Women can reduce their risk of early-onset cataracts by making sure they get plenty of vitamin C, new research suggests.

NEW YORK (Reuters Health)  Fri Feb 22, 5:29 PM ET

Cataracts occur when the lens of the eye becomes cloudy, and are common among people aged 75 and older. Good nutrition appears to help protect against cataracts, Dr. Allen C. Taylor of Tufts University and colleagues note, but there is little research on the link between two particular types of cataract and nutrition. They report their findings on nutrition and cortical and posterior subcapsular cataracts (PSC) in the March issue of the American Journal of Clinical Nutrition.

In cortical cataracts, cloudiness affects the central external lens of the eye, while posterior subcapsular cataracts are the most disabling visually.

The Boston researchers collected data on 492 women aged 53 to 73. None were diabetic, and none had been diagnosed with cataracts. Among the 984 eyes examined, about 34% had cortical cataracts and nearly 13% had PSCs.

Women under 60 years with daily vitamin C intakes of 362 milligrams (mg) or more had a 57% lower risk of developing cortical cataracts than their peers who consumed less than 140 mg of the vitamin a day, the researchers found.

Women who took vitamin C supplements for 10 years or more reduced their risk of developing cortical cataracts by 60%, compared with women who did not take vitamin C supplements, Taylor’s team notes.

In women who had never smoked, those who consumed more folate and carotenoids were considerably less likely to have PSCs. Carotenoids are red, yellow and orange pigments found in fruits and vegetables, which the body converts to vitamin A.

Taylor and colleagues conclude that “these data add more weight to the accumulating evidence that antioxidant nutrients can be exploited to alter the rates of development of these major (but less studied) forms of age-related opacities.” The findings also indirectly suggest, they add, that antioxidant nutrients like vitamin C can blunt smoking’s ill effects.

SOURCE: American Journal of Clinical Nutrition 2002;75:540-549.