Consumers with signs of an early stage of a disease that is the most common cause of blindness in old age can slow down, or in some cases prevent, loss of vision by regularly taking a combination of three antioxidant vitamins and zinc. American researchers have spent six years looking at the age-related macular degeneration (AMD) and gathering evidence on the impact of multivitamins and zinc. The study followed 3,640 people affected by AMD, between the ages of 55 and 80, who were randomly assigned to take a daily dose of zinc supplements; antioxidants consisting of vitamin C, vitamin E and beta carotene; both zinc and antioxidants; or a placebo.