Harvard Men's Health Watch

Do multivitamins protect you from disease?

Multivitamins may slightly reduce the risk of cancer but don't prevent heart disease. Keep the focus on diet, not supplements.

Up to half of all adults in the United States may already take a multivitamin. Most probably expect it to make them feel better and prevent common illnesses, even though the evidence has always been a little sketchy. Is the one-a-day multivitamin habit truly healthful—or just wishful thinking?

The Harvard-led Physicians Health Study II (PHS II) recently found that taking a multivitamin slightly lowers the risk of being diagnosed with cancer. But if you take a multivitamin already or plan to, don't let it distract you from eating a varied and nutritious diet. "The studies of taking vitamins to prevent disease have been largely disappointing," says Dr. William Kormos, editor in chief of Harvard Men's Health Watch and a primary care physician at Harvard-affiliated Massachusetts General Hospital. "It does not appear that a multivitamin can replace a healthy diet high in fruits and vegetables."

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