The National Eye Institute's Age-Related Eye Disease Study (AREDS) was a hallmark research study that suggested certain nutrients appear to promote macular health while reducing the risk of age-related macular degeneration (AMD), especially in older populations. The study's findings, published in 2001, linked intake of a specific antioxidant formula -- which included high-dose servings of vitamins C and E, beta carotene, zinc and copper -- with a 25% reduction in developing age-related macular degeneration and a 19% reduction in risk of losing central vision.
The first AREDS study's success inspired the National Institutes of Health National Eye Institute (NEI) to launch a second study, dubbed AREDS2. This follow-up study investigated how additional nutrients might enhance the original AREDS formula's ability to reduce risk of AMD and vision loss.
In its AREDS 2 study, the NEI chose to focus on Omega-3 fatty acids EPA and DHA, along with botanical antioxidants lutein and zeaxanthin, which had all shown vision health-supportive promise in earlier research studies. While evaluating the macular health-supportive potential of these nutrients was the primary goal of AREDS2, the study also investigated how removing beta carotene and reducing zinc from the original AREDS combination might influence the formula's safety, tolerability and efficacy.
A large, well-designed study, AREDS2 included over 4,000 participants, aged 50-85, who all had elevated risk for developing AMD. These subjects were evaluated at 82 different clinical sites across the United States.
AREDS2 study subjects took one of four different nutritional supplements every day over the course of five years. Groups were assigned the original AREDS formula, AREDS with low zinc, AREDS with no beta carotene, or AREDS with no beta carotene and low zinc. In addition, study subjects boosted their AREDS formula with additional supplements that included 10 mg of lutein with 2 mg of zeaxanthin; 1,000 mg of omega-3 fatty acids; a combination of lutein, zeaxanthin and Omega-3 fatty acids; or placebo.
Over the course of the study, subjects' macular health was regularly evaluated with retinal photography, or by analysis of existing treatment in cases where AMD had already manifested and progressed.
The AREDS2 study concluded in 2011; final results were published in 2013. At the study's end, researchers reported that:
In response to this large-scale study, some eye vitamin manufacturers have formulated AREDS2 vitamins for macular health that are based upon the study's findings:
With results published in 2013, the AREDS2 study represents the most up-to-date research on nutritional supplements, antioxidants and macular health. The study's findings gain even more credibility due to their association with the United States National Institutes of Health (NIH) and National Eye Institute. These organizations have acknowledged that ordinary multivitamins and diet cannot supply the high-dose antioxidant servings that make AREDS and AREDS2 formulas effective in supporting eye health.
Both the NIH and NEI have suggested that people who face a higher risk of developing AMD should consider taking nutritional supplements based on AREDS and AREDS2 study findings. These organizations further suggest that those who take AREDS and AREDS2 formulas should do so under the direction of a primary care doctor or eye doctor.