AREDS
Age-Related Eye Disease Study
Clinical trial
The Age-Related Eye Disease Study (AREDS) was a clinical trial sponsored by the National Eye Institute that ran from 1992 to 2001.[1] The study was designed to:
- investigate the natural history and risk factors of age-related macular degeneration (AMD) and cataracts, and
- evaluate the effects of high doses of antioxidants and zinc on the progression of the two conditions in those with AMD.
The results were reported in the October 2001 issue of Archives of Ophthalmology.[1] The study followed 3640 individuals for an average of 6.3 years between 1992 and 2001. The researchers concluded that high levels of antioxidants and zinc can reduce some people's risk of developing advanced AMD by about 25 percent.[1] Advanced AMD is defined as either choroidal neovascularization (wet macular degeneration) or atrophic age-related macular degeneration (geographic atrophy). The anti-oxidants and zinc supplements only reduced the risk of progression to wet macular degeneration. Those that benefited from the dietary supplements included those with intermediate-stage AMD and those with advanced AMD in one eye only. The supplements had no significant effect on the development or progression of cataracts. "High levels" in this case were defined to be:
- 500 milligrams of vitamin C;
- 400 international units of vitamin E;
- 15 milligrams of beta-carotene (or 25,000 international units of vitamin A);
- 80 milligrams of the dietary mineral zinc, in the form of zinc oxide; and
- two milligrams of copper as cupric oxide, added to prevent copper deficiency anemia, a condition associated with high levels of zinc intake.
Bausch & Lomb was a collaborator in the study.[2] They and other suppliers provide supplements pre-packaged with formulations based on this study.
Studies in 2016[3] and 2018[4] later showed that this average 25 percent reduction in risk from the combination of anti-oxidants and zinc varies by genotype.