Chef Tim Says...

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Dr. Tim Says...

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Dr. Tim Says....

Exercise and Supplements

I don't write about exercise a lot because it's not my specialty. While I know a lot about it, exercise regularly myself and always talk with my patients about it, the Dr. Gourmet website is about food and nutrition. We've begun to incorporate exercise into our mission because of its importance and you'll see more info in the future on this topic.

I have, however, as part of our mission written occasionally about nutritional supplements - vitamins and such. Those of you who are regular readers know that I don't believe the research supports taking vitamins. In the past I have used the premise of "doesn't help but probably won't hurt" when it comes to vitamins. There has been some recent evidence that I've written on that indicates taking vitamins might actually be bad for you. We're a long way from knowing for sure, but this past week another study has been published that casts more doubt on the idea of "probably won't hurt." One of the medical students I work with who is very interested in exercise sent this one my way.

Michael Ristow and his colleagues in Germany discuss their findings about the protective effects of exercise for Type II diabetics in a paper published last week. They postulate that taking antioxidant supplements such as Vitamin C and Vitamin E can block the body's own ability to repair itself. They had 38 men exercise and gave half of them the vitamins. They then measured the participants’ insulin response as well as a variety of inflammatory markers during the exercise phase.

You guessed it. The group that took the vitamins had a poorer response to insulin sensitivity. They also found that the body's own system of natural antioxidants were not activated in those taking the supplements. The most interesting thing to me was that this effect occurred no matter what the participant’s previous level of physical activity and training. Even if a participant had been exercising regularly before the testing, the supplements still blocked the body's natural abilities.

Keep in mind that this is a small study (meaning that it includes few people). While the results are pretty solid, the smaller the study is, the less reliable the results. Still, this is more evidence that vitamins and supplements are not likely to be of benefit, and that alone is reason to not spend your money. It is, however, worrisome that taking vitamins might actually be bad for you.

Eat well, eat healthy, enjoy life!

Timothy S. Harlan, M.D.
Dr. Gourmet
May 18, 2009
Last updated: 05/18/09