Age-related macular degeneration, or AMD, is one of the main causes of vision losses in people over age 60 in the United States, according to the National Eye Institute. Leakage of fluid under the retina by the macula, the central point of vision on the retina, causes AMD. If you have AMD, your central vision may be blurry, wavy or completely blacked out. Zinc, a mineral that acts as an antioxidant, can help prevent dry AMD, the less severe form of disease, from turning into the more serious wet form when combined with other antioxidants.
Purpose
The purpose of taking zinc and other antioxidants is to reduce or prevent further damage to the macula of the eye. Once wet macular degeneration develops, regaining lost vision is difficult, although treatments can slow the progression and, in some cases, stabilize or even improve vision.
Method
In addition to 80 mg of zinc oxide, the AREDS formula consists of 500 mg of vitamin C, 400 mg of vitamin E, 15 mg of beta-carotene, also labeled as 25,000 IU of vitamin A, and 2 mg of copper. The copper is added to offset the high levels of zinc, which can cause copper deficiency, the NEI explains. Regular daily vitamin supplements contain much lower amounts of these nutrients. Taking the supplements, available over-the-counter daily by mouth helps reduce the risk of developing AMD if you have advanced dry AMD or wet AMD in one eye but not the other.
Mechanism
Antioxidants, including zinc oxide, help slow the progression of AMD by balancing and neutralizing free radicals, unstable electrons that occur as a result of oxidation, a normal chemical reaction, in the body, WebRN explains. Free radicals can damage cells in the macula.
Benefits
Zinc, when combined with other specific antioxidants such as beta-carotene, vitamin C and vitamin E, can reduce the risk of developing wet AMD in people with dry AMD by about 25 percent, according to All About Vision. The NEI AREDS, which followed over 3,600 people for more than six years, studied a specific formulation called the AREDS formula. The study found that people with the advanced dry form of the disease or with one eye already wet decreased their chance of developing wet AMD in the other eye from 28 to 20 percent over a five-year period by taking the AREDS formula as compared to those taking a placebo. Delaying the onset of vision loss helps you stay independent longer as well as improving vision over that time period.
Considerations
Zinc and other antioxidants don't cure macular degeneration, but they do slow its progression. With further research comes the possibility of finding a cure before the disease advances. There are caveats to taking antioxidants for macular degeneration, however. High doses of zinc can cause problems in some people, the University of Maryland Medical Center reports. If you smoke, you should not take the AREDS formula that contains beta-carotene, which has been found to increase the risk of developing lung cancer in smokers. A special formula without beta-carotene is available. Taking high doses of vitamin E is also controversial, so always discuss taking an AREDS vitamin or any other medication with medical personnel who know your medical history before starting the supplement.
