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.
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.”
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.
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.
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.
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.
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.
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.
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.
“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.
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.
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.
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.
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