of carotenoids with the risk of advanced disease may involve a protective effect, an association of dietary choice with delayed detection of prostate cancer, reverse causality, or other factors.

I really wish they had looked at plasma vitamin D concentrations.

Taking most micronutrients in pills (vitamin D being a notable exception) doesn't serve as a substitute for eating foods that are health promoting or for avoiding foods that seem to harm health. You need to eat lots of fruits and vegetables and eat less highly fatty charbroiled beef. There's no pill substitute for avoiding saturated fats or for eating lower glycemic index foods. Macronutrients matter.

By Randall Parker    2007 September 26 09:59 PM   Entry Permalink | Comments (1)
2007 September 01 Saturday
Resveratrol Reduces Prostate Cancer In Mice

Resveratrol continues to be the supplement which I'm not taking that I most wonder whether I should be taking. Resveratrol appears to confer some protection against prostate cancer.

BIRMINGHAM, Ala. – Researchers at the University of Alabama at Birmingham (UAB) have found that nutrients in red wine may help reduce the risk of developing prostate cancer.

The study involved male mice that were fed a plant compound found in red wine called resveratrol, which has shown anti-oxidant and anti-cancer properties. Other sources of resveratrol in the diet include grapes, raspberries, peanuts and blueberries.

In the study resveratrol-fed mice showed an 87 percent reduction in their risk of developing prostate tumors that contained the worst kind of cancer-staging diagnosis. The mice that proved to have the highest cancer-protection effect earned it after seven months of consuming resveratrol in a powdered formula mixed with their food.

Other mice in the study, those fed resveratrol but still developed a less-serious form of prostate cancer, were 48 percent more likely to have their tumor growth halted or slowed when compared to mice who did not consume the compound, the UAB research team said.

A pair of recent articles from MIT's Technology Review provide a broader look at the science and commercial development efforts around resveratrol. At Harvard Medical School researcher David Sinclair believes resveratrol might extend our lives.

Sinclair's basic claim is simple, if seemingly improb­able: he has found an elixir of youth. In his Australian drawl, the 38-year-old Harvard University professor of pathology explains how he discovered that resveratrol, a chemical found in red wine, extends life span in mice by up to 24 percent and in other animals, including flies and worms, by as much as 59 percent. Sinclair hopes that resveratrol will bump up the life span of people, too. "The system at work in the mice and other organisms is evolutionarily very old, so I suspect that what works in mice will work in humans," he says.

Sinclair has co-founded a biotech start-up, Sirtris Pharmaceuticals, to try to develop variations on resveratrol to develop them into drugs.

Sinclair and a few other researchers involved in biotech start-ups around Boston argue that drugs can turn on the same genes that calorie restriction activates and thereby extend life just like calorie restriction does.

Only 20 years ago, aging was considered too complex for pharmacological intervention, involving thousands of genes and pathways. However, geneticists studying model organisms such as yeast and worms discovered several genes that can dramatically extend healthy life span1. There are proaging genes such as IGF-1 and antiaging genes such as SIRT1.

While genes that control aging have only recently been discovered, scientists have known for many decades that a simple change in diet can dramatically slow the pace of aging. "Calorie restriction" (CR), the diet wherein calories are reduced 20 to 40 percent, is the most robust means of extending healthy life span in mammals, and several of the key longevity pathways seem to underlie the beneficial effects of this diet. CR also improves health parameters in higher organisms including humans3.

There is controversy over whether calorie restriction delivers its benefits via SIRT1 activation. Researchers are chasing other genes as activators of CR's life extending effects. But resveratrol might deliver benefits even if it does not do so by emulating CR.

By Randall Parker    2007 September 01 07:56 PM   Entry Permalink | Comments (3)
2007 August 21 Tuesday
Vitamin D Can Reduce Breast And Colorectal Cancer

Vitamin D is the vitamin whose increased supplementation stands the best chances of reducing the incidence of major diseases. Here's more evidence for the cancer risk reduction achievable if only more people got enough daily vitamin D.

A new study looking at the relationship between vitamin D serum levels and the risk of colon and breast cancer across the globe has estimated the number of cases of cancer that could be prevented each year if vitamin D3 levels met the target proposed by researchers.

Cedric F. Garland, Dr.P.H., cancer prevention specialist at the Moores Cancer Center at the University of California, San Diego (UCSD) and colleagues estimate that 250,000 cases of colorectal cancer and 350,000 cases of breast cancer could be prevented worldwide by increasing intake of vitamin D3, particularly in countries north of the equator.  Vitamin D3 is available through diet, supplements and exposure of the skin to sunlight.

“For the first time, we are saying that 600,000 cases of breast and colorectal cancer could be prevented each year worldwide, including nearly 150,000 in the United States alone,” said study co-author Garland.   The paper, which looks at the dose-response relationship between vitamin D and cancer, will be published in the August edition of the journal Nutrition Reviews.

The study combined data from surveys of serum vitamin D levels during winter from 15 countries.  It is the first such study to look at satellite measurements of sunshine and cloud cover in countries where actual blood serum levels of vitamin D3 had also been determined.  The data were then applied to 177 countries to estimate the average serum level of a vitamin D metabolite of people living there.

The data revealed an inverse association of serum vitamin D with risk of colorectal and breast cancer.  The protective effect began at levels ranging from 24 to 32 nanograms per milliliter of 25-hydroxyvitamin D concentration in the serum.  The 25-hydroxyvitamin D level is the main indicator of vitamin D status.  The late winter average 25-hydroxyvitamin D in the US is about 15-18 ng/ml. The researchers maintain that increasing vitamin D levels in populations, particularly those in northern climates, has the potential to both prevent and possibly serve as an adjunct to existing treatments for cancer.

The work builds on previous studies by Garland and colleagues (Journal of Steroid Biochemistry and Molecular, February 2007) which found that raising the serum 25(OH)D levels to 55 ng/mL was optimal for cancer prevention.  This is the first study to recommend optimal vitamin D serum levels which, Garland said, are high enough to provide the needed benefit but which have been found by other scientists to be low enough to avoid health risks.

They recommend 2000 IU of vitamin D per day.

“This could be best achieved with a combination of diet, supplements and short intervals – 10 or 15 minutes a day – in the sun,” said Garland.  It could be less for very fair-skinned individuals. He went on to say that “the appropriate dose of vitamin D in order to reach this level, could be very little in a lifeguard in Southern California… or quite a lot for someone in Northern Europe who tends to remain indoors most of the year.” 

The serum level recommended by the study would correspond to intake of 2000 International Units per day of vitamin D3 for a meaningful reduction in colorectal cancer. The researchers recommend 2000 IU/day, plus, when weather allows, a few minutes in the sun with at least 40% of the skin exposed, for a meaningful reduction in breast cancer incidence, unless the individual has a history of skin cancer or a photosensitivity disease.

Unless you are taking supplements or spend a lot of time outdoors even in the winter you probably do not get enough vitamin D.

By Randall Parker    2007 August 21 06:27 PM   Entry Permalink | Comments (7)
2007 August 20 Monday
Broccoli Compound Boosts Immune System Against Cancer?

Eat cruciferous vegetables to boost your immune system.

Berkeley -- A compound found in broccoli and related vegetables may have more health-boosting tricks up its sleeves, according to a new study led by researchers at the University of California, Berkeley.

Veggie fans can already point to some cancer-fighting properties of 3,3'-diindolylmethane (DIM), a chemical produced from the compound indole-3-carbinol when Brassica vegetables such as broccoli, cabbage and kale are chewed and digested. Animal studies have shown that DIM can actually stop the growth of certain cancer cells.

This new study in mice, published online today (Monday, Aug. 20) in the Journal of Nutritional Biochemistry, shows that DIM may help boost the immune system as well.

"We provide clear evidence that DIM is effective in augmenting the immune response for the mice in the study, and we know that the immune system is important in defending the body against infections of many kinds and cancer," said Leonard Bjeldanes, UC Berkeley professor of toxicology and principal investigator of the study. "This finding bodes well for DIM as a protective agent against major human maladies."

Previous studies led by Bjeldanes and Gary Firestone, UC Berkeley professor of molecular and cell biology, have shown that DIM halts the division of breast cancer cells and inhibits testosterone, the male hormone needed for growth of prostate cancer cells.

In the new study, the researchers found increased blood levels of cytokines, proteins which help regulate the cells of the immune system, in mice that had been fed solutions containing doses of DIM at a concentration of 30 milligrams per kilogram. Specifically, DIM led to a jump in levels of four types of cytokines: interleukin 6, granulocyte colony-stimulating factor, interleukin 12 and interferon-gamma.

The scientists think the immune boosting effect of DIM might be one of the reasons why cruciferous vegetables seem to reduce the incidence of cancer.

"It is well-known that the immune system can seek out and destroy tumor cells, and even prevent tumor growth," said Xue. "An important type of T cell, called a T killer cell, can directly kill certain tumor cells, virally infected cells and sometimes parasites. This study provides strong evidence that could help explain how DIM blocks tumor growth in animals."

DIM was also able to induce higher levels of reactive oxygen species (ROS), substances which must be released by macrophages in order to kill some types of bacteria as well as tumor cells. The induction of ROS - three times that of a control culture - after DIM was added to the cell culture signaled the activation of macrophages, the researchers said.

"The effects of DIM were transient, with cytokine and lymphocyte levels going up and then down, which is what you'd expect with an immune response," said Bjeldanes. "Interestingly, to obtain the effects on the immune response, DIM must be given orally, not injected. It could be that the metabolism of the compound changes when it is injected instead of eaten."

I get a lot of people asking me what is the ideal diet. My answer: the kind of diet you probably don't like. That's the problem with the diet research. Mostly it turns up more reasons to eat huge amounts of vegetables. People don't want to hear that answer.

By Randall Parker    2007 August 20 10:53 PM   Entry Permalink | Comments (7)
2007 August 19 Sunday
Purple Corn And Chokeberries Against Colon Cancer

Anthocyanins which give many fruits and vegetables their colors have anti-cancer properties.

COLUMBUS, Ohio – Understanding the molecular structures of compounds that give certain fruits and vegetables their rich colors may help researchers find even more powerful cancer fighters, a new study suggests.

Evidence from laboratory experiments on rats and on human colon cancer cells also suggests that anthocyanins, the compounds that give color to most red, purple and blue fruits and vegetables appreciably slow the growth of colon cancer cells.

The findings also bring scientists a step closer to figuring out what exactly gives fruits and vegetables their cancer-fighting properties.

“These foods contain many compounds, and we're just starting to figure out what they are and which ones provide the best health benefits,” said Monica Giusti, the lead author of the study and an assistant professor of food science at Ohio State University.

The plants vary both in the amount of anthocyanins they contain and in which particular anthocyanins they contain. The anthocyanins vary in their anti-cancer properties. Since they mostly do not get absorbed they seem like a fairly safe way to cut down on colon cancer risk.

If yellow corn is less potent than blue corn then do we need to get back to multi-colored corn?

The researchers determined the amount of extract needed from each plant to cut the growth of human colon cancer cells in half. Altering pigment structures slightly by adding an extra sugar or acid molecule changed the biological activity of these extracts.

The researchers added different extracts to flasks that contained colon cancer cells. They used an analytical technique called high-performance liquid chromatography – mass spectrometry in order to determine the exact chemical structure of each compound. They used biological tests to determine the number of cancer cells left after anthocyanin treatment.

The researchers found that the amount of anthocyanin extract needed to reduce cancer cell growth by 50 percent varied among the plants. Extract derived from purple corn was the most potent, in that it took the least amount of this extract (14 micrograms per milliliter of cell growth solution) to cut cell numbers in half. Chokeberry and bilberry extracts were nearly as potent as purple corn. Radish extract proved the least potent, as it took nine times as much (131 µg/ml) of this compound to cut cell growth by 50 percent.

“All fruits and vegetables that are rich in anthocyanins have compounds that can slow down the growth of colon cancer cells, whether in experiments in laboratory dishes or inside the body,” Giusti said.

In additional laboratory studies, she and her colleagues found that anthocyanin pigments from radish and black carrots slowed the growth of cancer cells anywhere from 50 to 80 percent. But pigments from purple corn and chokeberries not only completely stopped the growth of cancer cells, but also killed roughly 20 percent of the cancer cells while having little effect on healthy cells.

Note that they are not using whole corn or whole berries. So an ounce of blue corn won't necessarily have more potent anti-colon cancer activity than an ounce of radishes. We need to know what the concentration of the most active anthocyanin compounds are in each of these foods in order to say which will deliver the most benefit. Still, blue corn muffins or pancakes with berries for breakfast might reduce your odds of dying from colon cancer.

If you know someone recently diagnosed with colon cancer note that dietary changes can make a big difference on outcomes. Also see my post Western Diet Boosts Colon Cancer Recurrence.

In the long run genetic engineering of plants to boost their levels of the most potent anti-cancer anthocyanins seems like the ticket.

By Randall Parker    2007 August 19 09:15 AM   Entry Permalink | Comments (1)
2007 August 14 Tuesday
Western Diet Boosts Colon Cancer Recurrence

Eat less of the bad foods and more of the good foods.

Patients treated for colon cancer who had a diet high in meat, refined grains, fat and desserts had an increased risk of cancer recurrence and death compared with patients who had a diet high in fruits and vegetables, poultry and fish, according to a study in the August 15 issue of JAMA.

But most people really like meat, refined grains, fat, and desserts. What good is this research result when it tells people to ignore their cravings?

Previous research has indicated that diet and other lifestyle factors have a significant influence on the risk of developing colon cancer. However, few studies have assessed the influence of diet on colon cancer recurrence and survival, according to background information in the article.

Jeffrey A. Meyerhardt, M.D., M.P.H., of the Dana-Farber Cancer Institute, Boston, and colleagues examined the influence of two distinct dietary patterns on cancer recurrence and survival in a group of 1,009 stage III colon cancer patients (cancer present in the colon and lymph nodes) enrolled in a clinical trial of postoperative chemotherapy in addition to other treatment. Patients reported dietary intake using a food frequency questionnaire during and six months after supplemental chemotherapy. Two major dietary patterns were identified, prudent and Western. The prudent pattern was characterized by high intakes of fruits and vegetables, poultry, and fish; the Western pattern was characterized by high intakes of meat, fat, refined grains, and dessert.

Patients were followed up for cancer recurrence or death. During a median (midpoint) follow-up of 5.3 years, 324 patients had cancer recurrence, 223 patients died with cancer recurrence, and 28 died without documented cancer recurrence.

Recurrence rates are way higher if you eat a bad Western diet.

The researchers found that a higher intake of a Western dietary pattern after cancer diagnosis was associated with a significant increase in the risk of cancer recurrence or death. Compared with patients in the lowest Western dietary pattern quintile (bottom 20 percent), those in the highest quintile (top 20 percent) experienced a 3.3 times higher risk for cancer recurrence or death. Patients in the highest quintile of Western dietary pattern were 2.9 times more likely to have cancer recur than those in the lowest quintile. Similarly, a significantly higher overall risk of death with increasing Western dietary pattern was observed. In contrast, the prudent dietary pattern was not significantly associated with cancer recurrence or death.

Increased insulin production on the Western diet might be the cause of the worse outcome.

A “prudent” pattern characterized by high intakes of fruits and vegetables, poultry, and fish, and a “Western” pattern characterized by high amounts of red and processed meats, sweets and desserts, French fries, and refined grains. Participants didn’t fall neatly into one category or the other, but were scored in each by how closely they matched the Western and prudent models.

The survival benefit for those whose diets least resembled the Western pattern held true even after researchers controlled for factors such as gender, age, body mass, degree of cancer spread to lymph nodes, and physical activity level. Investigators do not know why such a diet is associated with a poorer outcome, but speculate that it may be related to increased insulin levels and insulin-like growth factors. Insulin and related growth factors have been linked to the formation and growth of some types of tumors.

Eat a lower glycemic index diet. Or watch metastatic colon cancer lodge in your bones and cause excruciating pain until you die an emaciated shadow of your former self. Hey, I'm not going to sugar coat the news for you. Doing that would boost your insulin level. I'm trying to write a low insulin blog here.

Fruits and veggies do not lower the rate of recurrence of all types of cancers though. Fruits and veggies failed to lower breast cancer recurrence in a recent study (more here and here).

By Randall Parker    2007 August 14 11:10 PM   Entry Permalink | Comments (0)
2007 August 01 Wednesday
Cruciferous Vegetables Slash Prostate Cancer Risk

Cruciferous vegetables cut prostate cancer risk by 40% overall.

Writing in the Journal of the National Cancer Institute, researchers from Canada and the US report that an increased intake of cruciferous vegetables was associated with a 40 per cent reduction in prostate cancer risk, with broccoli and cauliflower singled out as offering most protection.

Cauliflower is the most effective with a 52% decline in aggressive prostate cancer among men who eat cauliflower more than once a week.

Men who reported eating cauliflower more than once per week were 52 percent less likely to be diagnosed with aggressive prostate cancer than men who reported eating cauliflower less than once a month.

Men who reported eating broccoli more than once per week were 45 percent less likely to be diagnosed with aggressive prostate cancer than men who reported eating broccoli less than once a month.

Eat more cabbage, cauliflower, kale, collars, rutabaga, kohlrabi, Brussel sprouts, and other members of the Brassicaceae (aka Cruciferae) family of veggies.

Update: Eat some turmeric on that cauliflower.

Rutgers researchers have found that the curry spice turmeric holds real potential for the treatment and prevention of prostate cancer, particularly when combined with certain vegetables.

The scientists tested turmeric, also known as curcumin, along with phenethyl isothiocyanate (PEITC), a naturally occurring substance particularly abundant in a group of vegetables that includes watercress, cabbage, winter cress, broccoli, Brussels sprouts, kale, cauliflower, kohlrabi and turnips. "The bottom line is that PEITC and curcumin, alone or in combination, demonstrate significant cancer-preventive qualities in laboratory mice, and the combination of PEITC and curcumin could be effective in treating established prostate cancers," said Ah-Ng Tony Kong, a professor of pharmaceutics at Rutgers, The State University of New Jersey.

By Randall Parker    2007 August 01 11:34 PM   Entry Permalink | Comments (0)
2007 June 30 Saturday
Diet Factors Against Prostate Cancer

Here's a tour through a large assortment of studies on dietary and lifestyle factors that influence prostate cancer risks. Men who are willing to implement most of the recommendations here would greatly decrease their odds of getting prostate cancer. Note that many of the changes (e.g. less omega 6 fatty acids, more omega 3 fatty acids, less meat, more vegetables, more fruit, more vitamin D) would reduce the risks of other forms of cancer as well. Daily ground flaxseed made diagnosed prostate cancer cells less vigorous.

The researchers will present their results on Saturday, June 2, during a news briefing at the annual meeting of the American Society of Clinical Oncology, in Chicago. The multisite study, which was funded by the National Institutes of Health, also involved researchers at the University of Michigan and the University of North Carolina at Chapel Hill.

In the study, the researchers examined the effects of flaxseed supplementation on men who were scheduled to undergo prostatectomy -- surgery for the treatment of prostate cancer. The men took 30 grams of flaxseed daily for an average of 30 days prior to surgery. Once the men's tumors were removed, the researchers looked at tumor cells under a microscope, and were able to determine how quickly the cancer cells had multiplied.

Men taking flaxseed, either alone or in conjunction with a low-fat diet, were compared to men assigned to just a low-fat diet, as well as to men in a control group, who did not alter or supplement their daily diet. Men in both of the flaxseed groups had the slowest rate of tumor growth, Demark-Wahnefried said. Each group was made up of about 40 participants.

Study participants took the flaxseed in a ground form because flaxseed in its whole form has an undigestible seed coat, she said. Participants elected to mix it in drinks or sprinkle it on food, such as yogurt.

You'd probably need to get a seed grinder to make the ground seed once or twice a week. Though maybe freezing would let you make it less often.

Cut back on the omega 6 fatty acids found in vegetable oils and meats and eat more omega 3 fatty acids from fish.

Nutritionists recommend that people consume equal proportions of omega-3 and omega-6 PUFA. However, in current western diets, the proportion of omega-6 to omega-3 is between 30 and 50 to one.

The mice were fed either a diet high in omega-3 (ratio of omega-6 to omega-3 was 1:1) a diet low in omega 3 (ratio omega-6 to omega-3 was 20:1), or a diet high in omega-6 (ratio of omega-6 to omega-3 was 40:1). The scientists compared survival rates and weighed the animals’ prostates to measure tumor progression.

Mice with the tumor suppressor gene remained free of tumors and had 100 percent survival, regardless of diet. In mice with the gene defect, survival was 60 percent in animals on the high omega-3 diet, 10 percent in those on the low omega-3 diet and 0 percent in those on the high omega-6 diet.

“This suggests that if you have good genes, it may not matter too much what you eat,” said Chen, a professor of cancer biology. “But if you have a gene that makes you susceptible to prostate cancer, your diet can tip the balance. Our data demonstrate the importance of gene-diet interactions, and that genetic cancer risk can be modified favorable by omega-3 PUFA.”

Pomegranate slows prostate cancer in mice.

The research team then progressed to tests in mice that had been injected with prostate cancer cells from humans and developed malignancies. The 24 mice were randomly divided into three groups. The control group received normal drinking water, while the animals in the second and third groups had their drinking water supplemented with .1 percent and .2 percent pomegranate extract respectively. The doses for the mice were chosen to parallel how much pomegranate juice a typical healthy human might be willing to eat or drink daily.

The results were dramatic: the mice receiving the higher concentration of pomegranate extract showed significant slowing of their cancer progression and a decrease in the levels of prostate-specific antigen (PSA), a marker used to indicate the presence of prostate cancer in humans. The animals that received only water had tumors that grew much faster than those in the animals treated with pomegranate extract.

Pomegranate juice also slows prostate cancer growth in men.

Drinking an eight ounce glass of pomegranate juice daily increased by nearly four times the period during which PSA levels in men treated for prostate cancer remained stable, a three-year UCLA study has found.

The study involved 50 men who had undergone surgery or radiation but quickly experienced increases in prostate-specific antigen or PSA, a biomarker that indicates the presence of cancer. UCLA researchers measured "doubling time," how long it takes for PSA levels to double, a signal that the cancer is progressing, said Dr. Allan Pantuck, an associate professor of urology, a Jonsson Cancer Center researcher and lead author of the study.

Inositol hexaphosphate found in high fiber foods reduces prostate cancer tumor size.

Compound found in high-fiber foods shows promise against prostate cancer — A dietary component found in most whole grain foods, beans, nuts and other high-fiber items shows promise in animal studies as a potent weapon for preventing prostate cancer. The compound, inositol hexaphosphate (IP6), was fed to animal models of prostate cancer and resulted in up to a 66 percent reduction in tumor size in comparison to control animals that were given water instead, the researchers say.

Turmeric and cauliflower against prostate cancer.

Rutgers researchers have found that the curry spice turmeric holds real potential for the treatment and prevention of prostate cancer, particularly when combined with certain vegetables.

The scientists tested turmeric, also known as curcumin, along with phenethyl isothiocyanate (PEITC), a naturally occurring substance particularly abundant in a group of vegetables that includes watercress, cabbage, winter cress, broccoli, Brussels sprouts, kale, cauliflower, kohlrabi and turnips. "The bottom line is that PEITC and curcumin, alone or in combination, demonstrate significant cancer-preventive qualities in laboratory mice, and the combination of PEITC and curcumin could be effective in treating established prostate cancers," said Ah-Ng Tony Kong, a professor of pharmaceutics at Rutgers, The State University of New Jersey.

A daily glass of red wine reduces prostate cancer risk.

SEATTLE – Drinking a glass of red wine a day may cut a man's risk of prostate cancer in half, and the protective effect appears to be strongest against the most aggressive forms of the disease, according to a new study led by investigators at Fred Hutchinson Cancer Research Center.

Diet and lifestyle changes might be enough to stop or reverse prostate cancer.

The study was directed by Dean Ornish, MD, clinical professor, and Peter Carroll, MD, chair of the Department of Urology, both of the University of California, San Francisco, and the late William Fair, MD, chief of urologic surgery and chair of urologic oncology, Memorial Sloan-Kettering Cancer Center.

The research team studied 93 men with biopsy-proven prostate cancer who had elected not to undergo conventional treatment for reasons unrelated to this study. The participants were randomly divided into either a group who were asked to make comprehensive changes in diet and lifestyle or a comparison group who were not asked to do so.

After one year, the researchers found that PSA levels (a protein marker for prostate cancer) decreased in men in the group who made comprehensive lifestyle changes but increased in the comparison group. There was a direct correlation between the degree of lifestyle change and the changes in PSA. Also, they found that serum from the participants inhibited prostate tumor growth in vitro by 70 percent in the lifestyle-change group but only 9 percent in the comparison group. Again, there was a direct correlation between the degree of lifestyle change and the inhibition of prostate tumor growth.

Participants in the lifestyle-change group were placed on a vegan diet consisting primarily of fruits, vegetables, whole grains, and legumes supplemented with soy, vitamins and minerals. They participated in moderate aerobic exercise, yoga/meditation, and a weekly support group session. A registered dietitian was available for consultation, and a nurse case manager contacted the participants once a week for the first three months and weekly thereafter.

Give up meat and dairy and eat lots of plants.

The study, published in the September issue of Integrative Cancer Therapies, focused on the change in the levels of prostate-specific antigen (PSA), an indicator of the cancer, in response to a plant-based diet and stress reduction. Patients were taught to increase consumption of plant-based foods such as whole grains, cruciferous and leafy green vegetables, beans and legumes, and fruit, and to decrease the intake of meat, dairy products, and refined carbohydrates. They were also provided with stress management training, which incorporated meditation, yoga and Tai Chi exercises. The plant-based diet and stress reduction were effective in significantly reducing the PSA rate, indicating a reduction in the rate of progression of the prostate cancer.

My guess is you'll be much better off if you avoid grains and just eat non-grain plants. I wonder if the stress management techniques contributed to the benefit.

The diet changes were made for men with early stage prostate cancer. But the smarter thing to do is to make the diet changes before you get prostate cancer.

Up to 73% of men with prostate cancer take nonprescription supplements, and smaller numbers use diet, exercise, or both in the hope of improving their outcome. Most of these men also receive conventional therapy, but a few depend on lifestyle alone. The appeal of lifestyle therapy is obvious—but does it work? Experts don’t know, though research raises hope that it may have a beneficial impact, reports the July 2007 issue of Harvard Men’s Health Watch.

All of the 93 men who signed up for the trial had newly diagnosed low- to moderate-grade cancers that were localized to the prostate gland. Half were randomly assigned to a lifestyle program, and half got no advice on lifestyle changes. The program that researchers created included four elements: An ultra-low-fat vegan diet; supplements, including soy, fish oil, vitamins E and C, and selenium; an exercise program of walking 30 minutes six days a week; and stress reduction that included yoga-based stretching, breathing, and meditation for an hour a day.

At the end of a year, a small but significant difference was evident. The average PSA in the intensive lifestyle group fell, whereas the average PSA in the untreated men rose. The participants in the lifestyle group also showed favorable cancer-fighting changes in their blood.

Keep your weight under control.

“I was very surprised by the findings,” said Kristal, member and associate head of the Cancer Prevention Program in the Hutchinson Center’s Public Health Sciences Division. “We found the prostate-cancer-specific mortality risk associated with obesity was similar regardless of treatment, disease grade or disease stage at the time of diagnosis,” he said. “If a man is obese at the time of diagnosis, he faces a 2.6-fold greater risk of dying as compared to a normal-weight man with the same diagnostic profile, regardless of whether he has a radical prostatectomy or radiation therapy, whether or not he gets androgen-deprivation therapy, whether he has low- or high-grade disease and whether he has localized, regional or distant disease,” Kristal said, referring to the degree of cancer spread.

The researchers also found that obese men diagnosed with local or regional disease – that is, disease that is confined to the prostate or has spread to into surrounding tissue – face a 3.6-fold increased risk of cancer spreading into distant organs, or metastasis, as compared to prostate-cancer patients of normal weight.

The message that soy reduces prostate cancer risk is perhaps an oversimplification.

PHILADELPHIA – The largest study examining the relationship between the traditional soy-rich Japanese diet and development of prostate cancer in Japanese men has come to a seemingly contradictory conclusion: intake of isoflavone chemicals, derived largely from soy foods, decreased the risk of localized prostate cancer but increased the risk of advanced prostate cancer.

The prospective study of 43,509 men, published in the March issue of Cancer Epidemiology, Biomarkers & Prevention, suggests that the effects of isoflavones on prostate cancer development may differ according to disease stage, say researchers at the National Cancer Center in Japan.

One possible explanation is that isoflavones may delay the progression of latent prostate cancer only; once tumors lose estrogen-receptor beta expression and become aggressive, isoflavones may fail to protect against the development of advanced cancer, and might even increase the risk of progression, possibly by reducing serum testosterone, researchers say. It is also possible that advanced and localized prostate cancer may be different tumor subtypes, which may react differently to isoflavones.

The message that lycopene in tomatoes reduces prostate cancer risk might not be true.

PHILADELPHIA -- Tomatoes might be nutritious and tasty, but don’t count on them to prevent prostate cancer. In the May issue of Cancer Epidemiology, Biomarkers & Prevention, researchers based at the National Cancer Institute and Fred Hutchinson Cancer Research Center report that lycopene, an antioxidant predominately found in tomatoes, does not effectively prevent prostate cancer. In fact, the researchers noted an association between beta-carotene, an antioxidant related to lycopene, and an increased risk for aggressive prostate cancer.

According to the researchers, the study is one of the largest to evaluate the role of blood concentrations of lycopene and other carotenoid antioxidants in preventing prostate cancer. Study data were derived from over 28,000 men enrolled in the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial, an ongoing, randomized National Cancer Institute trial to evaluate cancer screening methods and to investigate early markers of cancer.

Whether multivitamins provide a cancer risk reduction benefit is far from clear.

Karla Lawson, Ph.D., of the National Cancer Institute in Bethesda, Md., and colleagues followed 295,344 men enrolled in the National Institutes of Health-AARP Diet and Health Study to determine the association between multivitamin use and prostate cancer risk. After five years of follow-up, 10,241 men were diagnosed with prostate cancer, including 8,765 with localized cancers and 1,476 with advanced cancers.

The researchers found no association between multivitamin use and the risk of localized prostate cancer. But they did find an increased risk of advanced and fatal prostate cancer among men who used multivitamins more than seven times a week, compared with men who did not use multivitamins. The association was strongest in men with a family history of prostate cancer and men who also took selenium, beta-carotene, or zinc supplements.

As long term readers know by now, the cancer risk reduction benefit from vitamin D is much clearer than that from other vitamins. See the posts 60% Cancer Drop From Vitamin D Supplements and Vitamin D Could Decrease Overall Cancer Risk 30%.

The younger among you may be thinking that by the time you reach the high cancer risk years we'll have effective cures for cancer. A person in their 20s isn't going to die from cancer they get in the year 2047. But keep in mind that cancer is a consequence of accumulated cell damage. We'll have cures for cancer before we get full body rejuvenation therapies. A diet that reduces your risk of cancer will slow your body aging and therefore if you eat a cancer risk reduction diet you won't grow as old while waiting for the rejuvenation therapies.

By Randall Parker    2007 June 30 09:25 AM   Entry Permalink | Comments (11)
2007 June 10 Sunday
Calcium And Vitamin D Reduce Cancer In Women

Are you taking vitamin D yet? If not, here's yet another study finding a protective effect from vitamin D against cancer.

WASHINGTON, D.C. (June 8, 2007) – Key milk nutrients, calcium and vitamin D, may do more than just help keep your bones strong. Increasing intake of calcium and vitamin D could reduce the risk for cancer in women by at least 60 percent, according to a new study published in the American Journal of Clinical Nutrition. (1)

The four-year clinical trial included more than one thousand women over the age of 55 in one of three supplement groups: 1) calcium (1400-1500mg) plus vitamin D (1100 IU vitamin D) 2) calcium only (1400-1500 mg) or 3) a placebo. The researchers found that the risk of developing cancer was 60 percent lower for those who took calcium and vitamin D and 47 percent lower for those taking calcium alone, compared to the placebo.

Fifty women developed nonskin cancer through the course of the four-year study, including breast, colon, lung and other cancers. When researchers excluded the 13 cancers diagnosed during first year of the study, determining these cancers were likely present at the study onset, the protective effect of calcium and vitamin D was even greater, with a 77 percent lower risk for cancer for those taking calcium plus vitamin D compared to the placebo.

Taking the vitamin D and calcium long term might provide an even higher level of protection.

I found it interesting that calcium provides a protective effect and a substantial one. Almost all the studies I come across about the protective effect of vitamin D against cancer do not include a group that uses calcium. I wish this latest study had included a group that only took vitamin D. Then we'd know whether the calcium still provides a benefit on top of vitamin D.

By Randall Parker    2007 June 10 06:44 PM   Entry Permalink | Comments (4)
2007 June 02 Saturday
Vitamin D And Calcium Reduce Breast Cancer Risk

Dietary consumption of calcium and vitamin D reduce breast cancer but only before menopause.

Over an average of 10 years of follow-up, 276 premenopausal women and 743 postmenopausal women developed breast cancer. Calcium and vitamin D intake were moderately associated with a lower risk of breast cancer before but not after menopause. The inverse associated in premenopausal women appeared more pronounced for more aggressive breast tumors.

"A possible explanation for the evident difference by menopause status may be related to the joint relationship among calcium, vitamin D and insulinlike growth factors (IGFs)," they continue. "In vitro studies have suggested that calcium and vitamin D exert anticarcinogenic effects on breast cancer cells expressing high levels of IGF-1 and IGF binding protein 3. Calcium, vitamin D and IGF binding protein 3 have been shown in vitro to interact with each other in promoting growth inhibition in breast cancer cells." Since blood levels of these compounds decline with age, they would be more prevalent in younger, premenopausal women.

This result does not necessarily mean that vitamin D and calcium have no anti-cancer benefit as women get older. As we age we suffer decreased ability to absorb nutrients. Maybe older women do not absorb vitamin D well enough to benefit from concentrations found in food and maybe they need higher doses to achieve the same benefit as they get older.

By Randall Parker    2007 June 02 01:12 PM   Entry Permalink | Comments (2)
2007 May 16 Wednesday
Boiling Vegetables Reduces Anti-Cancer Benefits

Steaming, microwaving, and stir-frying are all much better than boiling.

The researchers, Prof Paul Thornalley from Warwick Medical School at the University of Warwick and Dr Lijiang Song from the University of Warwick’s Department of Chemistry bought Brassica vegetables, (broccoli, Brussel sprouts, cauliflower and green cabbage) from a local store and transported them to the laboratory within 30 minutes of purchasing. The effect of cooking on the glucosinolate content of vegetables was then studied by investigating the effects of cooking by boiling, steaming, microwave cooking and stir-fry.

Boiling appeared to have a serious impact on the retention of those important glucosinolate within the vegetables. The loss of total glucosinolate content after boiling for 30 minutes was: broccoli 77%, Brussel sprouts 58%, cauliflower 75% and green cabbage 65%.

The effects of other cooking methods were investigated: steaming for 0–20 min, microwave cooking for 0–3 min and stir-fry cooking for 0–5 min. All three methods gave no significant loss of total glucosinolate analyte contents over these cooking periods.

I'm big on eating raw cabbage as cole slaw. Stir-frying seems like the most attractive way to prepare the other Brassica (aka cruciferous) vegetables.

By Randall Parker    2007 May 16 10:52 PM   Entry Permalink | Comments (6)
2007 April 29 Sunday
60% Cancer Drop From Vitamin D Supplements

As regular readers know, I've been after you for years to raise your body vitamin D levels. If you haven't gotten off your duff yet to do anything about it how about this as something to get you going? A study coming out in June will report a more than halving of the incidence of cancer by taking vitamin D supplements.

But perhaps the biggest bombshell about vitamin D's effects is about to go off. In June, U.S. researchers will announce the first direct link between cancer prevention and the sunshine vitamin. Their results are nothing short of astounding.

A four-year clinical trial involving 1,200 women found those taking the vitamin had about a 60-per-cent reduction in cancer incidence, compared with those who didn't take it, a drop so large — twice the impact on cancer attributed to smoking — it almost looks like a typographical error.

How many people have doctors killed by advocating the avoidance of sun due to the risk of skin cancer?

How much would life expectancies rise if everyone got enough vitamin D?

One of the researchers who made the discovery, professor of medicine Robert Heaney of Creighton University in Nebraska, says vitamin D deficiency is showing up in so many illnesses besides cancer that nearly all disease figures in Canada and the U.S. will need to be re-evaluated. "We don't really know what the status of chronic disease is in the North American population," he said, "until we normalize vitamin D status."

Vitamin D could buy us some extra years while we try to stay alive waiting for rejuvenation therapies.

People are especially deficient during the winter.

Last month, a study of 7,500 men and women found that most don't have enough vitamin D in their bloodstream for at least six months of the year.

'By Easter, 90 per cent of the population are seriously depleted in the amount of vitamin D they have in their bodies,' says author of the study Dr Elina Hypponnen, of the Institute of Child Health in London.

As we get older and our skin ages it becomes less efficient at using light to catalyze the synthesis of vitamin D. So part of the rise in incidence of vitamin D with age is probably caused by worsening vitamin D deficiency.

Vitamin D might do what Linus Pauling claimed vitamin C could do: reduce the incidence of infections.

The malign consequences have been revealed by in a study from the United States which shows that boosting vitamin D may be the most effective way of warding off infections that cause winter colds.

The authors, from Winthrop University Hospital, Mineola, New York, who publish their findings in the journal Epidemiology and Infection, say vitamin D stimulates "innate immunity" by activating peptides in the body that attack bacteria, fungi and viruses.

"Vitamin D supplementation, particularly with higher doses, may protect against the typical winter cold and flu ... Since there is an epidemic of vitamin D insufficiency in the US, the public health impact of this observation could be great," they write.

Vitamin D deficiency is also linked to a higher incidence of auto-immune diseases. For example, multiple sclerosis occurs at higher rates in the more northern regions of North America where people get less sun in the winter due to both cold and shorter days.

The current max recommended limit of 2000 IU per day might be too low.

Calls to increase vitamin D intake have been growing. Indeed, only recently fifteen experts from universities, research institutes, and university hospitals around the world called for international agencies to "reassess as a matter of high priority" dietary recommendations for vitamin D because current advice is outdated and puts the public at risk of deficiency (The American Journal of Clinical Nutrition, Vol. 85, pp. 860-868).

A recent review of the science reported that the tolerable upper intake level for oral vitamin D3 should be increased five-fold, from the current tolerable upper intake level (UL) in Europe and the US of 2000 International Units (IU), equivalent to 50 micrograms per day, to 10,000 IU (250 micrograms per day).

I would suggest refraining from doses above 2000 IU, at least for now. Vitamin D research has become such a hot topic that we should expect more clarification on the risks and benefits of higher doses. But my guess from what I've read so far is that a 2000 IU dose daily is enough to provide the vast majority of the benefit.

Also see some of my previous posts on vitamin D: Vitamin D Could Decrease Overall Cancer Risk 30%, Higher Vitamin D Reduces Aging Bone Fracture Risks, Vitamin D Reduces Breast Cancer Risk, Vitamin D Crucial For Long Term Lung Health, and Vitamin D Confirmed To Reduce Multiple Sclerosis Risk.

By Randall Parker    2007 April 29 07:46 PM   Entry Permalink | Comments (34)
2007 March 26 Monday
Blueberries Reduce Colon Cancer Risk?

Blueberries and grapes contain a compound that lowers the incidence of colon cancer in rats.

Along with scientists Nanjoo Suh, also of Rutgers, and Agnes Rimando of the USDA’s Agricultural Research Service (ARS), Reddy and his associates conducted a small pilot study to determine the effect of pterostilbene on colon cancer. The study included 18 rats that were given a compound (azoxymethane) to induce colon cancer in a manner similar to human colon cancer development. Nine of the animals were then placed on a balanced daily diet, while the other nine were given the same diet supplemented with pterostilbene (at a level of 40 parts per million).

At the end of an eight-week study period, the rats that were fed pterostilbene showed 57 percent fewer pre-cancerous lesions in their colon in comparison to the control group, Reddy and his associates say. Pterostilbene also reduced colonic cell proliferation and inhibited certain genes involved in inflammation, both of which are considered colon cancer risk factors, the researchers say.

You can read the full paper online: Pterostilbene, an Active Constituent of Blueberries, Suppresses Aberrant Crypt Foci Formation in the Azoxymethane-Induced Colon Carcinogenesis Model in Rats. The full paper reports that pterostilbene has been found in blueberries, cranberries, sparkleberries, lingonberries, and grapes.

Pterostilbene lowers blood lipids and cancer. Some labs report that pterostilbene lowers blood glucose sugar levels as well.

Glucose levels in rats with hyperglycemia induced by streptozotocin were determined after i.p. administration of marsupsin (1), pterosupin (2), and pterostilbene (3), three important phenolic constituents of the heartwood of Pterocarpus marsupium. Marsupsin and pterostilbene significantly lowered the blood glucose level of hyperglycemic rats, and the effect was comparable to that of 1,1-dimethylbiguanide (metformin).

But you aren't going to get pterostilbene from wine because it appears to be too unstable to survive the wine-making process.

For reasons that are unclear, pterostilbene is not normally found in wine, Rimando says. This may be because it is unstable in light and air, which makes it less likely to survive the wine-making process, she says.

Pterostilbene and resveratrol are both antifungal compounds and they deliver some of same health benefits as each other.

This research provides yet more argument for eating more berries, grapes, and cherries. Eat the full fruit for maximal benefit rather than drinking juice.

By Randall Parker    2007 March 26 08:50 PM   Entry Permalink | Comments (3)
2007 February 10 Saturday
Vitamin D Cuts Colorectal Cancer Incidence

A meta-analysis of 5 studies found that higher blood vitamin D is associated with a 50% lower risk of colorectal cancer.

A larger daily dose of vitamin D could reduce the incidence of colorectal cancer with minimal risk, according to a new review that pools results from five studies.

The analysis found that maintaining a specific target blood level of vitamin D was associated with a 50 percent lower risk of colorectal cancer than that seen in people with consistently lower blood levels.

Previous studies had shown that lower blood levels of vitamin D did not protect against colorectal cancer, according to lead author Edward Gorham, Ph.D., a research epidemiologist with the Naval Health Research Center in San Diego. However, a meta-analysis pools the data from several studies, thus increasing the strength of the results.

I've been telling my regular readers about the benefits of vitamin D for years. A few of you are even acting on this information. Okay, what's with the rest of you? What are your excuses?

50%!

The researchers found that a blood serum vitamin D level of 33 nanograms per milliliter or higher was associated with a 50 percent lower risk of colorectal cancer than that seen with blood levels of 12 nanograms per milliliter or lower.

You would need to get between 1000 and 2000 IU of vitamin D per day to get this benefit. You can get there with a supplement or with daily sunbathing.

The amount of dietary vitamin D needed to reach the serum levels that appear to be protective against colorectal cancer — 1,000 to 2,000 international units a day — would not pose any risk, according to Gorham: “The Institute of Medicine has set a ‘No Adverse Effect Level’ of 2,000 IU per day for vitamin D intake, so this recommendation would be safe for most people.”

There is no official recommended dietary allowance for vitamin D, but an adequate dietary intake per day for most adults is currently considered to be 200 to 400 IU.

If you spend alot of time out in the sun during the summer you might only need the supplement during the colder months with the shorter days.

Small amounts of sun exposure would also help people boost their vitamin D levels. Fifteen to 20 minutes per day without sunscreen is enough for the body to synthesize 10,000 IU of vitamin D with minimal risk of sunburn or skin cancer, Gorham said.

Vitamin D will probably lower your risk of Multiple Sclerosis and your incidence of colds and flu too. I believe it is the vitamin that we'd get the most benefit from if we got more of it. Not saying there aren't people out there with plenty of D but not enough iron or zinc or folic acid or C. But for most people more D would deliver the biggest benefit.

Higher blood vitamin D also reduces breast cancer risk 50%.

The breast cancer study, published online in the current issue of the Journal of Steroid Biochemistry and Molecular Biology, pooled dose-response data from two earlier studies - the Harvard Nurses Health Study and the St. George's Hospital Study - and found that individuals with the highest blood levels of 25-hydroxyvitamin D, or 25(OH)D, had the lowest risk of breast cancer.

The researchers divided the 1,760 records of individuals in the two studies into five equal groups, from the lowest blood levels of 25(OH)D (less than 13 nanograms per milliliter, or 13 ng/ml) to the highest (approximately 52 ng/ml). The data also included whether or not the individual had developed cancer.

"The data were very clear, showing that individuals in the group with the lowest blood levels had the highest rates of breast cancer, and the breast cancer rates dropped as the blood levels of 25-hydroxyvitamin D increased," said study co-author Cedric Garland, Dr.P.H. "The serum level associated with a 50 percent reduction in risk could be maintained by taking 2,000 international units of vitamin D3 daily plus, when the weather permits, spending 10 to 15 minutes a day in the sun."

By Randall Parker    2007 February 10 12:34 PM   Entry Permalink | Comments (3)
2007 January 23 Tuesday
Fiber Against Breast Cancer

Ladies, eat more fiber to protect your breasts!

Pre-menopausal women who eat large amounts of fibre could halve their breast cancer risk, a UK study has suggested.

The University of Leeds researchers, who studied 35,000 women, found those who ate 30g of fibre a day had half the risk of those who ate less than 20g.

Also, reduce protein intake while increasing vitamin C intake.

257 pre-menopausal women developed breast cancer during the study, which was initially funded by the World Cancer Research Fund.

They were found to be women who had a greater percentage of energy derived from protein, and lower intakes of dietary fibre and vitamin C, compared to women who did not develop cancer.

Eat beans and berries. Eat whole grains. Vegetables too.

By Randall Parker    2007 January 23 11:23 PM   Entry Permalink | Comments (0)
Tomatoes And Broccoli Against Prostate Cancer

Broccoli and tomatoes shrink prostate cancer tumors in rats.

URBANA - A new University of Illinois study shows that tomatoes and broccoli--two vegetables known for their cancer-fighting qualities--are better at shrinking prostate tumors when both are part of the daily diet than when they're eaten alone.

"When tomatoes and broccoli are eaten together, we see an additive effect. We think it's because different bioactive compounds in each food work on different anti-cancer pathways," said University of Illinois food science and human nutrition professor John Erdman.

In a study published in the January 15 issue of Cancer Research, Erdman and doctoral candidate Kirstie Canene-Adams fed a diet containing 10 percent tomato powder and 10 percent broccoli powder to laboratory rats that had been implanted with prostate cancer cells. The powders were made from whole foods so the effects of eating the entire vegetable could be compared with consuming individual parts of them as a nutritional supplement.

Other rats in the study received either tomato or broccoli powder alone; or a supplemental dose of lycopene, the red pigment in tomatoes thought to be the effective cancer-preventive agent in tomatoes; or finasteride, a drug prescribed for men with enlarged prostates. Another group of rats was castrated.

After 22 weeks, the tumors were weighed. The tomato/broccoli combo outperformed all other diets in shrinking prostate tumors. Biopsies of tumors were evaluated at The Ohio State University, confirming that tumor cells in the tomato/broccoli-fed rats were not proliferating as rapidly. The only treatment that approached the tomato/broccoli diet's level of effectiveness was castration, said Erdman.

"As nutritionists, it was very exciting to compare this drastic surgery to diet and see that tumor reduction was similar. Older men with slow-growing prostate cancer who have chosen watchful waiting over chemotherapy and radiation should seriously consider altering their diets to include more tomatoes and broccoli," said Canene-Adams.

How much tomato and broccoli should a 55-year-old man concerned about prostate health eat in order to receive these benefits? The scientists did some conversions.

You'd need to eat a cup and a half of broccoli and a half cup of tomato paste to get a similar dose scaled up to human size. I do not see consumption of so much tomato paste as a problem. But the broccoli? Ugh.

"To get these effects, men should consume daily 1.4 cups of raw broccoli and 2.5 cups of fresh tomato, or 1 cup of tomato sauce, or ½ cup of tomato paste. I think it's very doable for a man to eat a cup and a half of broccoli per day or put broccoli on a pizza with ½ cup of tomato paste," said Canene-Adams.

What I want to know: Can cabbage serve in place of broccoli as a prostate cancer risk reducer?

Tomatoes reduce testosterone in rats. Do they have this effect in humans?

Another recent Erdman study shows that rats fed the tomato carotenoids phytofluene, lycopene, or a diet containing 10 percent tomato powder for four days had significantly reduced testosterone levels. "Most prostate cancer is hormone-sensitive, and reducing testosterone levels may be another way that eating tomatoes reduces prostate cancer growth," Erdman said.

I've long suspected that many common foods have pharmacological efffects. If a large study systematically put people on a variety of controlled diets with few foods each diet and then measured many hormones and other blood markers my guess is all sorts of interactions would pop up from the data. Lots of compounds in foods accidentally bind in locations in human bodies and cause changes in how our metabolisms function.

By Randall Parker    2007 January 23 11:20 PM   Entry Permalink | Comments (5)
2007 January 02 Tuesday
Olive Oil Lowers Oxidative Stress Marker

The ability of olive oil to lower a marker for oxidative damage of DNA in cells suggests that olive oil might lower the risk of cancer.

If you want to avoid developing cancer, then you might want to add eating more olive oil to your list of New Year's resolutions. In a study to be published in the January 2007 issue of The FASEB Journal, scientists from five European countries describe how the anti-cancer effects of olive oil may account for the significant difference in cancer rates among Northern and Southern Europeans.

The authors drew this conclusion based on the outcomes of volunteers from Denmark, Finland, Germany, Italy, and Spain, who consumed 25 milliliters (a little less than a quarter cup) of olive oil every day for three weeks. During this time, the researchers examined urine samples of the subjects for specific compounds known to be waste by-products of oxidative damage to cells, a precursor to cancer. At the beginning of the trial, the presence of these waste by-products was much higher in Northern European subjects than their Southern European counterparts. By the end of three weeks, however, the presence of this compound in Northern European subjects was substantially reduced.

"Determining the health benefits of any particular food is challenging because of it involves relatively large numbers of people over significant periods of time," said lead investigator Henrik E. Poulsen, M.D. of Rigshospitalet, Denmark. "In our study, we overcame these challenges by measuring how olive oil affected the oxidation of our genes, which is closely linked to development of disease. This approach allows us to determine if olive oil or any other food makes a difference. Our findings must be confirmed, but every piece of evidence so far points to olive oil being a healthy food. By the way, it also tastes great."

I'd like to see more dietary studies using oxidative stress markers as a quicker way to guess at the likely long term effects of various food choices.

The polyphenols in olive oil surprisingly do not look like the cause of the lowered oxidative stress marker.

Another interesting finding in the study suggests that researchers are just beginning to unlock the mysteries of this ancient "health food." Specifically, the researchers found evidence that the phenols in olive oil are not the only compounds that reduced oxidative damage. Phenols are known antioxidant compounds that are present in a wide range of everyday foods, such as dark chocolate, red wine, tea, fruits, and vegetables. Despite reducing the level of phenols in the olive oil, the study's subjects still showed that they were receiving the same level of health benefits.

I'd like to see studies done using different high phenol foods that are low in fat to see if any of the foods can lower oxidative stress using the same marker (8oxodG - sounds like an oxidized form of the nucleic acid guanine) that these researchers used.

The researchers measured the compound 8oxodG in the urine as an indicator of oxidative stress and damage and found olive oil lowered 8oxodG.

Oxidative damage is a process whereby the metabolic balance of a cell is disrupted by exposure to substances that result in the accumulation of free-radicals, which can then damage the cell.

The men were found to have around 13% less 8oxodG compared with their levels at the beginning of the study.

At the beginning of the study, men from northern Europe had higher levels of 8oxodG than those from southern Europe, supporting the idea that olive oil had a reductive effect.

I've started eating more olives and olive oil. The olive oil is displacing canola oil. But we need a comparative study of the effects of olive oil and canola oil on urine 8oxodG. Ditto for fish oils.

The bigger story on olive oil has been the suspected heart benefit. A September 2006 paper published in the Annals of Internal Medicine found olive oil boosts heart healthy HDL cholesterol while lowering triglycerides and lowering oxidized LDL cholesterol.

Results: A linear increase in high-density lipoprotein (HDL) cholesterol levels was observed for low-, medium-, and high-polyphenol olive oil: mean change, 0.025 mmol/L (95% CI, 0.003 to 0.05 mmol/L), 0.032 mmol/L (CI, 0.005 to 0.05 mmol/L), and 0.045 mmol/L (CI, 0.02 to 0.06 mmol/L), respectively. Total cholesterol–HDL cholesterol ratio decreased linearly with the phenolic content of the olive oil. Triglyceride levels decreased by an average of 0.05 mmol/L for all olive oils. Oxidative stress markers decreased linearly with increasing phenolic content.

When you can lower heart disease and cancer risk with the same dietary practice that sounds like a winner to me.

By Randall Parker    2007 January 02 10:48 PM   Entry Permalink | Comments (4)
2006 December 17 Sunday
Low Fat Diet Lowers Breast Cancer Recurrence

Women treated for beast cancer who were put on lower fat diets had lower rates of breast cancer recurrence.

Rowan T. Chlebowski, M.D., Ph.D., of the Los Angeles Biomedical Research Institute at the Harbor-University of California, Los Angeles Medical Center in Torrance, Calif., and his colleagues set out to determine whether a low-fat diet could prolong relapse-free survival in women with early-stage breast cancer.

Between February 1994 and January 2001, 2,437 women who had been treated for early-stage breast cancer were recruited from the Women’s Intervention Nutrition Study (WINS). They were randomly assigned to a dietary intervention group (40%), or a control group (60%).

...

At the beginning of the study, both groups consumed similar amounts of calories from fat—56 to 57 grams of fat per day (about 30% of total calories). After 1 year, the women in the dietary intervention group were consuming an average of 33 g/day (20.3% of total calories) compared with 51 g/day (29.2% of total calories) in the control group. The difference between the two groups was maintained throughout the trial. Average body weight was similar before the trial started, but 5 years later, the women in the intervention group weighed an average of 6 pounds less than the women in the control group.

So the women in the intervention group ate less food total and less calories total. How much of their reduction in fats consumed came as a reduction in animal fats?

The odds of recurrence of breast cancer was low in both groups because they were caught at an early stage.

Ninety-six of 975 women (9.8%) in the intervention group had some form of relapse, compared with 181 of 1462 women (12.4%) in the control group. The researchers calculate that 38 women would need to adopt such a dietary fat reduction plan to prevent one breast cancer recurrence. "Women in the dietary intervention group had a 24% lower risk of relapse than those in the control group," the authors write.

Their data also suggest that women with hormone receptor–negative breast cancers may have had the most benefit from the dietary fat reduction, but those results weren’t statistically significant and will require further confirmation. The authors plan to address these and other questions in ongoing follow-up studies of the women.

The reduction in calories consumed might have been the real cause of the difference. Or maybe something else about the difference in diets caused the difference in risks.

They caution that the study relied on self-reports of dietary fat intake. Also, the reduction in body weight in the dietary intervention group may have had an effect on breast cancer recurrence, rather than dietary fat intake on its own.

What I'd like to know: Is the risk reduction due to lower total calories consumed? Or perhaps due to a reduction in saturated fats? In other words, do all fats put women at equal risk of recurrence or perhaps does a particular saturated fat increarse the risk of recurrence? Or did the reduction of fatty foods in the diet increase the consumption of vegetables and fruits that have compounds that reduce breast cancer recurrence?

A diet that reduces the amount of fat in it also reduces and increases the amounts of many other things. Therefore even if the women on the lower fat diet had a real reduction in their risk of recurrence of breast cancer that does not begin to tell us why.

If the women on the lower fat diets ate more vegetables then compounds in the vegetables might have reduced the rate of breast cancer recurrence. Compounds in cruciferous vegetables called isothiocyanates (ITCs) have anti-cancer effects.

"The contribution of diet and nutrition to cancer risk, prevention and treatment have been a major focus of research in recent years because certain nutrients in vegetables and dietary agents appear to protect the body against diseases such as cancer," said Shivendra Singh, PhD, lead investigator and professor of pharmacology and urology at the University of Pittsburgh School of Medicine. "From epidemiologic data, we know that increased consumption of vegetables reduces the risk for certain types of cancer, but now we are beginning to understand the mechanisms by which certain edible vegetables like broccoli help our bodies fight cancer and other diseases."

Dr. Singh's study is based on phytochemicals found in several cruciferous vegetables called isothiocyanates (ITCs), which are generated when vegetables are either cut or chewed. His laboratory has found that phenethyl-ITC, or PEITC, is highly effective in suppressing the growth of human prostate cancer cells at concentrations achievable through dietary intake of cruciferous vegetables.

In seeking to further define the mechanisms by which PEITC induces apoptosis, or programmed cell death, mice were grafted with human prostate tumors and orally administered a small amount of PEITC daily. After 31 days of treatment, the average tumor volume in the control group that did not receive PEITC was 1.9 times higher than that of the treatment group. In addition, a pro-apoptotic protein called Bax appeared to play a role in bringing about apoptosis by PEITC.

While digging for the information to write this post I felt compelled to make and eat a big bowl of cole slaw made with non-fat mayo and some canola oil. An analogue of cruciferous vegetable compound sulfurophane also has anti-cancer effects.

It is pretty easy to make a scientifically informed argument for eating a lot more fruits and vegetables. In particular, for reduction of cancer risk cruciferous vegetables such as kale, broccoli, cabbage, and arugula have compounds in them that have anti-cancer properties. The relative value of fat avoidance is harder to discern. The various fatty acids vary considerably in their metabolic roles and the generally bad reputation given to fat is too broad. Most people need more omega 3 fatty acids, not less. Also, it is not clear to me that a diet high in monounsaturated fats is a net harm.

By Randall Parker    2006 December 17 01:26 PM   Entry Permalink | Comments (3)
2006 December 10 Sunday
High Protein Diet Ups Cancer Risk?

Should we eat less protein to increase our odds of living long lives?

Dec. 7, 2006 -- A great deal of research connects nutrition with cancer risk. Overweight people are at higher risk of developing post-menopausal breast cancer, endometrial cancer, colon cancer, kidney cancer and a certain type of esophageal cancer. Now preliminary findings from researchers at Washington University School of Medicine in St. Louis suggest that eating less protein may help protect against certain cancers that are not directly associated with obesity.

The research, published in the December issue of the American Journal of Clinical Nutrition, shows that lean people on a long-term, low-protein, low-calorie diet or participating in regular endurance exercise training have lower levels of plasma growth factors and certain hormones linked to cancer risk.

These researchers think that just because people on low calorie low protein diets have lower blood levels of insulin-like growth factor 1 (IGF-1) that this is proof that protein is a culprit for raising IGF-1.

"However, people on a low-protein, low-calorie diet had considerably lower levels of a particular plasma growth factor called IGF-1 than equally lean endurance runners," says the study's first author Luigi Fontana, M.D., Ph.D., assistant professor of medicine at Washington University and an investigator at the Istituto Superiore di Sanità in Rome, Italy. "That suggests to us that a diet lower in protein may have a greater protective effect against cancer than endurance exercise, independently of body fat mass."

But has Fontana looked hard at the body of research on calorie restriction? Are distance runners really a good gold standard to compare to? We already know that calorie restriction will boost longevity of lab mice as compared to mice who eat more and get more exercise.

Note that Fontana's group that had the lowest IGF-1 levels also ate a raw food vegetarian diet. Okay, that's lower in glycemic index, plus comes with lots of beneficial compounds in fruits and vegetables. Seems to be he changed too many variables at once between groups.

The study involved three groups of people. The first ate a low-protein, low-calorie, raw food vegetarian diet and was made up of 21 lean men and women. Another group consisted of 21 lean subjects who did regular endurance running, averaging about 48 miles per week. The runners ate a standard Western diet, consuming more calories and protein than group one. The third group included 21 sedentary people who also consumed a standard Western diet, higher in sugars, processed refined grains and animal products. The subjects were matched for age, sex and other demographic factors, and no one smoked or had diabetes, cardiovascular disease, cancer, lung disease or other chronic illness.

Protein intake was, not surprisingly, lowest in the low-protein group. They averaged a daily intake of 0.73 grams of protein per kilogram of body weight. Endurance runners ate 1.6 grams and sedentary people on the Western diet, 1.23 grams. The recommended daily allowance for protein intake is 0.8 grams. That's about three ounces of protein per day for a 220-pound man.

"It's interesting to us that both the runners and especially the sedentary people consumed about 50 percent more protein than recommended," says Fontana. "We know that if we consume 50 percent more calories than recommended, we will become obese. But there is not a lot of research on whether chronic over-consumption of protein also has harmful effects."

The conclusions these researchers draw about about protein and cancer risk are based on a known association between insulin-like growth factor 1 (IGF-1) blood plasma levels and risk of breast cancer, prostate cancer, and colon cancer.

Fontana and colleagues found significantly lower blood levels of plasma insulin-like growth factor 1 (IGF-1) in the low-protein diet group than in either the equally lean runners or the sedentary people eating a standard Western diet. Past research has linked pre-menopausal breast cancer, prostate cancer and certain types of colon cancer to high levels of IGF-1, a powerful growth factor that promotes cell proliferation. Data from animal studies also suggest that lower IGF-1 levels are associated with maximal lifespan.

What I'd like to see: A larger assortment of diets compared for effects upon blood IGF-1 levels. I do not believe they've proven their main claim against protein:

"Our findings show that in normal weight people IGF-1 levels are related to protein intake, independent of body weight and fat mass," Fontana says. "I believe our findings suggest that protein intake may be very important in regulating cancer risk."

See below for why I doubt the strength of their claim. They might be right. I'd really like to know whether they are right. But the study strikes me as having a major shortcoming.

He calls the study a hypothesis-generating paper that suggests connections between dietary protein and epidemiological studies that show associations between IGF-1 levels and the risk of cancer. But he says more research is needed to clarify what that connection is.

I see a big obvious shortcoming of this study in this paragraph. Do you see it too?

The researchers also found that the group of endurance runners in the study consumed the highest number of calories, averaging more than 2,600 per day. Those on a standard Western diet consumed just over 2,300 calories daily, while those in the low-calorie, low-protein group ate just under 2,000 calories a day. Members of the latter group also tended to weigh less than sedentary people but slightly more than the endurance runners. The average body mass index (BMI) in the low-protein, low-calorie group was 21.3. BMI averaged 21.1 among the runners and 26.5 among those who were sedentary. BMI is a measurement of weight divided by height squared. People with a BMI greater than 25 are considered overweight.

Problem: The people on the standard diet ate more calories than those on the low protein diet. So how much of the lower blood IGF-1 is due to lower calories rather than lower protein? We already know that calorie restriction causes all sorts of blood markers to shift in directions favorable to good health. Cholesterol and triglycerides go down. Markers for insulin sensitivity improve. So I would expect better IGF-1 just from the lower calorie intake.

Note that their lower calorie lower protein study participants had mower body mass indexes. Was the lower IGF-1 just due to that? Have any studies been done comparing IGF-1 levels as a function of BMI?

Are any readers aware of studies of people on the high protein Atkins diet that looked at blood IGF-1 levels?

What is needed: Comparison of IGF-1 levels of people on different ratios of fats, carbohydrates, and protein on a normal calorie diet. Then, repeat the same experiment on people who are on calorie restriction diets. I certainly expect the people on lower calorie diets to have lower IGF-1. But will there be differences in IGF-1 based on the relative contributions of protein, fat, and carbos as calorie sources?

While I'm asking for experiments: I'd like to see comparisons of IGF-1 for diets where the carbos come from different sources such as low glycemic index versus high glycemic index foods and high fructose versus high glucose foods.

I'd also like to see the effect of BMI on IGF-1. Will high BMI people have high IGF-1 even if, say, they go on a low protein diet. I'd expect they would. Can any sort of diet that does not bring off weight lower IGF-1? Does high dose resveratrol lower IGF-1?

Can anyone point out studies in the research literature that control for factors that Fontana's team apparently didn't separately control for?

Update: The abstract provides more details:

Plasma concentrations of insulin, free sex hormones, leptin, and C-reactive protein were lower and sex hormone–binding globulin was higher in the low-protein, low-calorie diet and runner groups than in the sedentary Western diet group (all P < 0.05). Plasma insulin-like growth factor I (IGF-I) and the concentration ratio of IGF-I to IGF binding protein 3 were lower in the low-protein, low-calorie diet group (139 ± 37 ng/mL and 0.033 ± 0.01, respectively) than in the runner (177 ± 37 ng/mL and 0.044 ± 0.01, respectively) and sedentary Western (201 ± 42 ng/mL and 0.046 ± 0.01, respectively) diet groups (P < 0.005).

But, again, how much of the result was due to A) lower protein, B) lower calories, or C) lower BMI? The latter two will both lower IGF-1 and markers for inflammation such as C-reactive protein. See the comments for pointers to other research that suggests, yes, protein restriction can lower unfavorable indicators in blood such as reactive oxygen species (ROS). So maybe a lower protein diet will help.

By Randall Parker    2006 December 10 09:12 AM   Entry Permalink | Comments (6)
2006 October 21 Saturday
High Glycemic Index Diet Kidney Cancer Risk?

A retrospective study finds an association between higher glycemic index foods and kidney cancer.

Comparing the highest with the lowest quintile of intake, consumption of bread, pasta and rice, and milk and yogurt increased the risk of RCC by 94%, 29%, and 27%, respectively.

Conversely, intake of poultry, processed meat, and vegetable appeared to reduce the risk by 26%, 36%, and 35%, respectively.

Other foods such as fruits, red meats, cheese, potatoes, eggs, and fish had no effect.

The study collected information about past dietary habits - and studies of this sort suffer from faulty memories of interviewees.

The researchers included Francesca Bravi, MD, of the Istituto di Ricerche Farmacologiche "Mario Negri" in Milan.

Between 1992 and 2004, Bravi's team interviewed 767 patients with renal cell carcinoma at Italian hospitals. They also interviewed 1,534 patients without kidney cancer.

Patients completed surveys about their diets during the previous two years. The questions covered 78 foods and beverages.

A diet of high glycemic index foods might increase the risk of cancer by elevating insulin-like growth factor hormones such as IGF-1 and IGF-2.

"As for other common cancers, the increased risk of renal cell carcinoma for elevated cereals intake may be due to the high glycemic index of these foods, and their possible involvement in insulin-like growth factors," the investigators wrote.

In lower level species such as nematodes knocking out an equivalent IGF gene increases life expectancy.

I would expect an ideal diet to lower IGF hormones, lower LDL cholesterol, boost HDL cholesterol, lower triglycerides, lower inflammation markers such as C Reactive Protein (CRP), and lower markers for oxidative stress. So what would such an ideal diet look like?

If high glycemic index foods cause higher kidney cancer risk then I'm surprised that potatoes do not show up as boosting kidney cancer risk. But David Mendosa's very useful Glycemic Index (GI) and Glycemic Load (GL) chart shows some potatoes have fairly low glycemic indexes. Though note the considerable measured variation (56 to 111) just among Russet potatoes. Do fresher potatoes have higher GI? Does boiling versus baking cause a difference in GI?

Note on rice: The glycemic index of rice varies in predictable ways. The sticky rice found in Chinese restaurants has a GI over 100. But a high 28% amylose rice tests at GI 27 and Basmati rice at 67 to 60. Uncle Ben's rice appears to vary in GI by country (different varieties sold in different places?) and different type (e.g. slower and faster cooking types). If a brand name rice seller such as Uncle Ben's would market a low GI rice I'd buy it. As things stand I'm eating Basmati and Uncle Ben's rices.

Update: Uncle Ben's converted rice has low glycemic index and in 3 experiments done in the US and Canada ranges from 38 to 50. So that's probably the most readily available low glycemic index rice in the US and Canada.

Update II: I am also surprised that pasta consumption has a positive association with kidney cancer risk. The type of wheat used to make pasta has a much lower glycemic index than the type of wheat used to make bread. Most of the pastas have glycemic indexes below 50. But even lower glycemic index foods that are carbohydrate-based do break down in the intestines and feed into the bloodstream. So eat enough and you'll get a sugar surge.

By Randall Parker    2006 October 21 12:41 PM   Entry Permalink | Comments (1)
2006 October 18 Wednesday
More Evidence Vitamin D Reduces Breast Cancer Risk

Women with less advanced breast cancer have more vitamin D in their blood than women with more advanced breast cancer.

Vitamin D may help curb breast cancer progression, suggests a small study published ahead of print in the Journal of Clinical Pathology.

The authors reach their conclusion from a study of 279 women with invasive breast cancer. The disease was in the early stages in 204 women, and advanced in the remainder.

Serum levels of vitamin D, parathyroid hormone, and calcium were measured in both groups of women.

The results showed that women with early stage disease had significantly higher levels of vitamin D and significantly lower levels of parathyroid hormone than did the women with advanced disease.

There was little difference in calcium levels between the two groups.

The authors say that the exact reasons for the disparity are unclear, nor is it known whether the low levels of vitamin D among those with advanced disease are a cause or consequence of the cancer itself.

But it is known that vitamin D treatment boosts the activity of certain key genes and dampens it down in others. One gene that is boosted is p21, which has an important role in controlling the cell cycle.

Does the advance of the cancer lower vitamin D? Or does the higher vitamin D cause cancer to develop more slowly so that people who have higher blood vitamin D tend to stay in early stage cancer longer and have a higher chance of getting diagnosed while still in earlier stages? My guess is the latter factor is at work because so much other research has demonstrated anti-cancer effects of vitamin D.

From the body of the full research paper:

This study has shown that serum levels of 25(OH)D were markedly higher and that PTH levels were considerably lower in patients with early-stage breast cancer than in those with locally advanced or metastatic disease. The notably higher serum PTH in patients with metastatic disease than that in those with early-stage disease is presumably due to the lower vitamin D level, resulting in a lower serum calcium and therefore a rise in serum PTH. The raised PTH level can therefore account for the lack of any difference in serum calcium between these two groups. Epidemiological studies have previously shown that maintenance of adequate levels of vitamin D via exposure to sunlight is associated with a reduced incidence and mortality of breast cancer.

Also see my previous posts: Vitamin D Could Decrease Overall Cancer Risk 30% and Vitamin D Reduces Breast Cancer Risk and Vitamin D Reduces Risk Of Pancreatic Cancer and Fatty Fish In Diet Lower Kidney Cancer Risk.

By Randall Parker    2006 October 18 09:06 PM   Entry Permalink | Comments (1)
2006 September 23 Saturday
Fatty Fish In Diet Lower Kidney Cancer Risk

A new study out in the Journal of the American Medical Association provides more reason to eat fatty fish. Vitamin D and/or omega 3 fatty acids are probably involved in the protective effect of eating fatty fish.

Preliminary research suggests that higher consumption of fatty fish in women is linked with a lower risk of renal cell carcinoma, a common form of kidney cancer, according to a study in the September 20 issue of JAMA.

Renal cell carcinoma (RCC) involving the renal parenchyma (the functional tissue of the kidney) accounts for more than 80 percent of all kidney cancers. Renal cell carcinoma incidence rates in the United States had been increasing in 1970-1990s, especially among black women and men; more recent data suggest a leveling off in this trend for most racial groups. The evidence that fish consumption, especially fatty fish, may be associated with lower risk of several cancers has not been consistent, according to background information in the article.

By differentiating between consumption of fish with differing levels of omega 3 fatty acids the researchers were able to discover a stronger relationship between fish consumption and reduced cancer risk.

Previous studies have analyzed total fish consumption and have not taken into account that there are large differences between fatty fish and lean fish in the content of omega-3 fatty acids and vitamin D. Marine omega-3 polyunsaturated fatty acids, eicosapentaenoic acid and docosahexaneoic acid, which are present in significant amounts in fatty cold-water fish (up to 20-30 times higher content than in lean fish), have been reported to slow the development of cancer. Fatty fish has 3 to 5 times higher content of vitamin D than lean fish, and lower serum vitamin D levels have been associated with development and progression of RCC.

Alicja Wolk, D.M.Sc., of the Karolinska Institutet, Stockholm, Sweden and colleagues investigated the association between fatty fish and lean fish consumption and the risk for development of RCC in a population with a relatively high consumption of fatty fish. The participants, from the Swedish Mammography Cohort, included 61,433 women age 40 to 76 years without previous diagnosis of cancer at baseline (March 1987 to December 1990). Participants filled in a food frequency questionnaire at baseline and in September 1997. The researchers considered fatty fish to include salmon, herring, sardines, and mackerel; lean fish included cod, tuna, and sweet water fish; and other seafood included shrimp, lobster, and crayfish.

During an average of 15.3 years of follow-up between 1987 and 2004, 150 RCC cases were diagnosed. After adjustment for potential confounders, an inverse association of fatty fish consumption with the risk of RCC was found, while no association was found with the consumption of lean fish or other seafood.

Want to cut your kidney cancer risk by about 3/4ths?

“In this large population-based cohort with data on long-term diet, we found that women who consumed one or more servings of fatty fish per week had a statistically significant 44 percent decreased risk of RCC compared with women who did not consume any fish. Women who reported consistent long-term consumption of fatty fish at baseline and 10 years later had a statistically significant 74 percent lower risk,” the authors write.

Our results support the hypothesis that frequent consumption of fatty fish may lower the risk of RCC possibly due to increased intake of fish oil rich in eicosapentaenoic acid and docosahexaneoic acid as well as vitamin D,” they write. “Our results, however, require confirmation because this is the first epidemiological study addressing this issue.” (JAMA. 2006;296:1371-1376)

The reducting in kidney cancer risk is probably also being accompanied by a reduction in risk of other types of cancer. The vitamin D in the fish has already been linked to reduction of risk for other cancers. See my posts Vitamin D Could Decrease Overall Cancer Risk 30%, Vitamin D Reduces Risk Of Pancreatic Cancer, and Vitamin D Reduces Breast Cancer Risk. Also, omega 3 fatty acids as contributors to reduced kidney cancer risk seem quite plausible. See my post Omega 3 Fatty Acids Cut Rat Prostate Cancer.

I'm having salmon for dinner.

By Randall Parker    2006 September 23 09:43 AM   Entry Permalink | Comments (0)
2006 September 11 Monday
Vitamin D Reduces Risk Of Pancreatic Cancer

Yet more evidence that vitamin D reduces the risk of cancer.

PHILADELPHIA -- Consumption of Vitamin D tablets was found to cut the risk of pancreatic cancer nearly in half, according to a study led by researchers at Northwestern and Harvard universities.

The findings point to Vitamin D's potential to prevent the disease, and is one of the first known studies to use a large-scale epidemiological survey to examine the relationship between the nutrient and cancer of the pancreas. The study, led by Halcyon Skinner, Ph.D., of Northwestern, appears in the September issue of Cancer Epidemiology Biomarkers & Prevention.

The study examined data from two large, long-term health surveys and found that taking the U.S. Recommended Daily Allowance of Vitamin D (400 IU/day) reduced the risk of pancreatic cancer by 43 percent. By comparison, those who consumed less than 150 IUs per day experienced a 22 percent reduced risk of cancer. Increased consumption of the vitamin beyond 400 IUs per day resulted in no significant increased benefit.

The conclusions were reached by analysis of two prospective studies.

Skinner, currently in the Department of Population Health Sciences at the University of Wisconsin School of Medicine and Public Health, and his colleagues analyzed data from two long-term studies of health and diet practices, conducted at Harvard University. They looked at data on 46,771 men aged 40 to 75 years who took part in the Health Professionals Follow-up Study, and 75,427 women aged 38 to 65 years who participated in the Nurses' Health Study. Between the two studies, they identified 365 cases of pancreatic cancer. The surveys are considered valuable for their prospective design, following health trends instead of looking at purely historical information, high follow-up rates and the ability to enable researchers like Skinner to incorporate data from two independent studies.

If you get pancreatic cancer you die.

Pancreatic cancer is a rapidly fatal disease and the fourth-leading cause of death from cancer in the United States. This year, the American Cancer Society estimates that 32,000 new cases of cancer will be diagnosed. About the same number of people will die this year from the disease. It has no known cure, and surgical treatments are not often effective. Except for cigarette smoking, no environmental factors or dietary practices have been linked to the disease.

Vitamin D is probably the best supplement to take to reduce the risk of a wide range of cancers.

Also see my posts Vitamin D Could Decrease Overall Cancer Risk 30%, Vitamin D Reduces Breast Cancer Risk, and Higher Vitamin D Reduces Aging Bone Fracture Risks.

By Randall Parker    2006 September 11 11:35 PM   Entry Permalink | Comments (7)
2006 August 27 Sunday
Diet Change Slows Prostate Cancer

Yet another reason to eat a better diet and avoid stress-inducing environments.

One out of six American men will develop prostate cancer at some point in their life, and more than a third of them will experience a recurrence after undergoing treatment, putting them at high risk to die of the disease. New research from the Moores Cancer Center and School of Medicine at University of California, San Diego suggests that diet changes, reinforced by stress management training, may be effective in slowing or halting the spread of the this deadly cancer.

The 6-month study, published in the September issue of Integrative Cancer Therapies, focused on the change in the levels of prostate-specific antigen (PSA), an indicator of the cancer, in response to a plant-based diet and stress reduction. Patients were taught to increase consumption of plant-based foods such as whole grains, cruciferous and leafy green vegetables, beans and legumes, and fruit, and to decrease the intake of meat, dairy products and refined carbohydrates. They were also provided with stress management training, which included meditation, yoga and t’ai chi exercises.

Aside: Does anyone know of reliable research using stress markers such as blood cortisol to compare the effectiveness of various stress management techniques?

The plant-based diet and stress reduction intervention was effective in significantly reducing the PSA rate, indicating a reduction in the rate of progression of the prostate cancer. Ten patients with recurrent, invasive prostate cancer completed the pilot clinical trial. Rates of PSA rise were determined for each patient from the time of disease recurrence following treatment up to the start of the study (pre-study), and from the time immediately preceding the study intervention to the end of the intervention (0-6 months).

By the end of the intervention, four of 10 patients experienced an absolute reduction in their PSA levels, and nine of 10 experienced a decrease in the rate of further PSA rise. The median time it took for the men’s PSA levels to double increased from 11.9 months at pre-study to 112.3 months (intervention).

That's a dramatic change for people who already have prostate cancer. I'd like to see this broken down in a more detailed study that just diet changes and stress reduction separately. I'd also like to see various diet changes compared. Would a diet that drastically improved blood lipid profiles provide most of the benefit? Reduce triglycerides and LDL cholesterol and raise HDL cholesterol to lower your PSA?

By Randall Parker    2006 August 27 09:41 AM   Entry Permalink | Comments (3)
2006 August 01 Tuesday
Curcumin And Quercetin Cut Intestine Cancer Risk

Curcumin And Quercetin Reduce Precancerous Lesions In in the lower bowel part of intestines.

A small but informative clinical trial by Johns Hopkins investigators shows that a pill combining chemicals found in turmeric, a spice used in curries, and onions reduces both the size and number of precancerous lesions in the human intestinal tract.

In the study, published in the August issue of Clinical Gastroenterology and Hepatology, five patients with an inherited form of precancerous polyps in the lower bowel known as familial adenomatous polyposis (FAP) were treated with regular doses of curcumin (the chemical found in turmeric) and quercetin, an antioxidant in onions, over an average of six months. The average number of polyps dropped 60.4 percent, and the average size dropped by 50.9 percent, according to a team led by Francis M. Giardiello, M.D., at the Division of Gastroenterology, The Johns Hopkins University School of Medicine, and Marcia Cruz-Correa, M.D., Ph.D., at Johns Hopkins and the University of Puerto Rico School of Medicine.

"We believe this is the first proof of principle that these substances have significant effects in patients with FAP," says Giardiello.

Dietary ways to delay the development of cancer might save your life. Various cancers will become curable some time in the next 20 years. It would be so totally unfun to die the year before a cure to your future cancer. Dietary changes that reduce your cancer risks, even if they just delay the development of cancer, could save your life.

The curcumin dose used is much larger than that found in turmeric in Indian food.

Previous observational studies in populations that consume large amounts of curry, as well as laboratory research on rodents have strongly suggested that curcumin -- a relatively innocuous yellow pigment extracted from turmeric, the powdered root of the herb curcuma longa and one of the main ingredients in Asian curries -- might be effective in preventing and/or treating cancer in the lower intestine, according to Cruz-Correa. She said curcumin has been given to cancer patients, and previous studies have demonstrated that is well tolerated at high doses.

Similarly, quercetin -- a member of a group of plant-derived polyphenolic anti-oxidant substances known as flavanoids (found in a variety of foods including onions, green tea and red wine) -- has been shown to inhibit growth of colon cancer cell lines in humans and abnormal colorectal cells in rodents.

Although these substances were administered together, due to relative dose levels it is Giardiello's belief that curcumin is the key agent.

"The amount of quercetin we administered was similar to what many people consume daily; however, the amount of curcumin is many times what a person might ingest in a typical diet, since turmeric only contains on average 3 percent to 5 percent curcumin by weight," says Giardiello. Because of this, he cautions that simply consuming curry and onions may not have the same effect as was produced in this study.

Curcumin capsules would be easier than eating turmeric on everything.

Red onions have the most quercetin but scientists are trying to develop even higher quercetin onions.

For the most quercetin, eat red and yellow onions; white onions have very little. Coming soon: super-potent onions. At the University of Wisconsin and the University of Texas M.D. Anderson Cancer Center, researchers are developing onions extra-high in quercetin and other disease-fighting phytochemicals. Red wine, broccoli and tea are also rich in quercetin.

Apples have it too. "An apple a day...". Eventually we'll get foods genetically engineered to contain all the best cancer risk reducers. In the meantime, if you want to boost topical absorption of quercetin 1000 times ultrasound with quercetin will dramatically boost quercetin absorption.

By Randall Parker    2006 August 01 07:00 PM   Entry Permalink | Comments (3)
Omega 3 Fatty Acids Cut Rat Prostate Cancer

Another reason why I'll eat salmon tonight:

Scientists used a special mouse model for hormone-sensitive prostate cancer that closely mirrors the disease in humans. Researchers fed one group of mice a diet comprised of 20 percent fat with a healthy one-to-one ratio of omega-6 to omega-3 fatty acids. A second group of mice were fed the same diet but with the fat derived from mostly omega-6 fatty acids.

The study showed that tumor cell growth rates decreased by 22 percent and PSA levels were 77 percent lower in the group receiving a healthier balance of fatty acids compared with the group that received predominantly omega-6 fatty acids.

The most likely mechanism for the tumor reductions, according to researchers, was due to an increase of the prostate tumor omega-3 fatty acids DHA and EPA and a lowering of the omega-6 acid known as arachidonic acid. These three fatty acids compete to be converted by cyclooxgenase enzymes (COX-1 and COX-2) into prostaglandins, which can become either pro-inflammatory and increase tumor growth, or anti-inflammatory and reduce growth.

Researchers found that pro-inflammatory prostaglandin (PGE-2) levels were 83 percent lower in tumors in the omega-3 group than in mice on the predominantly omega-6 fatty acid diet, demonstrating that higher levels of DHA and EPA may lead to development of more anti-inflammatory prostaglandins.

"This is one of the first studies showing changes in diet can impact the inflammatory response that may play a role in prostate cancer tumor growth," Aronson said. "We may be able to use EPA and DHA supplements while also reducing omega-6 fatty acids in the diet as a cancer prevention tool or possibly to reduce progression in men with prostate cancer."

The fish in the oceans are getting exhausted and fish costs more than cheaper land-based meat sources. We need genetically engineered crops that make more omega 3 fatty acids.

Monsanto might have genetically engineered high omega 3 fatty acid soybeans on the market in 5 or so years.

Monsanto has grown high-yielding, Omega-3-enriched soybeans, extracted the oil and shown that it has a pleasant taste and no fish odor that might turn off food companies and consumers, said Robb Fraley, chief technology officer. If the oil proves to be stable enough for use in processed foods, which must sit on store shelves without spoiling, and gains regulatory approval, he sees it appearing some time after 2010 in salad dressings, soy milks, margarines, yogurts and other foods.

"We have a lot of excitement about this," he said. "We now can open the door to a whole new way of delivering Omega-3s in the diet through food" rather than supplements in pill form.

Look for the Monsanto high omega 3 soy in 2011 or 2012.

Vistive Omega-3 is another modification in the pipeline, due to become available around 2011-2012. According to the company, the “enhanced oils represent an environmentally sustainable, economical source of Omega-3s, providing consumers with new options for omega-rich foods.”

Dupont is also hot on the trail of high omega 3 soy beans.

DuPont, one of the major movers and shakers in this area, revealed last week that it has developed a transgenic soybean with a long-chain omega-3 content of 40 per cent, and is heading for field testing of the crop.

DuPont's focus has been on maximising both EPA and DHA, and scientists based at the DuPont Experimental Station in Delaware, have expanded the standard procedure of desaturating and elongating the shorter chain fatty acids by using co-expression of an additional enzyme, omega-3 microsomal desaturase from the fungus Saprolegnia diclina, to convert the omega-6 very long chain polyunsaturated fatty acids (VLC-PUFAs) to omega-3s.

The previous article says BASF is also putting a big effort into development of high omega 3 crops.

High omega 3 soy will bring all sorts of benefits. See my posts Fish Consumption By Mom Makes Babies Smarter? and Fish In Diet Slows Rate Of Cognitive Decline for examples.

By Randall Parker    2006 August 01 06:23 PM   Entry Permalink | Comments (6)
2006 July 05 Wednesday
Pomegranate Slows Prostate Cancer

Drink pomegranate juice.

Drinking an eight ounce glass of pomegranate juice daily increased by nearly four times the period during which PSA levels in men treated for prostate cancer remained stable, a three-year UCLA study has found.

The study involved 50 men who had undergone surgery or radiation but quickly experienced increases in prostate-specific antigen or PSA, a biomarker that indicates the presence of cancer. UCLA researchers measured "doubling time," how long it takes for PSA levels to double, a signal that the cancer is progressing, said Dr. Allan Pantuck, an associate professor of urology, a Jonsson Cancer Center researcher and lead author of the study.

Doubling time is crucial in prostate cancer, Pantuck said, because patients who have short doubling times are more likely to die from their cancer. The average doubling time is about 15 months. In the UCLA study, Pantuck and his team observed increases in doubling times from 15 months to 54 months, an almost four-fold increase.

"That's a big increase. I was surprised when I saw such an improvement in PSA numbers," Pantuck said. "In older men 65 to 70 who have been treated for prostate cancer, we can give them pomegranate juice and it may be possible for them to outlive their risk of dying from their cancer. We're hoping we may be able to prevent or delay the need for other therapies usually used in this population such as hormone treatment or chemotherapy, both of which bring with them harmful side effects."

That's a huge increase in doubling times. If you get diagnosed with prostate cancer now and pomegranate juice extends your life by several years then you might live long enough for a cure to be developed.

Pomegranate juice contains all sorts of good things.

Pomegranate juice is known to have anti-inflammatory effects and high levels of anti-oxidants, which are believed to protect the body from free-radical damage. It also contains poly-phenols, natural antioxidant compounds found in green tea, as well as isoflavones commonly found in soy, and ellagic acid, which is believed to play a role in cancer cell death.

"There are many substances in pomegranate juice that may be prompting this response," Pantuck said. "We don't know if it's one magic bullet or the combination of everything we know is in this juice. My guess is that it's probably a combination of elements, rather than a single component."

Some of the men have kept their PSA levels from rising for 3 years with pomegranate.

Pantuck said he has men on the study more than three years out who are not being treated for prostate cancer other than drinking pomegranate juice and their PSA levels continue to be suppressed.

"The juice seems to be working," he said.

Some of you ladies might be thinking that pomegranate against cancer is just a guy thing. Not so. Back in 2001 an Israeli team found evidence of pomegranate against breast cancer.

The Technion-Israel Institute of Technology research team presented two studies at an international conference in June indicating that pomegranate seed oil triggers apoptosis -- a self-destruct mechanism in breast cancer cells. Furthermore, pomegranate juice can be toxic to most estrogen-dependent breast cancer cells, while leaving normal breast cells largely unaffected. Estrogen is a hormone often prescribed to protect postmenopausal women against heart disease and osteoporosis.

In the first study, laboratory-grown breast cancer cells were treated for three days with pomegranate seed oil. The researchers observed apoptosis in 37 to 56 percent of the cancer cells, depending upon the dose of oil applied.

In the second study, both normal and cancerous breast cells were exposed to fermented pomegranate juice (pomegranate wine) and pomegranate peel extracts, which contain polyphenols (powerful antioxidants). The vast majority of the normal cells remained unaffected by the two pomegranate derivatives. But more than 75 percent of the estrogen-dependent cancer cells, and approximately half of the non-estrogen dependent cancer cells were destroyed by exposure to these same pomegranate products.

"Pomegranates are unique in that the hormonal combinations inherent in the fruit seem to be helpful both for the prevention and treatment of breast cancer," explains Dr. Ephraim Lansky, who headed the studies. "Pomegranates seem to replace needed estrogen often prescribed to protect postmenopausal women against heart disease and osteoporosis, while selectively destroying estrogen-dependent cancer cells."

Pomegranate might also reduce the odds of getting skin cancer. Still other scientists are using liquid chromatography to isolate components in pomegranate with the strongest anti-cancer effects.

By Randall Parker    2006 July 05 08:22 PM   Entry Permalink | Comments (2)
2006 April 05 Wednesday
Vitamin D Reduces Breast Cancer Risk

Papers presented at the 97th Annual Meeting of the American Association for Cancer Research provide additional evidence that higher vitamin D reduces breast cancer risk.

Now, new studies by researchers at the Samuel Lunenfeld Research Institute at Mount Sinai Hospital in Toronto suggest the "sunshine" vitamin may play a significant role in reducing breast cancer risk. The results, based on population data, found the reduction was most apparent among subjects exposed to the highest levels of vitamin D when they were young.

By interviewing about 576 patients who had been diagnosed with breast cancer and 1,135 people who had no cancer, the scientists discovered that significant reductions in breast cancer were found in those who had either worked in an outdoor job, had taken part in outdoor activities when young, or consumed cod liver oil or milk.

Working an outdoor job between ages 10 to19 resulted in an estimated 40 percent reduced risk of breast cancer, while frequent outdoor activities between ages 10 to 29 lowered breast cancer risk by an estimated 35 percent.

"These outdoor activities included those that didn't involve physical activity," said Julie Knight, who headed the Mount Sinai research team. "And so we believe that this is evidence of a reduction of breast cancer risk, associated with earlier exposure to the sun."

For dietary influences on cancer development, taking cod liver oil between ages 10 to 19 reduced breast cancer risk by about 25 percent, and consuming at least nine glasses of milk every week between the ages of 10 to 29 reduced the risk by 35 percent. The dietary and lifestyle reductions were significant, even when adjusted for other risk factors for breast cancer such as age, ethnicity, close relatives with breast cancer, age at menarche and age at a woman's first birth.

Women with higher concentrations of vitamin D in the blood are at less risk of breast cancer.

Increasing doses of dietary Vitamin D may help prevent breast cancer, with the optimal level of intake of Vitamin D more that three times the current average for Americans, according to a study conducted at the University of California, San Diego.

Previous studies have suggested a link between Vitamin D deficiency and higher incidence of breast cancer. Cedric Garland, Dr. P.H., and Edward Gorham, Ph.D., of UCSD, and their colleagues examined existing cancer studies to determine if higher Vitamin D levels in the blood could reduce the risk of cancer.

"There is a strong inverse dose-response relationship between the serum concentration of 25-hydroxyvitamin D and the risk of breast cancer," Garland said. "It's a close fit to a linear model," meaning that higher amounts of 25-hydroxyvitamin D in the serum resulted in decreased risk of breast cancer. The evidence further pointed to a level of Vitamin D measured in blood that correlated with a 50 percent reduction in the incidence of breast cancer.

Garland, Gorham and their colleagues studied a serum Vitamin D metabolite known as 25 hydroxyvitamin D and its association with breast cancer occurrence in a pooled study that included 1,760 women. The studies that provided the data for the pooled analysis were conducted by Elizabeth R. Bertone-Johnson and colleagues at Harvard, and L.C. Lowe and associates at Saint George's Hospital Medical School in London.

According to the pooled analysis, Vitamin D in blood serum equal to 52 nanograms per milliliter was associated with a 50 percent reduced risk of breast cancer. To move closer to a serum concentration of 52 nanograms/milliliter, a typical individual would have to consume no less than 1,000 International Units (IU) of Vitamin D every day, through supplements or vitamin D-fortified foods. Currently, a typical American consumes only 320 International Units of Vitamin D a day. The upper limit for vitamin D intake established by the National Academy of Sciences is 2,400 IU/day, but no toxic effects of vitamin D intake have been reported for intakes below 3,800 IU per day.

I already take vitamin D pills that put me up in the safer range.

The linked page also reports evidence that flavonoids reduce the risk of breast and ovarian cancer. Click thru and read the whole thing.

Also see my posts Vitamin D Could Decrease Overall Cancer Risk 30% and Vitamin D Crucial For Long Term Lung Health.

By Randall Parker    2006 April 05 09:51 PM   Entry Permalink | Comments (3)
2005 December 17 Saturday
Dietary Fiber Does Not Lower Colorectal Cancer Risk

The role of dietary fiber as a preventive against colon cancer remains very unproven.

In an analysis combining data from 13 studies, high intake of dietary fiber was not associated with reduced risk of colorectal cancer, according to a study in the December 14 issue of JAMA.

Dietary fiber has been hypothesized to reduce the risk of colorectal cancer, according to background information in the article. However, the results of numerous epidemiological studies have been inconsistent. Ecological correlation studies and many case-control studies have found an inverse association between dietary fiber intake and risk of colorectal cancer. But most prospective cohort studies have found no association between dietary fiber intake and risk of colorectal cancer or adenomas (precursors of colorectal cancer), and randomized clinical trials of dietary fiber supplementation have failed to show reductions in the recurrence of colorectal adenomas.

Yikyung Park, Sc.D., formerly of the Harvard School of Public Health, Boston, and colleagues evaluated the association between dietary fiber intake and risk of colorectal cancer by reanalyzing the primary data from 13 prospective cohort studies (Pooling Project of Prospective Studies of Diet and Cancer). The pooled analysis included 725,628 men and women who were followed-up for 6 to 20 years across studies.

During the follow-up, 8,081 colorectal cancer cases were identified. Among the studies, median (midpoint) energy-adjusted dietary fiber intake ranged from 14 to 28 g/d in men and from 13 to 24 g/d in women. The major source of dietary fiber varied across studies with cereals as a major contributor to dietary fiber intake in the European studies, and fruits and vegetables as the main sources in the North American studies.

Note the factors here that influenced risk. These are the things you want to get more or less of to lower your risk.

In the age-adjusted model, dietary fiber intake was significantly associated with a 16 percent lower risk of colorectal cancer in the highest quintile compared with the lowest. This association was attenuated slightly but still remained statistically significant after adjusting for nondietary risk factors, multivitamin use, and total energy intake. Additional adjustment for dietary folate intake further weakened the association. In the final model, which further adjusted for other dietary factors, such as red meat, total milk, and alcohol intake, only a nonsignificant weak inverse association was found. Fiber intake from cereals, fruits, and vegetables was not associated with risk of colorectal cancer.

The factors that reduced the association between fiber and risk are the factors that probably really do reduce risk. So get less red meat and milk for example. Did alcohol intake reduce or increase the risk of colon cancer? Probably the fruits and vegetables decreased risk due to other compounds (notably vitamins, minerals, and anti-carcinogen compounds) and not due to fiber. The fiber just happened to always be there.

One theory on why fiber should lower colon cancer risk is that it dilutes toxins and speeds the passage of toxins through the intestinal tract. Maybe adjusting for red meat consumption factors out the value of eating the fiber. If a person does eat a lot of red meat then maybe fiber really does protect agianst toxins formed in the intestines from red meat. Though I'm speculating.

But consumption of whole plant food like vegetables that are high in dietary fiber is associated with lower risk of heart disease and diabetes. So you could eat high fiber fruits and vegetables anyway.

"The association between dietary fiber intake and risk of colorectal cancer has been inconsistent among observational studies and several factors may explain the disparity: potential biases in each study, the failure to adjust for covariates in the multivariate models, and the range of dietary fiber intake," the authors write.

"In conclusion, we did not find support for a linear inverse association between dietary fiber intake and risk of colorectal cancer in a pooled analysis of 13 prospective cohort studies. Although high dietary fiber intake may not have a major effect on the risk of colorectal cancer, a diet high in dietary fiber from whole plant foods can be advised because this has been related to lower risks of other chronic conditions such as heart disease and diabetes," the researchers write.

Just eating a high fiber food extract is probably a waste of time. But vegetables continue to be good for you. Most people (and myself) continue to not eat enough veggies.

By Randall Parker    2005 December 17 09:27 AM   Entry Permalink | Comments (4)
2005 October 28 Friday
Cruciferous Vegetables Lower Cancer Risk Only For Some With Inactive Genes

Eating cruciferous vegetables only helps lower the risk of cancer if you have inactive forms of glutathione-S-transferase enzymes.

Paul Brennan of the International Agency for Cancer Research and other scientists have just completed a lung-cancer study that appears to back up this theory. In particular, the team studied the diets and genes of more than 4,000 people in Eastern and Central Europe.

According to the results published today in the journal The Lancet, the researchers found that people with an inactive form of the GSTM1 gene were 33-per-cent less likely to get lung cancer if they ate cruciferous vegetables on a weekly basis.

Furthermore, "in people who had an inactive GSTT1, there was a 37-per-cent protective effect, while those with both genes inactivated had a 72-per-cent protective effect."

They found no protective effect in people with active forms of the genes.

Think about that last sentence. If you could get tested and discovered that you have active forms of both genes then you'd have no health reason to eat Brussels sprouts and broccoli. That strikes me as something I'd really like to know.

On the other hand, this result might also provide support for the idea of developing drugs to deactivate the glutathione-S-transferase enzymes so that isothiocyanates will hang around the body for longer periods of time. Or maybe high dose isothiocyanate pills could overwhelm the enzymes that break them down so that the isothiocyanates can still provide protection.

Over 4000 people were used in the study.

For this study, the researchers looked at 2,141 people with lung cancer, comparing them with 2,168 healthy individuals in the Czech Republic, Hungary, Poland, Slovakia, Romania and Russia, where consumption of these vegetables has traditionally been high.

Participants filled out a food questionnaire, and also gave a blood sample so researchers could detect GSTM1 and GSTT1.

The questionnaire listed 23 foods, including three cruciferous vegetables: cabbage and a combination of Brussels sprouts with broccoli.

In non-smokers with active genes there might still be a low protective effect.

When the results were stratified by smoking status, a protective effect was seen in smokers with both genes inactive (OR 0.31; 95% CI 0.12-0.82) but not in people with both genes active. In non-smokers, there seemed to be a protective effect regardless of genotype, however the results did not reach statistical significance.

By Randall Parker    2005 October 28 02:00 PM   Entry Permalink | Comments (5)
2005 March 17 Thursday
Every Other Day Fasting May Reduce Cancer Risk

Every other day fasting seems to provide mice with much of the known health benefits that calorie restriction diets are known to provide.

An apple a day keeps the doctor away, but could eating an apple every other day be better?

A new study by researchers at the University of California, Berkeley, raises such a possibility. It shows that healthy mice given only 5 percent fewer calories than mice allowed to eat freely experienced a significant reduction in cell proliferation in several tissues, considered an indicator for cancer risk. The key was that the mice eating 5 percent fewer calories were fed intermittently, or three days a week.

What is encouraging about the findings is that the reduction in cell proliferation from that intermittent feeding regimen was only slightly less than that of a more severe 33 percent reduction in calories. Until now, scientists have been certain only of a link between a more substantial calorie reduction and a reduction in the rate of cell proliferation.

The results of the study are scheduled to appear in the May 2005 issue of the American Journal of Physiology-Endocrinology and Metabolism, but are now available online.

"Cell proliferation is really the key to the modern epidemic of cancer," said Marc Hellerstein, professor of human nutrition in the Department of Nutritional Sciences and Toxicology at UC Berkeley's College of Natural Resources. Hellerstein is principal investigator of the study.

Cancer is essentially the uncontrolled division of cells, and its development typically requires the presence of multiple mutations. "Normally, a cell will try to fix any damage that has occurred to its DNA," said Hellerstein, "But, if it divides before it has a chance to fix the damage, then that damage becomes memorialized as a mutation in the offspring cells. Slowing down the rate of cell proliferation essentially buys time for the cells to repair genetic damage."

Cell proliferation contributes to carcinogenesis in a number of other ways, as well, collectively termed "cancer promotion."

Studies over the past 70 years have established that substantial calorie reduction - up to 50 percent in some studies - not only can reduce the rate of cell proliferation, it can extend the maximum life span of a variety of organisms, including rats, flies, worms and yeast. The results can be dramatic, with 30 to 70 percent increases in life span reported in the studies.

"Significant caloric restriction is the one and only thing that has been scientifically proven to extend life span," said Hellerstein, who has a joint appointment at UC San Francisco. He noted that while exercise and good nutrition can prevent premature death by disease, they have not been shown to extend a maximum life span.

Cutting calories has also been shown to reduce the development of cancer, enhance insulin sensitivity and lower the risk of heart disease.

The 5% reduction in calories used for mice translates into about 100 calories per day for humans. Many obese people overeat by about that amount and have little luck dieting to avoid those extra 100 calories. This brings into question the practicality of implementing this research in human diets.

Can some of the benefits of calorie restriction really be achieved by fasting every other day? To prove that this experiment would need to be run on mice and rats for years in order to find out whether this regimen increases their life expectancies and if so by how much.

Another question: Would one derive more benefit from even longer periods of fasting and eating? A week on and a week off perhaps? Or just 2 days fasting alternated with 2 days eating?

The researchers conducted several trials with a control group of mice that ate "ad lib," or freely. They compared the control group with mice that ate 5 percent fewer calories but were fed three times a week with mice that were given 33 percent fewer calories. Trial periods ranged from two weeks to three months.

As expected, the researchers found that mice on the 33 percent reduced calorie diet exhibited significantly decreased proliferation rates for skin, breast and T (lymphocyte) cells. The greatest effect was seen after one month on the regimen, when proliferation of skin cells registered only 61 percent of that for mice fed freely.

The surprising finding came with the results of the more modest 5 percent reduced calorie diet that was fed intermittently. Mice in this group had skin cell division rates that were 81 percent of those for mice fed freely.

Fasting every other day may decrease the chances of breast cancer the most. But I can not imagine many women being willing to fast every other day for weeks, months, and years on end.

In all cases, division rates for breast cells were reduced the most. Mice with the lowest calorie diet had breast cell proliferation results that were only 11 percent of those for the control group mice, and mice fed intermittently had results that were 37 percent of those for the control group.

The researchers said this may be partly related to the reduction in estrogen, which stimulates breast cell division. Tests revealed that the estrus cycle stopped for mice on the lowest calorie diet. The mice fed intermittently, on the other hand, continued to cycle regularly.

Results of the refeeding trials indicated that any weight lost during the calorie restriction period was regained once a normal feeding pattern was resumed.

Every other day fasting was tried on a small pilot study of humans.

A recent pilot study of 16 non-obese adults by researchers at the Pennington Biomedical Research Center in Louisiana found that eating only every other day was feasible when the participants successfully followed an alternate-day fasting regimen for three weeks. However, the people also reported feeling hungry and irritable on their fasting days.

The authors of the pilot study said that adding a small meal, fulfilling no more than 20 percent of the day's caloric needs, might just take the edge off and make the feeding pattern more palatable.

Would even shorter fasting periods provide any benefit? It would be interesting to see if any benefit could be derived by eating very day but having at least 12 hour stretches every day when no food is consumed. That might be more achievable. Don't eat before bedtime and then entirely skip breakfast and make lunch be the first meal of the day.

Even if intermittent fasting is eventually shown to deliver real human health benefits (and I expect it will) few people are going to be up for fasting every other day. Though perhaps more people could manage to do intermittent fasting than can manage to stay on a calorie restriction diet.

However, once safe appetite suppressant drugs are developed fasting could become a lot easier and may become popular as a method to slow aging and lower the risk of degenerative diseases. Appetite suppressants that could work for differing lengths of time would be handy. One could take an appetite suppressant for 12 hours or 24 hours depending on your fasting regime.

Another approach that may eventualy obviate the need for fasting is a class of drugs called calorie restriction mimetics. The idea behind calorie restriction mimetics (which are the subject of active research in a number of labs) is that they'll fool your metabolism into thinking you haven't eaten. Then your cells would throw themselves into the same state they go into when they are not getting as much calories. Appetite suppressants would remain useful for anyone who is overweight. But the benefit of fasting would be delivered by a separate calorie restriction mimetic drug.

Update: A previous study found that rodents genetically engineered to have less fat in fat cells lived longer without calorie restriction. This is not surprising because fat cells appear to excrete pro-inflammatory compounds. In fact. Rudolph Liebel of Columbia University says adipose fat cells excrete at least 25 hormones and other signalling compounds including adiponectin and resistin. The fatter you get the bigger the problem you'll have with accumulated damage from chronic inflammation. If we can develop treatments that prevent fat cells from converting excess calories into fat then we may be able to get many of the benefits of calorie restriction.

Also, see my previous post which reports that rodents which were made to skip meals had lower blood insulin and their brains were more resistant to damage from neurotoxins. Being skinny is good. Skipping meals is good too.

By Randall Parker    2005 March 17 02:05 PM   Entry Permalink | Comments (20)
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