In the Age-Related Eye Disease Study (AREDS) involving nearly 5,000 people, researchers found a 25 percent lower risk of developing advanced stages of AMD when a nutritional formula including vitamin E was taken. The AREDS supplement included 400 International Units (IU) of vitamin E, as well as high levels of vitamin A (as beta-carotene), vitamin C and zinc.
Based on AREDS and other nutritional studies, many eye doctors recommend that their patients supplement their diet with a daily multivitamin that contains up to 400 IU of vitamin E in combination with other antioxidants as part of their preventative eye care.
Some studies suggest vitamin E also may play a role in preventing cataracts:
In a large, long-term study of more than 3,000 adults (ages 43 to 86) in Wisconsin, five-year risk for cataracts was 60 percent lower among people who reported using multivitamins or any supplement containing vitamin E or vitamin C for more than 10 years, compared with nonusers.
In a 2008 study that evaluated the dietary intake of more than 35,000 female health professionals, women whose diets (including supplements) had the highest levels of lutein and vitamin E had a lower relative risk of cataracts than women whose diets were in the lowest 20 percent for levels of these nutrients.
However, other studies provide conflicting findings and some eye doctors say more research is required before a clear conclusion can be reached.