David L. Katz, MD
Photo: Mackenzie Stroh
Q: You've mentioned that vitamins don't seem to guard against cancer or heart disease. But I've read that supplements can protect sight and hearing. What do you think?
— Melodi Donahue, Fairfield, California

A: A study called AREDS—the Age-Related Eye Disease Study (sponsored by the National Institutes of Health)—has generated convincing evidence that nutrient supplements can slow the progression of age-related macular degeneration (AMD), the leading cause of severe vision loss in people over 60 in the United States. The specific formula studied was a daily combination of vitamin C (500 mg), vitamin E (400 IU), beta-carotene (15 mg), zinc (80 mg), and copper (2 mg). These nutrients may also help prevent the onset of AMD, although evidence for this has yet to be shown. Other nutrients thought to offer vision protection are carotenoids such as lutein and zeaxanthin, found in brightly colored fruits and vegetables, and flavonoid antioxidants, found in fruits, tea, cocoa, and red wine, among other sources. There are indications that vitamins B2 and E may help protect against cataracts. There is also evidence that suggests omega-3 fatty acids can be helpful in inhibiting AMD and possibly cataracts.

As for hearing, the science, though less developed, suggests that folate, vitamin B12, and magnesium may be protective. Of course, the biggest danger where hearing is concerned is loud noise; avoid it when you can, and use ear protection when you can't. Similarly, if you really want to preserve your eyes—in particular the lens and retina—wear eyewear that blocks UV light.

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David L. Katz, MD, is director of the Yale-Griffin Prevention Research Center and president of the nonprofit Turn the Tide Foundation.