Preventing Cataract - Cataract: Eye Care

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Preventing cataract

There is no sure way to avoid developing cataract. However, because of the link between UV radiation and cataract, people should always wear sunglasses, hats, or visors when outdoors. There is also some evidence that the eyes as well as the heart and brain may be affected by smoking, providing yet another good reason for smokers to quit.

There is mixed evidence that antioxidant vitamins may play a role in cataract prevention by capturing unstable molecules called free radicals; these are believed to degrade proteins in the eye's lens. Both exposure to UV radiation and the body's own metabolic processes can create tissue-damaging free radicals. A 1994 Harvard University study of 17,744 male doctors found that those who took multivitamin supplements had less risk of developing cataract and having cataract surgery. Other studies found a lower incidence of cataract among people who took vitamin A, beta carotene, and vitamin E supplements. However, the large Age-Related Eye Disease Study published in 2001 found that a high-dose supplement of vitamin C, vitamin E, beta carotene, and zinc had no effect on development of cataract. The evidence is not strong enough to recommend that everyone take antioxidant supplements, but you may want to talk to your doctor about whether supplement use is appropriate for you.

In the meantime, evidence does indicate a possible benefit from eating plenty of fruits and vegetables, which contain an abundance of antioxidant vitamins. Several studies published in 1999 found that people who ate the most foods rich in the antioxidants lutein and zeaxanthin, such as spinach and other dark green vegetables, were less likely to develop cataract than those who ate the least. These findings are suggestive, but not definitive.

Last updated:	June 19, 2007