As reported yesterday in the New York Times in an article entitled,"Vitamins Found to Curb Exercise Benefits," a recent study seems to indicate that taking supplements may be working against the benefits of exercise. I quot the meat of the article:
“If you exercise to promote health, you shouldn’t take large amounts of antioxidants,” Dr. Ristow said. A second message of the study, he said, “is that antioxidants in general cause certain effects that inhibit otherwise positive effects of exercise, dieting and other interventions.”
The effect of vitamins on exercise and glucose metabolism “is really quite significant,” said Dr. C. Ronald Kahn of the Joslin Diabetes Center in Boston, a co-author of the report. “If people are trying to exercise, this is blocking the effects of insulin on the metabolic response.”The advice does not apply to fruits and vegetables, Dr. Ristow said; even though they are high in antioxidants, the many other substances they contain presumably outweigh any negative effect.
I find it ironic that the biggest advocates of dietary supplements tend to be those people most concerned about their health who are eating proper diets. I think they view vitamins as a form of insurance. They aren't sure whether they're getting what they need, so better pop some vitamins to make sure. This "insurance" view contrasts with my "medicinal" view of only taking vitamins if there is a known deficiency you are trying to correct.
It now looks like many vitamin supplements, as opposed to being unnecessary insurance, are actually working against the training effect. By avoiding unnecessary vitamins, our workouts may be more effective. So, you may want to clean out those cabinets this weekend. Be sure to have an apple, orange or banana while you toss out supplements.