Age-related Macular Degeneration (AMD)

A dietary supplement of high levels of antioxidants and zinc significantly reduces the risk of advanced age-related macular degeneration (AMD) and its associated vision loss.

October 2001 issue of Archives of Ophthalmology.

Scientists found that people at high risk of developing advanced stages of AMD, a leading cause of vision loss, lowered their risk by about 25 percent when treated with a high-dose combination of vitamin C, vitamin E, beta-carotene, and zinc.

In the same high risk group — which includes people with intermediate AMD, or advanced AMD in one eye but not the other eye — the supplements reduced the risk of vision loss caused by advanced AMD by about 19 percent.

The clinical trial — called the Age-Related Eye Disease

Study (AREDS) — was sponsored by the National Eye Institute (NEI), one of the

Federal government’s National Institutes of Health.

"This is an exciting discovery because, for people at high risk for developing advanced AMD, these dietary supplements are the first effective treatment to slow the progression of the disease," said Paul A. Sieving, M.D., Ph.D., director of the NEI. "AMD is a leading cause of visual impairment and blindness in Americans 65 years of age and older.

Currently, treatment for advanced AMD is quite limited. These supplements will delay the progression to advanced AMD in people who are at high risk — those with intermediate AMD in one or both eyes,

or those with advanced AMD in one eye already

The supplements evaluated by the AREDS researchers contained 500 mg of vitamin C; 400 IU of vitamin E; 15 mg of beta-carotene; 80 mg of zinc as zinc oxide; and two mg of copper as cupric oxide (Copper was added to the AREDS formulations containing zinc to prevent copper deficiency, which may be associated with high levels of zinc supplementation).

"Previous studies have suggested that people who have diets rich in green, leafy

vegetables have a lower risk of developing AMD," said Frederick Ferris, MD,

director of clinical research at the NEI and chairman of the AREDS. "However,

the high levels of dietary supplements that were evaluated in the AREDS are very

difficult to achieve from diet alone.

"Almost two-thirds of AREDS participants chose to take a daily multivitamin in addition to their assigned study treatment," Dr. Ferris said. "The AREDS also showed that, even with a daily multivitamin, people at high risk for developing advanced AMD can lower the risk of vision loss by adding a dietary supplement with the same high levels of antioxidants and zinc used in the study."

The Age-Related Eye Disease Study involved 4,757 participants, 55-80 years of

age, in 11 clinical centers nationwide. Participants in the study were given one

of four treatments: 1) zinc alone; 2) antioxidants alone; 3) a combination of

antioxidants and zinc; or 4) a placebo, a harmless substance that has no medical

effect. The benefits of the dietary supplements were seen only in people who

began the study at high risk for developing advanced AMD — those with

intermediate AMD, and those with advanced AMD in one eye only. In this group,

those taking "antioxidants plus zinc" had the lowest risk of developing advanced

stages of AMD and its accompanying visual loss. Those in the "zinc alone" or

"antioxidant alone" groups also reduced their risk of developing advanced AMD,

but at more moderate rates compared to the "antioxidants plus zinc" group. Those

in the placebo group had the highest risk of developing advanced AMD.

Dr. Ferris said some people with intermediate AMD may not wish to take large

doses of