Bienvenido V. Castillo, Jr., M.D.

Consumers may have noticed that there are a variety of vitamins currently being sold specifically targeted for the eyes. They usually contain beta carotene, vitamin C, vitamin E, zinc or lutein. These "eye vitamins" have become popular since a National Eye Institute study known as AREDS (Age-Related Eye Disease Study) showed that a combination of anti-oxidants and zinc lower the risk of progression of age-related macular degeneration (AMD).

Age-related macular degeneration is one of the leading causes of blindness in the United States affecting 1.7 million people, usually individuals 65 years or older. Other risk factors include Caucasian race, family history of AMD, and cigarette smoking. The exact cause of AMD is not known, but patients develop drusen which are seen as white deposits underneath the retina. As AMD progresses, the size and number of drusen increases. Loss of pigmented cells underneath the retina may occur, and new vessels may form underneath the retina. It is bleeding from these new vessels that cause sudden loss of vision from AMD.

The Age-Related Eye Disease Study began in the 1990s to determine whether high doses of anti-oxidants and zinc could decrease the risk of progression of AMD. The results of the study showed that a combination of anti-oxidants and zinc provided the best protection and reduced the risk of developing advanced AMD by 25% and loss of central vision by 19% in high risk individuals. High risk patients were those that had many medium sized drusen or a large drusen in one or both eyes (Intermediate AMD) or had already lost vision from AMD in one eye (Advanced AMD). Patients who had early AMD did not benefit from anti-oxidants or zinc treatment.

Other nutritional supplements which are thought to be good for the eyes include lutein, zeaxanthin and omega-3 fatty acids. Lutein and zeaxanthin are carotenoids found in yellow and orange fruits as well as green leafy vegetables. Omega-3 fatty acids are commonly found in fish oil such as salmon and sardines. AREDS 2 is currently underway to determine the effects of these compounds on AMD and cataracts.

Eye vitamins are generally safe, but there are some possible side effects. Urinary tract infection can occur with high doses of zinc. Copper also needs to be supplemented with zinc to prevent copper deficiency anemia. Smokers should avoid high doses of beta-carotene due to risk of cancer. Although there has been concern regarding high doses of vitamin E, the dose used for AREDS has not been associated with increased mortality.

Different brands have different combinations and doses of vitamins, and they may not be equivalent to the formula used in AREDS which is 15 mg beta-carotene, 500 mg vitamin C, and 400 I.U. vitamin E, 80 mg zinc oxide, and 2 mg cupric oxide. It is important for consumers to compare the eye vitamins they are purchasing with AREDS and to be careful about overdosing if they are already taking multivitamin supplements.

For these reasons, consumers should consult with their ophthalmologists prior to taking these eye vitamins to determine if they would benefit from treatment and what supplements they should take.

For more information on AREDS and AMD, visit the following websites:

The National Eye Institute:
www.nei.nih.gov/amd

The American Academy of Ophthalmology:
www.aao.org/public/eyehealthtopics.cfm.