Rethinking Those Expensive Vitamin Supplements

Supplements inhibit the beneficial effects of exercise

If you exercise for fitness and take vitamin supplements, you might want to save cash now by rethinking the second part of that health regimen. Vitamin supplements are expensive, and a new study suggests that taking them inhibits certain beneficial bodily changes that result from strenuous exercise. If you’ve been needing cash advances between paychecks to finance a health and fitness routine, cutting out the supplements can get you that much closer to breaking free of a vicious payday loan cycle.

Supplements suppress the body’s natural defenses

When you exercise, your muscle cells burn sugar which releases reactive oxygen compounds –oxidants—that cause cell damage. The body reacts to the oxidants by strengthening its defenses against cellular damage and becoming more metabolically efficient.

Researchers in Boston and Germany found that when young male subjects who exercised took moderate amounts of vitamins C and E, the vitamins shut down their bodies’ natural defenses against cellular damage. As a result the subjects missed out on a key health benefit of exercise.

Supplements prevent improved insulin sensitivity

Another benefit of exercise is that it improves the body’s sensitivity to insulin. “Get more exercise” is often among the first recommendations given by doctors to diabetics and people at risk of diabetes. The researchers also measured sensitivity to insulin and found that exercise did not improve the sensitivity of the subjects who took vitamins.

“If people are trying to exercise, [supplementing with vitamins] is blocking the effects of insulin on the metabolic response,” said Dr. C. Ronald Kahn of the Joslin Diabetes Center in Boston, one of the researchers. Dr. Kahn theorized that although harmful in high doses, oxidants are beneficial in smaller doses because they activate the body’s natural defense systems.

The detrimental effect is significant

The effect of vitamins on these bodily functions “is really quite significant,”  he said.  The study suggests that the oxidants released during exercise are natural triggers for both of these responses. Vitamins, by efficiently destroying the oxidants, short-circuit the body’s natural responses to exercise.

Avoid large doses of antioxidant vitamin supplements

“If you exercise to promote health, you shouldn’t take large amounts of antioxidants,” Dr. Michael Ristow, a co-author of the study and nutritionist at the University of Jena in Germany, told The New York Times. Ristow and the other researchers recommend instead that people get their antioxidants from fruits and vegetables, which provide more moderate doses of vitamins and also contain natural micronutrients that help keep the body in balance.

Unless, of course, you’re a supplement manufacturer

Of course, whenever researchers find that nature has a better way of doing something, there is resistance from someone with money at stake. In this case, the monetary interests belongs to the Council for Responsible Nutrition, a trade association of dietary supplement manufacturers, whose spokesperson Andrew Shao said that most of the available evidence points to the opposite conclusion: that the antioxidants contained in vitamin supplements benefit health by reducing oxidative stress.