Age-related macular degeneration (AMD) is the leading cause of blindness in people over the age of 55. Two large studies sponsored by the National Eye Institute (NEI), AREDS and AREDS 2, researched using antioxidants and zinc to lower the risk of progression to advanced AMD. The 2001 AREDS study showed that high doses of antioxidants and zinc may help slow the progression of age-related macular degeneration by 25%. The 2013 AREDS 2 study suggested that omitting beta-carotene, and adding lutein and zeaxanthin, can lower the risk of progression to advanced AMD by an additional 18% compared to those AREDS 2 participants taking the AREDS formula. AREDS 2 also showed that when lowering the dose of zinc there was "no statistically significant effect on progression to advanced AMD." Viteyes AREDS 2 formulas are based on the AREDS 2 study. Viteyes eye health supplements conform to the strictest manufacturing regulations and are manufactured in the USA.