AREDS2 Explained by an Eye Doctor
Share
If your eye doctor has ever mentioned AREDS2 to you — or if you've seen it on the label of an eye vitamin and wondered what it actually means — this article is for you. It's one of those terms that gets thrown around a lot in eye care without much explanation. Let me change that.
What Is AREDS2?
AREDS2 stands for Age-Related Eye Disease Study 2. It was a large clinical trial conducted by the National Eye Institute, which is part of the National Institutes of Health. The study followed over 4,000 participants over a period of five years and was designed to find out whether specific nutritional supplements could slow the progression of age-related macular degeneration — AMD for short.
It was the second major study of its kind. The original AREDS study, completed in 2001, found that a specific combination of vitamins and minerals reduced the risk of advanced AMD in certain patients. AREDS2, completed in 2013, built on those findings and refined the formula — most importantly by replacing beta-carotene with lutein and zeaxanthin, which proved to be both safer and more effective.
What Did AREDS2 Find?
The results were significant. In patients with intermediate AMD, or advanced AMD in one eye, the AREDS2 supplement formula reduced the risk of progression to advanced AMD by approximately 25 percent over five years.
That is a meaningful number. Macular degeneration has no cure. There is no treatment that reverses damage already done. So a 25 percent reduction in the risk of progression — achieved through nutrition alone — is something every eye care professional takes seriously.
What Is the AREDS2 Formula?
The specific nutrient combination studied in AREDS2 consists of:
Vitamin C — 500 mg Vitamin E — 400 IU Zinc — 80 mg Copper — 2 mg Lutein — 10 mg Zeaxanthin — 2 mg
These are the amounts used in the clinical trial. When a supplement says it's "based on the AREDS2 formula" it means it contains these ingredients in roughly these amounts.
Who Is AREDS2 For?
This is one of the most important points I want to make — and one that often gets lost in the marketing around eye vitamins.
The AREDS2 study was specifically designed for people who already have AMD — either intermediate AMD or advanced AMD in one eye. The research demonstrates a clear benefit for that population.
For people who don't yet have AMD, the evidence is less definitive. The study wasn't designed to answer whether these supplements prevent AMD from developing in the first place — only whether they slow its progression once it's already present.
That doesn't mean there's no value in proactive macular nutrition for healthy eyes. Lutein and zeaxanthin play a real role in maintaining macular pigment regardless of disease status. But I want to be straightforward with you — if someone tells you AREDS2 proves these supplements prevent macular degeneration in healthy people, that's overstating what the research actually shows.
What AREDS2 Didn't Include
Here is something worth knowing. The AREDS2 formula contains lutein and zeaxanthin but does not include meso-zeaxanthin — the third carotenoid found in the macula.
The reason is timing. The AREDS2 study was designed before meso-zeaxanthin had been as extensively researched as it has been in the years since. Subsequent research has suggested that meso-zeaxanthin plays an important role in macular pigment, particularly at the very center of the retina where vision is sharpest. Research suggests that including all three macular carotenoids may support a more complete macular pigment profile than lutein and zeaxanthin alone.
This is an evolving area of science and something I follow closely as a clinician.
Should You Take an AREDS2 Supplement?
That's a conversation best had with your own eye doctor, who knows your history, your risk factors, and the current state of your retinal health. What I can tell you is this:
If you have been diagnosed with intermediate or advanced AMD in one eye, the evidence supporting an AREDS2 based supplement is strong and your eye doctor has very likely already recommended one.
If you are over 50 with a family history of macular degeneration, or if you're simply looking to support your long term macular health proactively, a supplement that includes lutein, zeaxanthin, and meso-zeaxanthin in clinically relevant amounts is a reasonable and well-informed choice.
What matters most is that whatever you choose, you take it consistently. A supplement that costs less and gets taken every day will always outperform a more expensive one that sits in the cabinet.
The Bottom Line
AREDS2 is the most important nutritional study ever conducted on eye health. Its findings — that specific nutrients can meaningfully slow the progression of macular degeneration — changed how eye doctors think about nutrition and vision. Understanding what it actually studied, what it found, and who it applies to puts you in a much better position to make informed decisions about your own eye health.
That's exactly the kind of conversation I built Eye Doctor Health around.
Dr. Brad LaVallie is a Doctor of Optometry with 28 years of clinical experience and the founder of Eye Doctor Health.