More than half of American adults take vitamin and mineral supplements. If you're one of them, you may have been alarmed by headlines suggesting that antioxidant supplements containing vitamins A, E, and beta-carotene shorten your life span. Don't give up on your pills just yet. In 2007, researchers from Copenhagen published an analysis of 68 supplement studies in the Journal of the American Medical Association. They concluded that these antioxidants did little to extend life, and some of the vitamins could actually shorten it. "But nowhere in the study did it say how people died," says Jeffrey Blumberg, PhD, director of the Antioxidants Research Laboratory at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University in Boston. "That research looked at all-cause mortality, which means if you died of a homicide or in a car accident—or anything else—and you were a participant in this study, it would count." The deaths may have had nothing whatsoever to do with supplement habits.

Meir Stampfer, MD, a professor of epidemiology and nutrition at the Harvard School of Public Health in Boston, also believes the research was flawed. "It combined results from very disparate studies, including many that were short and that varied the dose of the vitamin," Stampfer says. And the dosages reviewed were extremely high. On average, study participants swallowed 20,219 IUs of vitamin A—nearly ten times the official daily recommendation; the vitamin C group took almost seven times as much.

So what's a health-conscious, supplement-swallowing woman to do? "You shouldn't make lifestyle decisions based on the research du jour," Blumberg emphasizes. "Listen to experts who consider the entire body of research." He and Stampfer both believe that most women need nothing more than a daily multivitamin and a calcium-plus-vitamin-D supplement. Though healthy foods like fruit, veggies, beans, low-fat dairy, and whole grains should be your primary source of nutrients, Americans often fail to get recommended amounts of many essential vitamins and minerals. The multivitamin will ensure that you do. "These supplements are affordable and effective," Blumberg says. "They reduce your risk for osteoporosis and for birth defects in infants—huge benefits for pennies a day."

From the September 2007 issue of O, The Oprah Magazine

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