The original AREDS found that high doses of antioxidants (vitamins C and E, and beta-carotene) and zinc could reduce the risk of developing advanced AMD by about 25% in individuals with intermediate or advanced stages of the disease. AREDS2 refined these findings by exploring the effects of adding omega-3 fatty acids and substituting beta-carotene with lutein and zeaxanthin. It concluded that the modified formulation without beta-carotene was equally effective and safer, especially for smokers who were at increased risk of lung cancer with beta-carotene supplementation.
