Do Antioxidants Prevent Cataracts and Age-Related Macular Degeneration?

Johns Hopkins Health Alert
Do Antioxidants Prevent Cataracts and Age-Related Macular Degeneration?

It's not just what you take out of your diet that might help your eye health, it's also what you add. New research suggests that foods rich in the antioxidants lutein and zeaxanthin (pronounced loo-tein and zee-uhzan- thin), and vitamins E and C may lower your risk of developing cataracts. Lutein- and zeaxanthin- containing foods also appear to help protect against advanced age-related macular degeneration. Here’s what the research shows.
Researchers speculate that free radicals -- molecules that damage healthy cells -- may lead to the formation of cataracts and worsening age-related macular degeneration. Antioxidants help prevent the damage free radicals cause.
Lutein and zeaxanthin. These carotenoids, the kind of antioxidants that color yellow and leafy dark green vegetables, such as kale, spinach, and carrots, are also found in the lens and retina of the eye. Data from the 10-year Women's Health Study, which began in 1993 and involves more than 35,000 women, found that those who ate almost 7 mg of lutein and zeaxanthin -- approximately the amount in one half cup of cooked spinach -- per day were 18% less likely to develop cataracts that those who ate only about 1 mg per day.
Researchers believe that this pair of antioxidants may help build and maintain the pigment layer of the retina. Another theory is that they help filter out blue light, protecting the eye from sunlight damage.
Vitamins E and C. The same investigators who reported the cataract-carotenoid findings also looked at the effect of vitamins E and C. They found that women who consumed the most vitamin E from food and supplements, about 262 mg a day -- approximately the equivalent of 3 cups of almonds -- were 14% less likely to develop cataracts than those who consumed only 4 mg a day. Several other studies have found similar results.
This study found little association between vitamin C and lowered risk of cataracts. But several other epidemiological studies, including the Nurses' Health Study and the Beaver Dam Eye Study, have found a lower risk of cataracts or cataract progression in those who took high levels of vitamin C.