Want to see well into old age? People with declining vision should do more than eat their vegetables.

A seven-year study of 3,600 people found that a high dose of daily antioxidants and zinc slowed progress of age-related macular degeneration, a common eye disease that can slowly blot out vision.

The formula that worked included:

Vitamin C, 500 milligrams.

Vitamin E, 400 IU.

Beta carotene, 15 milligrams.

Zinc, 80 milligrams.

Copper, 2 milligrams.

Among people who took this combination, only 20 percent progressed to advanced AMD after six years. Almost 30 percent of people taking a placebo did.

The study, conducted by the National Eye Institute (a branch of the National Institutes of Health) and published in Archives of Ophthalmology, did not find that supplements could prevent AMD in the first place.

AMD affects 10 million Americans. It is the most common cause of later-life vision loss. About one-fourth of people over age 65 have at least minor symptoms of macular degeneration.

Symptoms include distortions and blank or blurry spots in the center of vision. Spots are caused by deposits or overgrown blood vessels on a tiny section of the retina called the macula. The macula is what lets you see straight ahead, read, drive and see colors.

Before taking supplements, consult your eye doctor, said Dr. Bruce Rosenthal, chairman of AMD Alliance International in Baltimore. He also advised people with early-stage AMD to stop smoking and control high blood pressure because both can make AMD worse.