Good nutrition is essential to eye health, as it is to the health of all our organs. But don’t take dietary supplements claiming to “support,” “protect,” or “promote” eye health in hopes of preventing age-related macular degeneration (AMD) or cataracts—or for general eye health. There’s no evidence that any supplement can do that, contrary to what the labels and ads may imply. For instance, a 2017 Cochrane Review concluded that taking vitamin E or beta carotene supplements will not prevent or delay the onset of AMD.
Zinc, too, is essential to good vision, but supplements have not been shown to prevent vision loss. Herbal supplements, such as bilberry, often combined with high doses of vitamins, have never been shown to protect against disease or improve vision.
The only substantiated supplement claim is that the formula used in the Age-Related Eye Disease Study, known as AREDS—and the slightly different formula used in the follow-up study, AREDS2—can reduce progression of AMD in people who have an intermediate stage of the disease or a severe stage in one eye. The formula had no effect on the development or progression of cataracts.
The landmark original study, conducted by the NIH’s National Eye Institute and published in 2002, involved more than 3,600 people ages 55 to 80, followed for six years. All were at high risk for AMD-related blindness: all had at least some symptoms; some had advanced disease in one or both eyes. Researchers tested high doses of vitamins C and E, beta carotene, and zinc.
The AREDS2 study, published in 2013, tested whether the original AREDS formula could be improved by adding omega-3 fatty acids; adding lutein and zeaxanthin; removing beta carotene; or reducing zinc. This study involved more than 4,000 people ages 50 to 85 who had intermediate AMD and were at high risk for developing the advanced disease. It found that adding omega-3s did not improve the results of the original formula. Moreover, removing the beta carotene did not reduce the benefit. That’s good news, since the study found that the risk of lung cancer doubled in people who took the formula containing beta carotene, mostly in former smokers. (Current smokers were excluded from the study out of concern about this.) The formula with less zinc was just as effective as the original high-dose formula. And overall, lutein/zeaxanthin didn’t help, except when these compounds replaced beta carotene or when participants had low dietary intakes of these carotenoids.
Bottom line: If you have AMD, your eye-care professional has probably talked with you about AREDS and AREDS2 supplements. Bausch & Lomb holds the patent for both AREDS formulas (marketed as PreserVision), but there are copycat products that may not contain the correct amounts of the ingredients. This array of products can be confusing, so ask your doctor for specific guidance.