Life extension can't be found in most vitamin pills. But note they do not mention vitamin D.
Many people take antioxidants in the belief that they will prolong their life expectancy. However, data from 67 randomised trials that involved just under a quarter of a million people failed to support this idea, a Cochrane Systematic Review has discovered.
“We could find no evidence to support taking antioxidant supplements to reduce the risk of dying earlier in healthy people or patients with various diseases,” says Goran Bjelakovic, visiting researcher, who performed the systematic review at the Copenhagen Trial Unit at the Copenhagen University Hospital in Denmark.
The idea that antioxidants can extend life comes from human and animal laboratory research and has been boosted by some observational clinical studies. But other studies have indicated neutral or even harmful effects.
Cochrane reviews are based on peer reviewed published protocols that aim to identify randomised, published and unpublished, trials. Following Cochrane methodology, relevant data are extracted and pooled together from the identified trials, which are also assessed and subdivided into unbiased and biased in terms of methodology of their conductance, so that unbiased assessments of intervention effects can be conducted.
“The findings of our review show that if anything, people in trial groups given the antioxidants beta-carotene, vitamin A, and vitamin E showed increased rates of mortality. There was no indication that vitamin C and selenium may have positive or negative effects. So regarding these antioxidants we need more data from randomised trials,” says Bjelakovic. “The bottom line is that current evidence does not support the use of antioxidant supplements in the general healthy population or in patients with certain diseases.”
Nutrition still matters. Lots of types of food can cause harm. Charbroiled beef and foods with high glycemic index can cut your life expectancy while vegetables, fruits, and beans can keep you healthy longer. Try to eat good food while we wait for the biotechnological revolution to deliver real rejuvenating therapies. Within a couple of decades I expect life extension will come from stem cell therapies and gene therapies. We should try harder to make that real effective rejuvenation therapies come sooner.
I'm glad to see some medical experts have taken the time to write up a review of the lack of evidence for the claims that many glasses of water per day help you stay healthy. The idea that high water consumption delivers a health benefit is just a legend.
Washington, DC (Friday, March 28, 2008) — A recent look at what is known about the health effects of drinking water reveals that most supposed benefits are not backed by solid evidence. The findings indicate that most people do not need to worry about drinking their recommended 8 glasses of 8 ounces (“8x8”) of water per day. The editorial is published in the June 2008 issue of the Journal of the American Society of Nephrology (JASN).
While it is clear that humans cannot survive for longer than several days without water, very little research has assessed how average individuals’ health is affected by drinking extra fluids. Experts have claimed that ingesting water is helpful for everything from clearing toxins and keeping organs healthy to warding off weight gain and improving skin tone.
To investigate the true benefits of drinking water, Dan Negoianu, MD, and Stanley Goldfarb, MD, of the Renal, Electrolyte, and Hypertension Division at the University of Pennsylvania, in Philadelphia, PA, reviewed the published clinical studies on the topic. They found solid evidence that individuals in hot, dry climates, as well as athletes, have an increased need for water. In addition, people with certain diseases benefit from increased fluid intake. But no such data exist for average, healthy individuals. In addition, no single study indicates that people need to drink the recommended “8x8” amount of water each day. Indeed, it is unclear where this recommendation came from.
This scan of the literature included a look at studies related to the notion that increased water intake improves kidney function and helps to clear toxins. A variety of studies reveal that drinking water does have an impact on clearance of various substances by the kidney, including sodium and urea. However, these studies do not indicate any sort of clinical benefit that might result.
I've tried telling co-workers that their water habits were just the stuff of urban legends. But they were thoroughly wedded to their legends and kept on drinking. So just where did this urban legend originate? Maybe in some diet (wash that fat away) for losing weight? Or as part of some 1960s or 1970s fad about body detoxing?
How many weeks has it been since I last nagged you about how most of you don't get enough vitamin D? Vitamin D, which helps the immune system function better, seems to cut the incidence of the autoimmune disorder type 1 diabetes.
Vitamin D supplements in early childhood may ward off the development of type 1 diabetes in later life, reveals a research review published ahead of print in the Archives of Disease in Childhood.
Type 1 diabetes is an autoimmune disorder, in which insulin producing beta cells in the pancreas are destroyed by the body’s own immune system, starting in early infancy. The disease is most common among people of European descent, with around 2 million Europeans and North Americans affected.
Its incidence is rising at roughly 3% a year, and it is estimated that new cases will have risen 40% between 2000 and 2010.
A trawl of published evidence on vitamin D supplementation in children produced five suitable studies, the pooled data from which were re-analysed.
The results showed that children given additional vitamin D were around 30% less likely to develop type 1 diabetes compared with those not given the supplement.
Vitamin D also might cut your risk of the autoimmune disease rheumatoid arthritis (and see here too). Risk of Multiple Sclerosis also appears inversely associated with blood vitamin D levels. Avoid autoimmune disorders. Get enough vitamin D.
Eat broccoli and other cruciferous vegetables for sulforaphane.
Eat your broccoli! That's the advice from UCLA researchers who have found that a chemical in broccoli and other cruciferous vegetables may hold a key to restoring the body's immunity, which declines as we age.
Published in this week's online edition of the Journal of Allergy and Clinical Immunology, the study findings show that sulforaphane, a chemical in broccoli, switches on a set of antioxidant genes and enzymes in specific immune cells, which then combat the injurious effects of molecules known as free radicals that can damage cells and lead to disease.
Immune system aging sets you up for getting killed by pneumonia or flu or a bacterial infection picked up while at a hospital. In fact immune system aging probably makes us more vulnerable to cancer and people with especially capable immune systems are probably at much lower risk of getting cancer. So keeping your immune system younger yields a big benefit.
The UCLA team not only found that the direct administration of sulforaphane in broccoli reversed the decline in cellular immune function in old mice, but they witnessed similar results when they took individual immune cells from old mice, treated those cells with the chemical outside the body and then placed the treated cells back into a recipient animal.
In particular, the scientists discovered that dendritic cells, which introduce infectious agents and foreign substances to the immune system, were particularly effective in restoring immune function in aged animals when treated with sulforaphane.
"We found that treating older mice with sulforaphane increased the immune response to the level of younger mice," said Hyon-Jeen Kim, first author and research scientist at the Geffen School.
To investigate how the chemical in broccoli increased the immune system's response, the UCLA group confirmed that sulforaphane interacts with a protein called Nrf2, which serves as a master regulator of the body's overall antioxidant response and is capable of switching on hundreds of antioxidant and rejuvenating genes and enzymes.
Nel said that the chemistry leading to activation of this gene-regulation pathway could be a platform for drug discovery and vaccine development to boost the decline of immune function in elderly people.
Broccoli sprouts are the best known source of sulforaphane.
Sulforaphane concentration in broccoli sprout (1153 mg/100 g dry weight) was about 10 times higher than that of mature broccoli (44-171 mg/100 g dry weight).
Extracts of 3-day-old broccoli sprouts (containing either glucoraphanin or sulforaphane as the principal enzyme inducer) were highly effective in reducing the incidence, multiplicity, and rate of development of mammary tumors in dimethylbenz(a)anthracene-treated rats. Notably, sprouts of many broccoli cultivars contain negligible quantities of indole glucosinolates, which predominate in the mature vegetable and may give rise to degradation products (e.g., indole-3-carbinol) that can enhance tumorigenesis. Hence, small quantities of crucifer sprouts may protect against the risk of cancer as effectively as much larger quantities of mature vegetables of the same variety.
Some Johns Hopkins researchers have even founded a company that sells teas fortified with sulforaphane.
You probably ought to eat some high vitamin E foods.
Low serum concentration of vitamin E, an indication of poor nutrition, is associated with physical decline for older persons, according to a study in the January 23 issue of JAMA.
“The decline in physical function that occurs with aging often represents the early stage of a continuum leading to disability and other important adverse outcomes such as institutionalization,” the authors write. Understanding the mechanisms associated with this process has been identified as a priority. The potential harmful effect of poor nutrition on physical function in older persons is not well understood.
Benedetta Bartali, R.D., Ph.D., of Yale University School of Medicine, New Haven, Conn., and colleagues conducted a study to determine whether a low concentration of specific micronutrients is associated with subsequent decline in physical function. The study included 698 community-living persons 65 years or older who were randomly selected from a population registry in Tuscany, Italy. To measure nutritional status and physical function, participants completed a baseline examination, conducted from November 1998 through May 2000, and 3-year follow-up assessments from November 2001 through March 2003. Measurements were obtained for several micronutrients, including serum folate and vitamins B6, B12, D and E. Decline in physical function was defined as a loss of at least 1 point in the Short Physical Performance Battery during the follow-up, which included three objective tests of physical function.
The average decline in physical function score was 1.1 point. In analyses adjusted for other factors, only a low concentration of vitamin E was significantly associated with subsequent decline in physical function. Additional analyses indicated that age older than 81 years and vitamin E (in participants 70-80 years) were the strongest determinants of decline in physical function.
“The hypothesis that antioxidants [such as vitamin E] play a role in the etiology of decline in physical function and disability is supported by our previous findings and other studies suggesting that oxidative stress is involved in muscle fatigue and that antioxidants play a preventive role in muscle damage by reducing oxidative injury,” the authors write.
“Thus, at least 3 different mechanisms may explain the effect of low concentration of vitamin E on subsequent decline in physical function: (1) increased oxidative stress leading to muscle or DNA damage, (2) exacerbation of atherosclerosis or other pathologic conditions, and (3) development of neurodegenerative disorders.”
Participants in the study did not take vitamin supplements and the authors do not recommend vitamin E supplements to increase levels. They state, “Approximately 15 to 30 mg/d of dietary alpha-tocopherol [a component of vitamin E] is needed … this amount can be easily reached through diet, from sources such as almonds, tomato sauce, and sunflower seeds among others.”
Can you be bothered to improve your diet? It probably won't pay off much for years. Can you make a sustained change for a distant pay-off?
Eat some nuts. They have magnesium too.
Women who have higher dietary intake of lutein and zeaxanthin—compounds found in yellow or dark, leafy vegetables—as well as more vitamin E from food and supplements appear to have a lower risk for developing cataracts, according to a report in the January issue of Archives of Ophthalmology, one of the JAMA/Archives journals.
“The oxidative hypothesis of cataract formation posits that reactive oxygen species can damage lens proteins and fiber cell membranes and that nutrients with antioxidant capabilities can protect against these changes,” the authors write as background information in the article. Vitamin E, vitamin C, beta carotene, lutein and zeaxanthin are all believed to have antioxidant properties. Lutein and zeaxanthin are the only carotenoids—yellow plant pigments—present in the lens of the human eye and may also protect against cataracts by filtering harmful blue light.
William G. Christen, Sc.D., of Brigham & Women’s Hospital and Harvard Medical School, Boston, and colleagues analyzed dietary information from 35,551 female health professionals who enrolled in the Women’s Health Study in 1993. The women were then followed for an average of 10 years, and the diets of those who developed cataracts were compared with the diets of those who did not.
A total of 2,031 women developed cataracts during the study. When the participants were split into five groups based on the amount of lutein and zeaxanthin they consumed, those in the group who consumed the most (about 6,716 micrograms per day) had an 18 percent lower chance of developing cataracts than those who consumed the least (1,177 micrograms per day). The one-fifth who consumed the most vitamin E from food and supplements—about 262.4 milligrams per day—were 14 percent less likely than the one-fifth who got the least (4.4 milligrams per day).
Of course getting lots of vegetables will reduce your risk of many other diseases as well. But people like the taste of cheeseburgers and fries more than veggies.
At least in mice lipoic acid reduces the development of cardiovascular disease.
CORVALLIS, Ore. – A new study done with mice has discovered that supplements of lipoic acid can inhibit formation of arterial lesions, lower triglycerides, and reduce blood vessel inflammation and weight gain – all key issues for addressing cardiovascular disease.
Lipoic acid is involved in energy metabolism. Possibly it delivers a benefit by keeping energy generation up in cells in the circulatory system. Imagine we had a better way to keep up energy generation, for example a gene therapy that could replace damaged mitochondrial genes as we age. Well, our blood vessels might remain unclogged for decades longer.
Although the results cannot be directly extrapolated beyond the laboratory, researchers report that “they strongly suggest that lipoic acid supplementation may be useful as an inexpensive but effective intervention strategy . . . reducing known risk factors for the development of atherosclerosis and other inflammatory vascular diseases in humans.”
The findings were made by scientists from the Linus Pauling Institute and College of Veterinary Medicine at Oregon State University, and the Department of Medicine at the University of Washington. They were just published in Circulation, a journal of the American Heart Association.
Heart disease is the leading cause of death in the United States.
The study found that lipoic acid supplements reduced atherosclerotic lesion formation in two types of mice that are widely used to study cardiovascular disease, by 55 percent and 40 percent, respectively. The supplements were also associated with almost 40 percent less body weight gain, and lower levels of triglycerides in very low-density lipoproteins.
The reduced body weight gain: Do we gain weight as we age because our metabolisms slow down?
The dose used is the equivalent of 2 grams per day for humans. Mind you, your own arteries might be clean and you ought to eat a better diet of the sort that reduces cardiovascular (and cancer) risk before taking lipoic acid.
Alpha lipoic acid is a naturally occurring nutrient found at low levels in green leafy vegetables, potatoes and meats, especially organ meats such as kidney, heart or liver. The amounts used in this research would not be obtainable by any normal diet, researchers said, and for human consumption might equate to supplements of about 2,000 milligrams per day. Even at low, normal, dietary levels, the compound can play a key role in energy metabolism.
I would rather have gene therapies and cell therapies that turn back the biological clock than take vitamins and other nutrients in pills.
Time for another study on the benefits of vitamin D. The D2 form of vitamin D appears to reduce the frequency of falls among older women.
Vitamin D2 supplements appear to reduce the risk of falls among women with a history of falling and low blood vitamin D levels living in sunny climates, especially during the winter, according to a report in the January 14 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
“Approximately one-third of women older than 65 years fall each year, and 6 percent sustain a fracture as a result of the fall,” the authors write as background information in the article. “In addition, fear of falling is a major problem in older people.”
Richard L. Prince, M.D., of the Sir Charles Gairdner Hospital, Nedlands, Australia, and colleagues conducted a year-long clinical trial of 302 women age 70 to 90 years living in Perth, Australia. Because vitamin D is produced in response to sun exposure and the study was completed in a sunny climate, the researchers selected women with blood vitamin D levels below the median for the area (24 nanograms per milliliter). All participants had a history of falling in the previous year and received 1,000 milligrams of calcium citrate per day. Half were then randomly assigned to take either 1,000 international units of vitamin D2 (ergocalciferol) and half took an identical placebo. Data on falls were collected from participants every six weeks.
Eighty women (53 percent) in the vitamin D2 group and 95 women (62.9 percent) in the control group fell at least once during the study period. After adjusting for height, which affected the risk of falling and was significantly different between the two groups, vitamin D2 therapy reduced the risk of having at least one fall by 19 percent. “When those who fell were grouped by the season of first fall or the number of falls they had, ergocalciferol treatment reduced the risk of having the first fall in winter and spring but not in summer and autumn, and reduced the risk of having one fall but not multiple falls,” the authors write.
There is the falling. But there are also the injuries sustained by the falling. There is the substantial possibility that the vitamin D supplementation will reduce the risks of bone breakage per fall as well as reducing the risk of falling in the first place.
These results imply that older folks are at greater risk of falling down in the fall and winter. Interesting.
“It is interesting that the ergocalciferol therapy effect was confined to those who were to sustain one fall but not those destined to have more than one fall,” the authors write. “Older people who fall frequently tend to have more risk factors for falling, including greater degrees of disability and poorer levels of physical function.” It is possible that chemically correcting vitamin D levels in the blood is insufficient to prevent falls in these individuals, they note. “Ergocalciferol, 1,000 international units per day, added to a high calcium intake is associated with 23 percent reduction of the risk of falling in winter/spring to the same level as in summer/autumn,” the authors conclude.
In the comments section of my post on the value of vitamin D as D2 or D3 a researcher from UCSD pointed out that the study in that post doesn't prove the stated conclusion of the study. Well, be aware that when reading these sorts of posts that we aren't necessarily seeing the critical reactions to the studies (though in that case we did). Still, enough of the benefits of vitamin D are well established that even if some of the theorized benefits don't hold up getting more of the nutrient looks like a big benefit for most people in industrialized societies.
If you've been persuaded (certainly I've tried) that you need more vitamin D maybe (but probably not) you've wondered what form of vitamin D you should take. Well renowned vitamin D researcher Michael Holick, PhD, MD, basically has found that you can take vitamin D as D2 or D3 without worrying which is more potent.
Boston, MA— Researchers from Boston University School of Medicine (BUSM) have found that vitamin D2 is equally as effective as vitamin D3 in maintaining 25-hydroxyvitamin D status. The study appears online in the December 2007 issue of the Journal of Clinical Endocrinology & Metabolism.
Researchers studied healthy adults aged 18-84 who received either placebo, 1,000 International Units (IU) of vitamin D3, 1,000 IU of vitamin D2, or 500 IU of vitamin D2 plus 500 IU of vitamin D3 daily for three months at the end of winter to establish what effect it had on circulating levels of total 25 (OH)D as well as 25(OH)D2 and 25(OH)D3. Sixty percent of the adults were vitamin D deficient at the start of the study.
Adults who received the placebo capsule daily for three months demonstrated no significant change in their total 25(OH)D levels during the winter and early spring. Adults who ingested 1,000 vitamin D2/d gradually increased their total 25(OH)D levels during the first six weeks. Adults who ingested 1,000 IU of vitamin D3 had a baseline 25(OH)D that was statistically no different from the baselines of either the placebo group or the groups that took 1,000 IU of vitamin D2/d or 500 IU vitamin D2 plus 500 IU vitamin D3/d. The vitamin D3 group increased their serum 25(OH)D levels similar to that of the group that ingested vitamin D2.
The circulating levels of 25-hydroxyvitamin D increased to the same extent in the groups that received 1,000 IU daily as vitamin D2, vitamin D3, or a combination of 500 IU vitamin D2 and 500 IU vitamin D3. The 25-hydroxyvitamin D3 levels did not change in the group that received 1,000 IU vitamin D2 daily. One thousand IU of vitamin D2 or vitamin D3 did not raise 25-hydroxyvitamin D levels in vitamin D deficient subjects above 30 ng/ml.
Even if you haven't wondered about this particular burning vitamin D research question at least this serves as a reminder that vitamin D probably will reduce your odds of cancer, auto-immune disorders, infections, osteoporosis, and assorted other maladies.
Fasting once a month for 1 day substantially cuts artery disease risk.
Mormons have less heart disease — something doctors have long chalked up to their religion's ban on smoking. New research suggests that another of their "clean living" habits also may be helping their hearts: fasting for one day each month.
A study in Utah, where the Church of Jesus Christ of Latter-Day Saints is based, found that people who skipped meals once a month were about 40 percent less likely to be diagnosed with clogged arteries than those who did not regularly fast.
Thanks to James Bowery for the tip.
Though more than 90% of the people studied were Mormons, the findings held true even in those who had a different religious preference, says Benjamin D. Horne, PhD, director of cardiovascular and genetic epidemiology at Intermountain Medical Center in Salt Lake City.
Yes friends, even you can benefit. Step right up and choose your day to go hungry. I'm thinking the fasting day needs to be a day where there's a whole lot of constant distraction so you don't have to spend the day thinking how hungry you are. Maybe we need fasting amusement parks where you spend all day riding roller coasters.
The research was conducted at LDS Hospital using the Intermountain Heart Collaborative Study registry, made up of patients who had heart angiography between 1994 and 2002. The researchers focused on patients who are LDS to see if other church-dictated practices besides not smoking had an impact, said Benjamin Horne, director of cardiovascular and genetic epidemiology, now at the new Intermountain Medical Center. He's also an adjunct professor at the University of Utah.
Researchers looked at data from more than 4,600 people, average age 64, who had come through the cardiac cath lab, to see the degree of risk for someone who was LDS compared to others. They focused on those with obvious coronary artery disease (CAD), defined as 70 percent narrowing or blockage in at least one artery, and those who had little or no CAD (less than 10 percent narrowing). They found that while 66 percent of others had CAD, only 61 percent of LDS members did.
I am going to found a church which preaches a high vegetable, high fruit, and low glycemic index diet. Maybe call it the SENS Church for Strategies for Engineered Negligible Senescence Church. I need to find a barrel to look into to receive divine messages. What are my prospects for success?
SENS believers, you've got to suffer hunger pangs once a month to survive until the redemption of rejuvenation therapies. Once we receive the rejuvenation therapies we will enter the promised land of no harm daily Roman style feasts.
Instead of avoiding fats it probably makes a lot more sense to eat less carbo.
Eating foods high on the glycemic index, which measures the effect of carbohydrates on blood glucose levels, may be associated with the risk for developing type 2 diabetes in Chinese women and in African-American women, according to two studies in the November 26 issue of Archives of Internal Medicine, one of the JAMA/Archives journals. However, eating more cereal fiber may be associated with a reduced risk for type 2 diabetes in African-American women.
Researchers remain uncertain regarding exactly how diet, including carbohydrate intake, affects the development of type 2 diabetes, according to background information in the articles. Studies have revealed that the body absorbs carbohydrates from different foods at different rates. This leads to varying effects on levels of blood glucose and the hormone insulin, which converts glucose into energy. Foods high on the glycemic index, such as rice and other simple carbohydrates, cause a rapid spike and then a drop in blood glucose, whereas high-fiber foods tend to be lower on the glycemic index and have a more gradual effect. Some evidence has linked high–glycemic index foods with the risk of developing type 2 diabetes.
In one study, Supriya Krishnan, D.Sc., of Boston University School of Public Health, and colleagues examined data from 40,078 U.S. black women who filled out a food questionnaire in 1995. The glycemic index and glycemic load—a measure of the amount of carbohydrates from glucose—were calculated. Every two years through 2003, the women answered follow-up questionnaires about their weight, health and other factors.
A high carbohydrate diet with high glycemic index foods almost doubled the risk of type 2 insulin resistant diabetes.
During the study, 1,608 of the women developed diabetes. Women who consumed more carbohydrates overall were more likely to develop diabetes—when they were split into five groups based on carbohydrate intake, those in the group consuming the most (about 337.6 grams per day) had a 28 percent higher risk than those in the group consuming the least (about 263.5 grams per day). Women who ate diets with a higher glycemic index and who ate more staples such as bread, noodles and rice specifically also had an increased risk. Women who ate 300 grams or more of rice per day were 78 percent more likely to develop diabetes than those who ate less than 200 grams per day.
Chinese women who eat more rice are at higher risk of type 2 diabetes mellitus. Cut way back on grains consumption. If you eat grains then at least eat whole grains. Also, pasta is lower in glycemic index than bread. Check out this long list of foods and their glycemic index values. Shift toward beans and away from grains. Eat more fruits and vegetables and nuts. Also see this cool sortable database of glycemic index and glycemic load of foods.
Yet another reminder that you probably ought to increase your vitamin D intake.
WASHINGTON, D.C. (November 8, 2007)- There is a new reason for the 76 million baby boomers to grab a glass of milk. Vitamin D, a key nutrient in milk, could have aging benefits linked to reduced inflammation, according to a new study published in the American Journal of Clinical Nutrition.
In a genetic study of more than 2,100 female twin pairs ages 19-79, British and American researchers found that higher vitamin D levels were linked to improved genetic measures of lifelong aging and chronic stress. Using a genetic marker called leukocyte telomere length (LTL), they found those with the highest vitamin D levels had longer LTL, indicating lower levels of inflammation and body stress. The telomere difference between those with the highest and lowest vitamin D levels was equivalent to 5 years of aging.
Previous research has found that shortened LTL is linked to risk for heart disease and could be an indication of chronic inflammation – a key determinant in the biology of aging. While there are several lifestyle factors that affect telomere length (obesity, smoking and lack of physical activity), the researchers noted that boosting vitamin D levels is a simple change to affect this important marker.
Why use telomere length as a proxy for aging and stress? See my post Telomere Length Indicates Mortality Risk.
Also see my posts Chronic Stress Accelerates Aging As Measured By Telomere Length and Telomeres Wear Down Quicker In Men Than Women. Don't stress out guys. It is slowly killing you.
If you have chronic back pain ask yourself whether you have enough vitamin D in your blood.
Approximately one in four patients who suffer from chronic pain also have inadequate blood levels of vitamin D, possibly contributing to their ongoing pain, according to a new study. Patients lacking sufficient vitamin D also required higher doses of morphine for a longer period of time.
Researchers recorded the serum vitamin D levels of 267 adults undergoing outpatient treatment for chronic pain, as well as their pain medication (morphine) dose and duration of use, and physical and general health functioning.
Of the patients tested, 26 percent had vitamin D inadequacy. Among these patients, the morphine dose was nearly twice that of the group with adequate vitamin D levels. In addition, the vitamin D inadequacy group used morphine for an average of 71.1 months versus 43.8 months. The vitamin D deficient group also reported lower levels of physical functioning and had a poorer view of their overall health.
It has long been known that inadequate levels of vitamin D can cause pain and muscle weakness, according to the study author, W. Michael Hooten, M.D., medical director, and anesthesiologist at Mayo Comprehensive Pain Rehabilitation Center, Rochester, Minnesota. Previous studies also have suggested that pain-related symptoms of vitamin D inadequacy respond poorly to pain medications.
I think its been a few weeks since I last gave you all a reason to get more vitamin D in your body. Is this nagging doing any good?
Avoid the carbohydrates which digest quickly and your eyes won't age as rapidly.
Eating fewer refined carbohydrates may slow the progression of age-related macular degeneration (AMD), according to a new study from researchers at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University.
AMD results in partial or total blindness in 7 to 15% of the elderly, according to the Eye Diseases Prevalence Research Group. “Dietary changes may be the most practical and cost-effective prevention method to combat progression of AMD,” says Allen Taylor, PhD, director of the Laboratory for Nutrition and Vision Research at the USDA HNRCA. “It is surprising there is so little attention focused on the relationship between AMD and carbohydrates.”
The current study, published in the October issue of the American Journal of Clinical Nutrition, builds on a recent analysis by Taylor and colleagues that found men and women older than 55 who consumed diets with higher-than-average dietary glycemic index foods appeared to have an increased risk for both early and later stages of AMD.
Eat less white bread and more whole grains. Or shift from grains toward beans and the lower glycemic index rices (not that fluffy stuff you find in Chinese restaurants).
A lower glycemic index diet which slows and delays development of AMD probably has more general effects on the rate of aging through out the body.
“Our data showed those people in the high-glycemic-index group were at greater risk of AMD progression, especially those already in the late stages,” says first author Chung-Jung Chiu, DDS, PhD, scientist in the Laboratory for Nutrition and Vision Research at the USDA HNRCA and assistant professor at Tufts University School of Medicine. “Participants who consumed the most refined carbohydrates were 17 percent more likely to develop blinding AMD than the group that consumed the least.”
If you can slow your rate of aging by a small amount doing so might allow you to live long enough to still be alive and mentally mostly intact by the time rejuvenation therapies become available. If you want to shift toward a lower glycemic index diet then see this chart of glycemic index in foods.
Make sure you get enough vitamin D.
HONOLULU, Sept. 20 – Women with low levels of vitamin D have an increased risk of hip fracture, according to a study led by the University of Pittsburgh Graduate School of Public Health presented this week at the 29th annual meeting of the American Society for Bone and Mineral Research at the Hawaii Convention Center.
Jane A. Cauley, Dr.P.H., professor of epidemiology, and colleagues evaluated patient data on 400 women enrolled in the Women’s Health Initiative Observational Study Cohort who had experienced hip fracture, confirmed by their medical record, over a median of 7.1 years. Levels of 25 hydroxyvitamin D, an indicator of vitamin D status, in the bloodstream were measured for these patients and compared with those of a control group matched for age, race, ethnicity and the date of relevant blood work. As vitamin D concentrations decreased, the risk of hip fractures climbed.
“The risk of hip fractures was 77 percent higher among women whose 25 hydroxyvitamin D levels were at the lowest concentrations,” said Dr. Cauley, who has spent much of the past 15 years investigating the physical changes that take place in postmenopausal women. “This effect persisted even when we adjusted for other risk factors such as body mass index, family history of hip fracture, smoking, alcohol use and calcium and vitamin D intake.”
Vitamin D deficiency might well cause more damage than any other nutrient deficiency in industrialized countries.
Juvenile onset type 1 diabetes is an auto-immune disease where the body's immune cells attack pancreatic cells that make insulin. Omega-3 fatty acids, which are known to have anti-inflammatory properties, appear to substantially reduce risk of type 1 diabetes.
Preliminary research suggests that in children at increased risk for type 1 diabetes, dietary intake of omega-3 fatty acids was associated with a reduced risk of pancreatic islet autoimmunity, which is linked to the development of diabetes, according to an article in the Sept. 26 issue of JAMA.
“Type 1 diabetes mellitus is an autoimmune disease that is characterized by the destruction of insulin-producing beta cells in the pancreatic islets. Although it is not yet known what initiates the autoimmune process, it is likely that both genetic background and environmental factors contribute to the disease process,” the authors write. Certain dietary factors have been associated with the onset of type 1 diabetes as well as the autoimmune process that leads to the disease.
Jill M. Norris, M.P.H., Ph.D., of the University of Colorado at Denver and Health Sciences Center, Denver, and colleagues examined whether consumption of omega-3 and omega-6 fatty acids are associated with the development of pancreatic islet autoimmunity (IA; development of antibodies against the cells in pancreas that produce insulin) in children. The study, conducted between 1994 and 2006, included 1,770 children at increased risk for type 1 diabetes, defined as either possession of a high diabetes risk HLA (human leukocyte antigen) genotype or having a sibling or parent with type 1 diabetes. The average age at follow-up was 6.2 years. Islet autoimmunity was assessed in association with reported dietary intake of polyunsaturated fatty acids starting at age 1 year. Fish is the primary source of marine polyunsaturated fatty acids. Childhood diet was measured using a food frequency questionnaire (FFQ).
A case-cohort study (n = 244) was also conducted in which risk of IA by polyunsaturated fatty acid content of erythrocyte membranes (outer portion of the red blood cell) was examined.
Fifty-eight children became positive for IA during follow-up. Adjusting for HLA genotype, family history of type 1 diabetes, caloric intake, and total omega-6 fatty acid intake, total omega-3 fatty acid intake was inversely associated with IA risk (a 55 percent reduced risk). The association was strengthened when the definition of the outcome was limited to those positive for two or more autoantibodies. In the case-cohort study, omega-3 fatty acid content of erythrocyte membranes was associated with a 37 percent decreased risk of IA.
Children who eat fish are also getting more vitamin D and hence might have less auto-immune disease for that reason. It has long been noticed that in the United States the incidence of multiple sclerosis (such is very likely an auto-immune disorder) is higher at northern latitudes. Further north people spend more time in-doors and get less vitamin D made in their skin as a result of sunlight hitting their skin. So the effect here might not entirely come from the omega-3 fatty acids. Either way, this result is an argument for eating fish. The research on omega 3 fatty acids and chronic inflammatory diseases also supports the idea that fish oil delivers real benefit.
Both reported diets and blood tests correlated with measured autoimmune response.
Parents were surveyed annually about what their children ate and children were tested for specific antibodies in the blood that marked the destruction of the cells that make insulin (i.e. diabetes autoimmunity). In a subset of this population, the researchers also examined whether risk of diabetes autoimmunity was associated with omega-3 fatty acid content of red blood cell membranes, which is a marker of omega-3 fatty acid status.
Of the children followed, those who reported eating more omega-3 fatty acids were less likely to develop diabetes autoimmunity. The investigators also showed that omega-3 fatty acid content of red blood cell membranes was inversely associated with risk of diabetes autoimmunity.
I go out of my way to make sure I get enough omega 3 fatty acids and eat salmon several times a week. Suggest you do the same.
Time for yet another FuturePundit post on why vitamin D is probably the best nutrient to take as a supplement. A meta-analysis of 18 randomized controlled trials using vitamin D supplements found a 7% lower risk of death among vitamin D supplement users.
Individuals who take vitamin D supplements appear to have a lower risk of death from any cause over an average follow-up time of six-years, according to a meta-analysis of 18 previously published studies in the September 10 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
Past studies have suggested that deficiencies in vitamin D might be associated with a higher risk of death from cancer, heart disease and diabetes—illnesses that account for 60 percent to 70 percent of deaths in high-income nations, according to background information in the article. “If the associations made between vitamin D and these conditions were consistent, then interventions effectively strengthening vitamin D status should result in reduced total mortality,” the authors write.
Philippe Autier, M.D., of the International Agency for Research on Cancer, Lyon, France, and Sara Gandini, Ph.D., of the European Institute of Oncology, Milano, Italy, searched for randomized controlled trials of vitamin D supplements published before November 2006. They analyzed 18 separate trials that included 57,311 participants and evaluated doses of vitamin D ranging from 300 to 2,000 international units, with an average dose of 528 international units. Most commercially available supplements contain between 400 and 600 international units.
Over an average follow-up period of 5.7 years, 4,777 of the participants died. Individuals who took vitamin D had a 7 percent lower risk of death than those who did not. In the nine trials that collected blood samples, those who took supplements had an average 1.4- to 5.2-fold higher blood level of vitamin D than those who did not.
The reduction in all cause mortality suggests that vitamin D doesn't just reduce one risk while boosting another. Too many things that might help in some ways end up hurting in other ways. Vitamin D looks like a big net benefit.
Aside from vitamin D I'm hard pressed to think of a single vitamin that holds the promise of such a large benefit if taken as a supplement by most people in developed countries. Most likely you could do much better for your health by eating more vegetables and fruits than by taking any other vitamin.
Update: Vitamin D probably reduces the risk of preeclampsia too.
Vitamin D deficiency early in pregnancy is associated with a five-fold increased risk of preeclampsia, according to a study from the University of Pittsburgh Schools of the Health Sciences reported this week in the Journal of Clinical Endocrinology and Metabolism.
The Hannaford Brothers Company grocery store chain in Maine tried putting stars on foods (the more stars the better the food) to steer customers toward healthier food choices. Given better information about the health benefits of foods while in grocery stores customers will select healthier meats but won't buy more vegetables.
After analyzing a year’s worth of sales data, Hannaford found that customers tended to buy leaner cuts of meat. Sales of ground beef with stars on their labels increased 7 percent, and sales of chicken that had a star rating rose 5 percent. Sales of ground beef labeled with no stars dropped by 5 percent, while sales of chicken that had a zero-star rating declined 3 percent. Similarly, sales of whole milk, which received no stars, declined by 4 percent, while sales of fat-free milk (three stars) increased 1 percent. Sales of fruits and vegetables, however, remained about the same as they did before the ratings were introduced. All fresh produce received stars.
People ask me to write a post describing the ideal diet. Well, the best thing you can do to improve your health is to eat lots more vegetables and fruits and less of just about everything else. But people want fats and red meat and starchy foods. They don't want vegetables. This latest result demonstrates this basic problem with the human diet. We have food instincts that are aimed at ensuring survival in environments where food is in short supply. So our instincts lead us to eat foods which are far from optimal for us today.
Antioxidant vitamins C, E, and beta carotene failed to cut risk of heart attacks in women. (but remember that you probably need more vitamin D)
Vitamins C and E and beta carotene, either individually or in combination, do not appear to reduce the risk of cardiovascular events or death among women at high risk for heart disease, according to a report in the August 13/27 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
The search for why vegetables and fruits improve your health isn't finding that antioxidant vitamins are the cause.
Oxidative damage—harm to cells caused by exposure to oxygen—may contribute to the development of cardiovascular disease, according to background information in the article. In addition, compounds known as free radicals may damage artery linings, encourage blood clots and alter the function of blood vessels. “Antioxidants scavenge free radicals and limit the damage they can cause,” the authors write. “Diets high in fruit and vegetable intake, and thus rich in such antioxidants, have been associated with reduced rates of coronary heart disease and stroke. Vitamins C and E and beta carotene are potential mediators of the apparent protective effect of a plant-based diet on cardiovascular disease.”
Nancy R. Cook, Sc.D., of Brigham & Women’s Hospital and Harvard Medical School, Boston, and colleagues tested the effects of these compounds in the Women’s Antioxidant Cardiovascular Study, which followed 8,171 women 40 years or older (average age 60.6) beginning in 1995 to 1996. The women, who either had a history of cardiovascular disease or three or more risk factors, were randomly assigned to take 500 milligrams of ascorbic acid (vitamin C) or placebo every day; 600 international units of vitamin E or placebo every other day; and 50 milligrams of beta carotene or placebo every other day. Participants were followed up for the occurrence of heart events (including stroke, heart attack and bypass surgery) or death through 2005.
Vitamin C and E in combination might cut risk of stroke.
During the average study period of 9.4 years, 1,450 women had one or more cardiovascular events, including 274 heart attacks, 298 strokes, 889 coronary revascularization procedures (bypass surgery or angioplasty) and 395 cardiovascular deaths (out of a total 995 deaths). “There was no overall effect of ascorbic acid, vitamin E or beta carotene on the primary combined end point or on the individual secondary outcomes of myocardial infarction, stroke, coronary revascularization or cardiovascular disease death,” the authors write. “There were no significant interactions between agents for the primary end point, but those randomized to both active ascorbic acid and vitamin E experienced fewer strokes.”
While scientists try to figure out what exactly in fruits and vegetables extend the lives of many people your best bet is to eat more fruits and vegetables. Vegetables are boring. But vegetables are good for you. They are probably good for you for the same reason they are boring: They have low glycemic index and so do not taste as sweet as other higher glycemic index foods. Also, their fibers have tastes that aren't as appealing as starchy grains. If you want to live longer then find ways to make vegetables more palatable.
If you can't find it in you to eat lots of vegetables (and few people can) then you should find the time to promote accelerated research into the development of therapies that reverse the damage caused by eating lots of meat and grains. Donate to research. Ask your government to fund more research into stem cells and gene therapy. Invest in biotech start-ups.
Scientists have provided new evidence that using more fish oil than vegetable oil in the diet decreases the formation of chemicals called prostanoids, which, when produced in excess, increase inflammation in various tissues and organs. The results, by William L. Smith, Professor and Chair of Biological Chemistry at the University of Michigan, Ann Arbor, and colleagues, may help in designing new anti-inflammatory drugs with fewer side effects than the ones currently available.
“Prostanoids help control blood pressure, fight allergies, and modulate inflammation, but too much of them – especially those made from vegetable oils – can also lead to increased pain, swelling, and redness in various tissues,” Smith says. “Our study shows that prostanoids made from fish oil are less effective at causing pain and swelling than those made from vegetable oil and that adding fish oil to the diet decreases the amount of prostanoids made from vegetable oil.”
Increased expression of genes involved in inflammation is one of the characteristics of aging tissues. Reducing the extent of this age-related inflammation will probably yield health dividends.
The experiments were done with cell cultures.
Smith and colleagues looked at the mutual effects of both oils by changing their respective amounts in cultured cells. As expected, a relative increase in fish oil lowered the amount of prostanoids from vegetable oil, although not always in the expected proportions.
Both fish and vegetable oils are converted into prostanoids through chemical reactions that are aided by enzymes called cyclo-oxygenases (COX), two types of which – COX-1 and COX-2 – are involved in the reactions. The scientists showed that, in reactions involving COX-1, when more fish oil is present, it preferentially binds to COX-1, thus limiting vegetable oil’s access to this enzyme. But in reactions involving COX-2, increasing the amount of fish oil did not change the way it binds to COX-2, so a significant portion of vegetable oil was still converted to prostanoids.
Eat more fish oils to get more omega 3 fatty acids. Also, eat less corn oil and other oils which have more omega 6 fatty acids.
One cause of blindness in old age happens more often in people who eat high glycemic index diets.
BOSTON -- Age-related macular degeneration (AMD) and its associated vision loss may be connected to the quality of carbohydrates an individual consumes. In a study published in the July issue of the American Journal of Clinical Nutrition, Allen Taylor, PhD, director of the Laboratory for Nutrition and Vision Research at the Jean Mayer USDA Human Nutrition Research Center on Aging (USDA HNRCA) at Tufts University, and colleagues confirmed earlier findings linking dietary glycemic index with the risk of developing AMD.
"Men and women who consumed diets with a higher glycemic index than average for their gender and age-group were at greater risk of developing advanced AMD," corresponding author Taylor says. "The severity of AMD increased with increasing dietary glycemic index."
The carbohydrates in lower glycemic index foods break down more slowly into simple sugars in the digestive tract. Therefore the sugar enters the bloodstream more slowly and blood sugar levels do not spike as high. It is those high blood sugar level spikes that cause damage to eyes and to other parts of the body. For this reason diabetics age more rapidly and suffer from blindness, loss of circulation in the extremities, and other problems. We can probably expect a lower glycemic index diet to reduce the incidence of some of the diseases that plague diabetics.
It is worth noting that people who eat lower glycemic index diets are typically eating more vegetables and whole grains that contain assorted beneficial compounds. So I don't think we can be certain whether the benefit reported here is totally due to the lower glycemic. However, it doesn't matter in one sense. If you eat the vegetables that lower dietary glycemic index you'll get the benefits regardless of the mechanisms of action.
Glycemic index is a scale applied to foods based on how quickly the carbohydrates in foods are converted to blood sugar, or glucose. Foods like white rice, pasta and bread are examples of foods with a high-glycemic-index, meaning that these foods are associated with a faster rise and subsequent drop in blood sugar. Whole wheat versions of rice, pasta and bread are examples of foods that have a low-glycemic-index. These foods are often considered higher quality carbohydrates because they are associated with a slower and less dramatic rise and fall of blood sugar.
Rices come in a large range of glycemic indexes. The sticky rice found in Chinese restaurants has one of the high glycemic indexes. Basmati rice is much lower and Uncle Ben's Converted Rice lower still. But grains including rice are generally higher in glycemic than beans and vegetables. If you want to eat a low glycemic index diet best to cut way back on grains and eat more beans, vegetables, and fruits.
Eating a lower glycemic index diet could probably cut your AMD risk by 20% and maybe more.
"Although carbohydrate quality was not the main focus in the AREDS, we were fortunate that the investigators had collected the dietary carbohydrate information we needed to do our analyses," says Taylor, who is also a professor at the Friedman School of Nutrition Science and Policy at Tufts and the Tufts University School of Medicine. "Our findings suggest that 20 percent of the cases of advanced AMD might have been prevented if those individuals had consumed a diet with a glycemic index below the average for their age and gender," notes Taylor.
The mechanism by which high glycemic index foods boost your risk of blindness also probably does damage in other parts of your body. So lowering your diet's average glycemic index will deliver other benefits. Plus, if you lower your glycemic index by eating more vegetables you'll benefit from vitamins and assorted other beneficial nutrients found in vegetables.
Check out David Mendosa's chart of glycemic index and glycemic load for hundreds of foods.
Update: Another way to reduce the risk of AMD: genetically engineer yourself to have genes that lower your risk of AMD.
They found that a variant in the complement C3 gene influenced the risk of developing AMD. For the 30% of the population who carry one copy of the so-called ‘fast’ variant the risk of AMD was increased by 70%, and for the 4% of people with two copies of the ‘fast’ variant the risk of AMD was more than doubled.
AMD can take two forms called ‘wet’ (also called choroidal neovascularisation or CNV) and ‘dry’ (also called geographic atrophy or GA). The ‘fast’ variant in the C3 gene increases the risk of both forms of the disease.
The complement C3 gene has a central role in the immune system. The results of this research provide strong evidence that inflammation is an important part of the disease process in AMD.
I think we are going to find that the diseases in our ancestral past selected for humans who have over-enthusiastic immune systems that cause damaging inflammation.
Free radicals and other types of reactive oxygen species (ROS) will accelerate aging if present in higher than optimal concentrations. Flavonoids in orange juice quench reactive oxygen species (ROS)
BUFFALO, N.Y. -- Orange juice, despite its high caloric load of sugars, appears to be a healthy food for diabetics due to its mother lode of flavonoids, a study by endocrinologists at the University at Buffalo has shown.
But some reactive oxygen species (ROS) are needed to carry out basic metabolic functions. So would consumption of too much flavonoids make one lethargic?
Consumption of glucose sugar boosts blood ROS. That spike in ROS is probably harmful and best avoided. So one should probably prefer foods that one can eat without getting the ROS spike.
"Many major diseases are associated with oxidative stress and inflammation in the arterial wall, so the search for foods that are least likely to cause these conditions must be pursued," said Paresh Dandona, M.D., Ph.D., head of the Diabetes-Endocrinology Center of Western New York and senior author on the study.
"Our previous work has shown that 300 calories of glucose induces ROS and other proinflammatory responses," said Dandona, who is Distinguished Professor of Medicine in the UB School of Medicine and Biomedical Sciences.
Orange juice did not boost blood ROS. But plain fructose without any flavonoids didn't boost blood ROS either.
The resulting study involved 32 healthy participants between the ages of 20 and 40, who were of normal weight, with a body mass index of 20-25 kg/m2. Participants were assigned randomly and evenly into four groups, who would drink the equivalent of 300 calories-worth of glucose, fructose, orange juice or saccharin-sweetened water.
Fasting blood samples were taken before the test and at 1, 2 and 3 hours after a 10-minute period to consume the drinks.
Results showed a significant increase in ROS within 2 hours in samples from the glucose group but not in those from the fructose, orange juice or water group.
However, two flavonoids found in orange juice inhibit ROS generation.
An additional round of test on the samples showed that neither fructose nor vitamin C suppressed the oxygen free radicals. However the two types of flavonoids in orange juice -- hesperetin and naringenin -- inhibited ROS generation by 52 percent and 77 percent, respectively.
We need orange juice that contains less fructose and more flavonoids.
More generally: We need better availability of fruits that haven't been bred to be very sweet. I always look for apple varieties that taste less sweet but which have tangier taste. Red Delicious is too sweet for my taste. I try to avoid calories while getting more beneficial compounds which have no calorie content.
Vitamins and minerals supplements aren't automatic sure wins on the health front. Too much selenium might boost the risk for the form of diabetes that makes cells resistant to the effects of insulin.
PHILADELPHIA -- A new analysis of data from a large national study found that people who took a 200 microgram selenium supplement each day for almost eight years had an increased risk of developing type 2 diabetes than those who took a placebo or dummy pill.
The data came from the Nutritional Prevention of Cancer Trial (NPC), a large randomized, multi-center, clinical trial from the eastern United States, designed to evaluate whether selenium supplements prevent skin cancer. In the study being published, researchers selected 1,202 participants who did not have diabetes when they were enrolled in the NPC Trial. Half received a 200 microgram selenium supplement and half received a placebo pill for an average of 7.7 years.
Saverio Stranges, MD, PhD, lead author of the study, says that the findings from this study suggest that selenium supplements do not prevent diabetes and that they might be harmful. “At this time, the evidence that people should take selenium supplements is extremely limited. We have observed an increased risk for diabetes over the long term in the group of participants who took selenium supplements.”
Overweight people did not experience a boost in type 2 diabetes risk from taking selenium.
In the current study, 58 out of 600 participants in the selenium group and 39 out of 602 participants in the placebo group developed type 2 diabetes. After 7.7 years of follow-up, the relative risk rate was approximately 50 percent higher among those randomly selected for the selenium group than among those randomly placed in the placebo group.
The results consistently showed higher risks of disease among participants receiving selenium across subgroups of baseline age, gender, and smoking status. However, the selenium supplements had no impact on the most overweight participants. The risk of developing diabetes tended to be higher in people who had higher blood selenium levels at the start of the study.
Whether a selenium supplement would help or hurt you probably depends on how much selenium you have in your body from your diet. People who eat Brazil nuts already are getting lots of selenium and shouldn't take a supplement.
The lack of increased risk from selenium for those who are overweight suggests that selenium works to boost type 2 diabetes by the same mechanism which fat cells boost that risk. Maybe the fat cells already flip some molecular switches to the same position selenium causes the switches to get set to and therefore when selenium comes along it can't flip the switches.
We need implanted sensors that'll tell us when we are getting too much or two little of each nutrient. We also need nutritional genomics: genetic tests that will tell us what levels of nutrients are ideal for our individual bodies.
According to the new findings, levels of the flavonoids quercetin and kaempferol were found to be on average 79 and 97 per cent higher, respectively, in organic tomatoes. Flavonoids such as these are known antioxidants and have been linked to reduced rates of cardiovascular disease, some forms of cancer and dementia, says Alyson Mitchell, a food chemist who led the research at the University of California, Davis.
The quality of tomatoes varies enormously from pale unmoist tomatoes sold in supermarkets in the winter to the best stuff from sandy acidic soil picked fully ripe in summer. Of course this stuff varies greatly in how much flavonoids it contains.
But the effect of organic farming might not apply to all organically farmed tomatoes.
That meant growers didn't need to use as much compost to keep nitrogen levels high. And without that extra boost of growth-promoting nitrogen, plants seemed to devote more energy to producing flavonoids.
The findings don't necessarily mean that all organic tomatoes would contain more flavonoids, Mitchell stressed, because soils and growing methods on different farms could vary tremendously.
My own experience with garden-grown versus farmed tomatoes is that home grown tomatoes taste much better and look more colorful than most tomatoes sold in stores.. Either soil conditions or types of tomatoes used or the ability to let the tomatoes fully ripen on the vine in gardens might account for the difference. My guess is that the tangier and more colorful tomatoes have more beneficial chemicals.
Every time I write a post about the health benefits of chocolate I eat some chocolate while writing the post. This time was no exception. How often does science tell you to do exactly what you want to do? (usually science tells you to eat vegetables you aren't excited to eat)
Eating about 30 calories a day of dark chocolate was associated with a lowering of blood pressure, without weight gain or other adverse effects, according to a study in the July 4 issue of JAMA.
Previous research has indicated that consumption of high amounts of cocoa-containing foods can lower blood pressure (BP), believed to be due to the action of the cocoa polyphenols (a group of chemical substances found in plants, some of which, such as the flavanols, are believed to be beneficial to health). “A particular concern is that the potential BP reduction contributed by the flavanols could be offset by the high sugar, fat and calorie intake with the cocoa products,” the authors write. The effect of low cocoa intake on BP is unclear.
Dirk Taubert, M.D., Ph.D., of University Hospital of Cologne, Germany, and colleagues assessed the effects of low regular amounts of cocoa on BP. The trial, conducted between January 2005 and December 2006, included 44 adults (age 56 through 73 years; 24 women, 20 men) with untreated upper-range prehypertension (BP 130/85 – 139/89) or stage 1 hypertension (BP 140/90 – 160/100). Participants were randomly assigned to receive for 18 weeks either 6.3 g (30 calories) per day of dark chocolate containing 30 mg polyphenols or matching polyphenol-free white chocolate.
That 6.3 grams of dark chocolate is about one and a third teaspoon or almost half a tablespoon of chocolate.
The researchers found that from baseline to 18 weeks, dark chocolate intake reduced average systolic BP by −2.9 (1.6) mm Hg and diastolic BP by −1.9 (1.0) mm Hg without changes in body weight, plasma levels of lipids or glucose. Hypertension prevalence declined from 86 percent to 68 percent.
The white chocolate didn't help any. You have to eat the dark stuff, the darker and less sweet the better.
A population of adults in Hawaii who averaged about 29 hours a week of sun exposure still mostly did not have an optimal amount of vitamin D in their blood.
Participants: The study population consisted of 93 adults (30 women and 63 men) with a mean (SEM) age and body mass index of 24.0 yr (0.7) and 23.6 kg/m2 (0.4), respectively. Their self-reported sun exposure was 28.9 (1.5) h/wk, yielding a calculated sun exposure index of 11.1 (0.7).
Main Outcome Measures: Serum 25(OH)D concentration was measured using a precise HPLC assay. Low vitamin D status was defined as a circulating 25(OH)D concentration less than 30 ng/ml.
Results: Mean serum 25(OH)D concentration was 31.6 ng/ml. Using a cutpoint of 30 ng/ml, 51% of this population had low vitamin D status. The highest 25(OH)D concentration was 62 ng/ml.
I wonder what their racial and age breakdown was. First off, darker skinned people will make less vitamin D from a given amount of sun exposure. Second, as skin ages it very likely becomes less efficient at harnessing sun to make vitamin D.
Another report on this study says only about 22 of those hours were without sunscreen on average. But 22 hours a week is a lot more than people get in colder climates except maybe during the summer times.
Another recent study by Paul Lips and colleagues using subjects from the Longitudinal Aging Study Amsterdam found that blood vitamin D below 20 ng/ml was associated with a more rapid decline in physical performance among the elderly.
Conclusions: Serum 25-OHD concentrations below 20 ng/ml are associated with poorer physical performance and a greater decline in physical performance in older men and women. Because almost 50% of the population had serum 25-OHD below 20 ng/ml, public health strategies should be aimed at this group.
This doesn't prove a cause and effect. It could be that sicker people get out into the sun less. Or people who get out more exercise more and therefore do a better job of maintaining muscle mass as they age.
Another study from 2005 found that even women receiving anti-osteoporosis therapy do not have enough vitamin D.
Conclusions: More than half of North American women receiving therapy to treat or prevent osteoporosis have vitamin D inadequacy, underscoring the need for improved physician and public education regarding optimization of vitamin D status in this population.
Think about what this says about doctors. These women have crumbling bones. Did the doctors prescribe vitamin D to boost their deficient blood vitamin D levels? Probably not. Yet vitamin D is essential for good bone health.
Need an excuse to eat pistachios?
DETROIT, June 11, 2007 -- Adding to a growing body of evidence, new research shows that a daily dose of pistachios may offer protective benefits against cardiovascular disease, according to a study published in the Volume 26, Number 2 issue of the Journal of the American College of Nutrition.
The study, conducted by James N. Cooper M.D., of George Mason University and Michael J. Sheridan, Sc.D., of Inova Fairfax Hospital, found that in people with moderately high cholesterol levels, a daily diet consisting of 15% of calories from pistachios (about two to three ounces or one to two handfuls of kernels) over a four-week period favorably improved some blood lipid levels.
"These results are exciting because the research indicates that adding pistachios to the daily diet can help protect the heart without a dramatic dietary lifestyle change," said Dr. James Cooper. "This research challenges the previously-held belief that a low-fat diet is best for heart health. Studies now show that a diet with a moderate amount of healthful monounsaturated fat, like the kind found in pistachios, is a more effective way to prevent heart disease than reducing overall fat intake. What's more, we noted very good compliance and a positive response from participants during the four-week period."
Nuts are good.
Different studies produce conflicting results on the question of which diet is best for weight loss. A recent study that looked insulin response to sugar consumption found that for people whose bodies produce more insulin in response to an oral glucose tolerance test the best diet is one that lowers glycemic index.
Overweight individuals who secrete insulin at a higher level may experience greater weight loss by selecting a low-glycemic load diet, compared to a low-fat diet, according to a study in the May 16 issue of JAMA. The researchers also found a low-glycemic load diet to have beneficial effects on HDL cholesterol and triglyceride concentrations.
"With prevalence approaching one-third of the population, obesity is among the most important medical problems in the United States and identification of effective dietary treatment has become a major public health priority. Three popular diets—low fat, low carbohydrate, and low glycemic load—have recently received much attention. However, clinical trials have produced inconsistent findings, with some suggesting that one diet is superior for weight loss and others indicating no difference between diets," the authors write. They add that one explanation for the inconsistent findings could relate to the inherent physiological differences among study participants. "One physiological mechanism that might relate weight loss to dietary composition is individual differences in insulin secretion."
A low glycemic index diet is one which contains carbohydrates in forms that break down slowly in the intestine.
A low glycemic index diet works best for people whose bodies secrete more insulin in response to consuming glucose.
The researchers found that change in body weight and body fat percentage did not differ between the diet groups overall. However, for those with insulin concentration at 30 minutes above the median (midpoint), the low–glycemic load diet produced a greater decrease in weight (12.8 lbs. vs. 2.6 lbs.) and body fat percentage (–2.6 percent vs. –0.9 percent) than the low-fat diet at 18 months. There were no significant differences in these end points between diet groups for those with insulin concentration at 30 minutes below the median level. Among all the participants in the study, high-density lipoprotein cholesterol (the "good" cholesterol) and triglyceride concentrations improved more on the low–glycemic load diet, whereas low-density lipoprotein cholesterol (the "bad" cholesterol) concentration improved more on the low-fat diet.
"The main finding of our study is that a simple measure of insulin secretion predicted weight and body fat loss on low–glycemic load and low-fat diets," the authors write. "For obese individuals with high insulin concentration at 30 minutes during an oral glucose tolerance test, a low–glycemic load diet may promote more weight and body fat loss than a low-fat diet. Regardless of insulin secretion, a low–glycemic load diet has beneficial effects on concentrations of HDL cholesterol and triglycerides but not on LDL cholesterol. Additional research is needed to examine these effects in other populations and to explore the mechanistic basis for the observed diet-phenotype interaction."
The big insulin response could cause more weight gain by a couple of mechanisms. First off, the greater amount of insulin causes the sugar to get cleared from the blood more rapidly. Therefore blood sugar drops and the more rapid return to a state of lower blood pressure probably brings with it hunger pangs. Second, some of the sugar that gets moved out of the blood gets converted into fat for storage. If the sugar came into the blood and exited the blood more slowly the body could probably burn more of it before it gets converted to fat.
A diet that does not much stimulate the islets of Langerhans. on your pancreas to pump out a lot of insulin in response to what you eat is probably a better diet regardless of whether you are trying to lose weight. Big blood sugar spikes cause sugar to bind in places harmful to your health and that accelerates aging. That is why diabetics have much shorter life expectancies.
If you want to lower the glycemic index of your diet then choose among foods that have low glycemic index. Here is the glycemic index for hundreds of foods. Also see David Mendosa's satiety index for foods.
Here is the research paper: Effects of a Low–Glycemic Load vs Low-Fat Diet in Obese Young Adults.
A research team at Wake Forest University Baptist Medical Center found obese old women who diet and lose weight maintain or increase their mobility.
Her study evaluated 23 obese, postmenopausal, sedentary women with a mean age of 58 who participated in the DEMO study. For five months, their meals and snacks were provided by the study and contained 400 fewer calories than they needed to maintain their weight.
Participants’ body composition and physical function were measured before and after the five-month period. Tests of physical function measured knee strength, hand-grip strength, walking speed, aerobic fitness and ability to quickly rise from a chair without using their arms. The women lost an average of 25 pounds, with muscle representing about 35 percent of the total loss.
“Despite the large amount of muscle loss, their aerobic fitness and their ability to rise from a chair showed a trend toward improvement,” said Demons. “Their strength and walking speed did not change. This suggests that their weight loss through dieting wouldn’t be expected to lead to increased disability.”
So far, so good. But the overwhelming majority of people who lose weight regain it. Well, they regained proportionately less muscle than they lost.
Lyles’ project evaluated 30 women from the DEMO study to determine body composition when weight was regained. Body composition was measured before and after the five-month period of calorie restriction. A third measurement was taken 12 months later.
The women lost an average of 25 pounds – about 32 percent of the lost weight was muscle and 68 percent was fat. The women regained an average of 11 pounds. About 27 percent of the regained weight was muscle and 73 percent was fat.
35% of their loss was muscle. But only 27% of their gain was muscle. That's not good. Some of that could be due to aging. But it seems too large a change to attribute only to aging.
I'm skeptical of the benefit of dieting for these women. Almost all of them are going to regain most or all the lost weight. Dieting might be worse than not dieting. Exercise to build up muscle mass might provide a clearer benefit. I'm skeptical that people can defeat the appetite regulation mechanism in the brain which starts telling them to eat more when they get their weight down. We need drugs that reduce appetite or for most people weight loss diets are going to do more harm than good.
Pistachio consumption lowered blood pressure and improved vascular performance.
The diets included a Step I Diet – a standard heart healthy diet with 25 percent fat and 8 percent saturated fat, a diet containing 1.5 ounces of pistachios that was a Step I Diet with 30 percent total fat and 8 percent saturated fat and a diet containing 3 ounces of pistachios that was a Step I Diet containing 34 percent fat and 8 percent saturated fat. At the end of each four-week diet regime, the researchers measured blood pressure and total peripheral vascular resistance at rest and during two stress tests.
The two tests consisted of a physical test and a psychological test. The physical test consists of putting one foot in a bucket of ice water for 2.5 minutes. The psychological test asks participants to listen to two numbers, add them in their head and say the answer. Then they hear another number and they must add it to the second number they heard, not the sum they spoke.
Note these results go against the simple rule that more fats are bad. Nuts are a more complicated story in part because their fats are less saturated.
Pistachios reduced the effects of stress on blood pressure. Stressful conditions did not increase blood pressure as much in people who were on diets that included pistachios. Pistachios caused artery relaxation.
The researchers found that both pistachio containing diets reduced the stress effects on blood pressure, but that the 1.5 ounce pistachio diet reduced systolic blood pressure by 4.8 millimeters of mercury while the 3-ounce pistachio diet only reduced systolic blood pressure by 2.4 millimeters of mercury. The diets had no effect on normal, resting blood pressure.
"When we only look at blood pressure, these results are confusing," says West. "If it is the pistachios, why is it not dose related?"
When the researchers looked at total peripheral vascular resistance, it was clear that the 3-ounce diet caused greater relaxation of arteries. Because the body tightly regulates blood pressure, rather than allowing blood pressure to drop further, the heart compensated by pumping more forcefully.
The artery benefits might come from the high concentrations of arginine found in pistachios and some other nuts. Pistachios have two and a half grams of arginine in a cup. The arginine helps boost nitric acid which relaxes arteries.
This same study found that pistachios lower the bad forms of cholesterol.
The multi-week study, which received funding from the California Pistachio Commission , concluded that three ounces of pistachios a day reduced LDL levels by 11.6 percent, total cholesterol levels by 8.4 percent, and non-high density lipoproteins (non-HDL) by 11.2 percent.
Lower cholesterol, less reaction to stress, lower blood pressure. Does the arginine story get any better? A different study by the University of Toronto’s Dr. Cyril Kendall and Dr. David Jenkins (he who developed his "ape diet" to lower cholesterol in humans) finds that pistachios reduce blood sugar rise after high carbohydrate meals.
Drs. Jenkins and Kendall and their research colleagues studied 10 healthy individuals who participated in a number of acute dietary studies over the course of two months. After an overnight fast, participants were given a one-, two- or three-ounce serving of pistachios alone or served with a slice of white bread and blood sugar levels were measured over a two-hour period. The findings suggest that consumption of pistachios with a carbohydrate-rich meal significantly lowered the d blood glucose response. As consumption of pistachios increased, the blood sugar lowering response was enhanced. In addition, when pistachios were consumed alone, the rise in blood glucose was minimal.
The researchers also monitored the effect of pistachios consumed with different common carbohydrate foods on postprandial glycemia, or blood sugar levels after eating. The addition of pistachios to a number of other commonly consumed carbohydrate-rich foods – such as mashed potatoes, pasta and rice – also resulted in significant reductions in the blood sugar response, compared to when these foods were eaten alone.
These results are consistent with a larger body of research showing health benefits from consumption of nuts. Curiously, pistachios have more carbohydrates than a lot of other nuts. Yet they provided blood sugar benefits.