Remember back a few years when you used to walk out of the medical office with recommendations to take a whole handful of vitamins? I remember emphasizing to my patients how important  it was to at least take daily doses of Vitamin C and Vitamin E for their antioxidant effects and to prevent heart disease.

Then the studies came out showing that these two vitamins did nothing to prevent heart disease, and along with this came recommendations that taking these vitamins as supplements was not necessary.

Now it appears that taking those two vitamins regularly may have some unexpected negative effects.

A recent study in the May issue of the National Academy of Science Proceedings USA (Proc Natl Acad Sci U S A 2009 May 26; 106:8665) showed that Vitamins C and E actually may block some of the beneficial effects of exercise. That’s right – you can be exercising regularly and not getting the good physiological effects of it if you are taking these vitamins.

This study should do away with what many people think: that though vitamins may not help the body, they certainly can’t hurt. Now we know that they can.

So, back to our usual mantra: discuss with your primary care clinician what supplements you really need to be taking; eat nutritiously; exercise regularly; and stop taking unnecessary vitamins!