Eat your antioxidants

People often rely on vitamin supplements to make up for their poor diets. This is especially true now that we know that some vitamins, such as antioxidants (vitamins E, C, or beta-carotene) or B vitamins, have been shown in the lab to help prevent such conditions as cancer, heart disease, and high cholesterol. But are the supplements actually having the same impact as a diet that contains more vitamins through diet alone?

In a meta-analysis of eleven studies, researchers at Johns Hopkins, the NIH, and the Instituto de Salud Carlos III, in Madrid, Spain, assessed whether taking supplements of antioxidants and B vitamins actually had any effect on the progression of atherosclerosis (heart disease) (Am J Clin Nutr 2006;84(4):880-7). The various studies had similar basic outlines: they measured the amount of plaque lining the arteries of each subject, then randomly assigned each subject to a control group (no supplementation) or a treatment group (receiving antioxidant or B-vitamin supplementation). At the end of each trial, the researchers then assessed how much the plaque formation in the arteries had increased, if at all.

The meta-analysis showed, quite simply, no evidence that supplementing one's diet with antioxidants or B vitamins had any effect on atherosclerosis. In fact, 6 fairly large trials suggested that antioxidants might actually make the progression of atherosclerosis worse, not better. Further, they seemed to reduce the positive effects of common atherosclerosis medications.

What this means for you

Scientific proof that at least in the case of heart disease, you're better off improving your diet than just taking supplements. Get more antioxidants in your diet by snacking on vegetables and fruit rather than pills.

First posted: November 8, 2006