Vitamin E, C and Exercise

A question of balance… and prejudice?  Recent publication of a research article from Germany has created lots more controversy around antioxidant supplements, though vitamin C and vitamin E were the only compounds studied, and there are a great many more antioxidants both in foods and in supplements that have not been looked at in this context.

The article, published in the on-line version of Proceedings of the National Academy of Sciences (PNAS) http://www.pnas.org/content/early/2009/05/11/0903485106 showed that 500 mg of vitamin C twice daily and 400 IU of d-alpha tocopherol (1 of the 8 forms of the vitamin E complex) taken once daily by 20 young healthy men who performed supervised exercise for 85 minutes Monday thru Friday for 4 weeks, decreased the beneficial effects that this exercise program had on insulin sensitivity in the 20 unsupplemented men (control group). What this study appears to have discovered is that the oxygen free radicals produced by exercise produce beneficial effects on glucose metabolism, and may help decrease development of diabetes. However, the title of the article “Antioxidants prevent health-promoting effects of physical exercise in humans” overstates the case quite a bit, since their findings related ONLY to insulin sensitivity, and did not at all investigate the other known benefits of exercise, such as improving cardiovascular function, immune response, stress handling, mood, cognitive function, etc. etc. There was also no detriment shown in the supplemented group

Antioxidant vitamins such as vitamin C and E are different from many of the other antioxidants found in foods, herbs, spices, and teas, in that they can become free radicals themselves, if the diet is low in antioxidants and the individuals are under high oxidative stress. The “burst” of oxygen free radicals associated with an hour of exercise are quite different from the continuous barrage of free radicals associated with smoking for instance. So this study tells us only about the effect of 2 specific vitamin antioxidants, in a group of healthy young men, in terms of markers of insulin sensitivity, 1 of many known positive benefits of exercise.

 

This is not to minimize the importance of these findings, but simply to put them in context. Unfortunately, a controversy loving and science undereducated press will generalize and draw unwarranted conclusions, and the anti-supplement folks will point and say, see we told you so—supplements are no good….

 

It is important to document that at least in this context, the oxygen free radicals generated by an hour of intensive exercise have some beneficial effects that we would be better off not to block. We don’t know if other antioxidants such as co-q-10, alpha lipoic acid, OPCs, and other polyphenolic compounds would have similar effects or not. We also don’t know if a high antioxidant diet vs a low antioxidant diet has impact on the system they studied (diet is a major confounding influence on any studies of antioxidant supplements, and notoriously difficult to control for). But its probably the case that if you’re a young healthy man who exercises, or someone with risk factors for metabolic syndrome or diabetes who exercises, its probably best not to take vitamins C and E along with your exercise.

 

In biology there is always a question of balance. Its almost always possible to have too much of a good thing, whether that be oxygen free radicals or antioxidants—having the RIGHT AMOUNT is key, which probably varies with age, sex, state of health, environment, diet, level of physical activity, etc. I would predict that if the investigators studied antioxidants (optimally a much larger number in much smaller amounts, because that is how nutrients work) in people training for marathons and triathlons, where the oxidative stress is much greater, they would find a net BENEFIT for antioxidants supplements. My rule of thumb in 35 years of experience prescribing and formulating nutritional supplements has been to use many nutrients together, and avoid megadoses of any one, as that is most likely to create imbalances. My hope is that before too many more decades scientists will develop a model to study nutritional supplements in humans as networks of many interacting compounds that support and supplement the diet to support health, rather than as a few compounds in large doses and in isolation.

 

Below are some quotes from other experts that illustrate the points I’m making (borrowed from www.nutraingredients.com)

The design of randomized clinical trials to study isolated nutrient factors, following the drug- or evidence-based model in general has received much criticism.

Andrew Shao, PhD, vice president of scientific & regulatory affairs for the Council for Responsible Nutrition (CRN), a trade association, said: “The current drug-based approach used in randomized clinical trials may not be the best approach to assess the health benefits of antioxidants, or other nutrients for that matter, and that researchers need to rethink how to design and execute such trials.”

“I do think more clinical trials are needed for antioxidants, but it is critical that they are designed and conducted to truly test the question(s) of interest, with the results interpreted and communicated appropriately,” added Dr Shao.

Jeff Blumberg, professor of nutrition science and policy at Tufts University said: “I think that when we look at  the idea of a single gold standard, like the randomized clinical trial, for evaluating nutrients, foods and diets, it  just doesn’t work.

“Sometimes it’s useful for answering for some very specific questions, but I think at other times we must go and use the approach that we have been using for the last generation or two, of looking at all of the research strategies and the information they can give us, from basic research using cell cultures and animal models, from clinical experience looking at how patients respond in the clinic, to observational studies of large populations followed for long times consuming different types of diets, as well as the intervention clinical trials.”

Understanding antioxidants

The criticisms of the drug-model for testing nutrients highlight fundamental issues with the understanding of antioxidants, and nutrients in general. Professor Blumberg added that it was important to understand how nutrients work.

“When we look at nutrients, nutrients are distributed throughout the body. Essential nutrients like vitamins and minerals have to be in every cell in every tissue in our body,” he said. “But in fact the body concentrates those nutrients in higher amounts in some tissues and in lower amounts in other tissues, it uses them in combination with other nutrients. They are designed in a system of synergies and networks.”

DHEA May Increase Bone Density In Older Women

You probably don’t hear much from your doctor about DHEA. Since it’s a naturally occurring hormone and not patentable, its become a nutritional supplement in the US (though a drug in the EU). And doctors don’t get educated about nutritional supplements, at least not much (not yet). But I’ve been paying attention to DHEA for about 15 years, and have often included it in programs for people who need to build back lost bone. The only people who shouldn’t use it are those who have or have had hormone related cancers such as estrogen receptor positive breast cancer, or prostate cancer. In this study, reported on at Science Daily, they gave both men and women between the ages of 65 and 75, 50 mg of DHEA.

Taking a DHEA supplement combined with vitamin D and calcium can significantly improve spinal bone density in older women, according to a new study from a Saint Louis University scientist and his colleagues at Washington University.

In my experience that dose is a bit high for women, about right for most men, though some need up to 100 mg to normalize their blood level. Its really best to ask your doctor to test your blood levels of both “free” (unbound) DHEA, and DHEA sulfate (its storage form). If either one is low, you’re a good candidate for supplementing this “supplement”. Your body can turn DHEA into any adrenal or sex hormone that it decides it needs—DHEA is a so-called “precursor” hormone.

They also went a little bit light on the vitamin D in this study (700 IU). Most adults who work indoors need 1000 IU of vitamin D for every 30 pounds of body weight, and 50% more than that if they are dark skinned, overweight, or obese. Again, after you’ve supplemented vitamin D for 3 or 4 months, it’s a good idea to ask your doctor to measure your blood level of 25 hydroxy vitamin D. You want it to be between 50 and 100 ng/ml (be sure its in ng/ml units, not nmoles/L units, or it needs to be between 80 and 140).

These, along with good weight bearing exercise and resistance exercise, are BASIC things that should be done in everyone before considering drugs like Fosamax, Actonel, or Boniva. You can build a lot of your bone back, no matter what the reason that you lost it in the first place. And be sure your kids and grandkids are getting enough vitamin D, calcium, magnesium and trace minerals—they’re building the bone they’ll live off for a lifetime during their teens and early 20s.

More about Vitamin D and the Flu

Finally, SOMEBODY is talking about the vitamin D—influenza connection.   Researchers see link between vitamin D, flu immunity:

–In February, researchers reported a link between vitamin D levels in the blood and upper respiratory infections in a group of nearly 19,000 people ages 12 and older.
–A 2006 review article in the journal Epidemiology of Infection laid out a detailed case for vitamin D and its protective effect against the flu.

Best thing you can do for you and your families to protect them from the flu, swine, avian, or otherwise, is to take 1,000 IU vitamin D per 30 pounds body weight (if you’re not getting summer sun exposure without sunscreen—if you are, start supplementing when the time of year comes that your shadow is taller than you are—a rule of thumb for whether or not the sun is strong enough to produce vitamin D in your skin. I predict that once studies are done, they will show that having a 25-OH vitamin D level between 50 and 100 ng/ml is better at preventing flu than any vaccine—not to mention reducing the risk of many common and deadly forms of cancer.

Vitamin D and Flu

With all the media coverage of the “swine flu” (H1N1) non-epidemic, I haven’t heard a single expert mention what could well be the most effective public health measure in preventing a pandemic—the recommendation for everyone to take enough vitamin D3 (or get enough un-blocked summer sun exposure) to get their 25-hydroxy vitamin D blood level above 50 ng/ml (but not more than 100 ng/ml). A good rule of thumb for supplementation is 1,000 IU for every 30 pounds of body weight. If your health insurance won’t cover the cost of a vitamin D test, the least expensive way ($65) to check your level is a home test kit available through the vitamin D council’s website, unless you live in NY, in which case you’ll have to get your doctor to order a blood test for you.

To read the abstract of the study about vitamin D levels and influenza visit PubMed.

Routine Removal of Ovaries During Hysterectomy May be Harmful

The advice I’ve always given women past menopause who were having hysterectomies for some good reason (it used to be simply medical fashion), has been to leave their ovaries in place—and especially so for women who haven’t yet reached menopause.   A recent study conducted by Saint John’s Health Center and reported on Reuters seems to confirms my advice.

During hysterectomy operations, surgeons often remove a woman’s ovaries as well as her uterus. But new research suggests that for women are not at high risk for ovarian cancer, removing the ovaries during hysterectomy may adversely impact long-term health.

For decades gynecologists have taken them out with the idea that after menopause ovaries no longer functioned, and were just laying around waiting for ovarian cancer to develop. Well, turns out, as it seemed reasonable to me, that ovaries DO function after menopause, they just function differently than before, making less estrogen and progesterone, but they continue to contribute to health—in fact, it would appear that they play a role in preventing heart disease, stroke, and death from many causes, including lung and other cancers.

Taking them out does indeed reduce the risk of ovarian and breast cancer, but this benefit is far outweighed by the detriment. For women who survive 35 years after hysterectomy, there is 1 premature death for every 9 cases where healthy ovaries are removed. I think its generally a good policy to assume that all the parts we arrive with on this planet have a purpose throughout life, even if we haven’t figured out yet what it is. Just because we can survive without an appendix, tonsils, or ovaries, doesn’t mean it’s a good idea to surgically remove it unless it is irreversibly damaged, infected, containing cancer, or otherwise a serious liability and beyond repair.