The AREDS 2 formula is a specific combination of vitamins and minerals designed to slow the progression of age-related macular degeneration (AMD), the leading cause of vision loss in older adults. Developed through a major clinical trial funded by the National Eye Institute, the formula reduced the risk of advancing to late-stage AMD by about 25% in people who already had intermediate disease. It contains six ingredients at precise dosages and is widely available as an over-the-counter supplement.
What’s in the Formula
The AREDS 2 formula contains six ingredients, each at a specific dose per daily serving:
- Vitamin C: 250 mg
- Vitamin E: 90 mg
- Zinc: 40 mg
- Copper: 1 mg
- Lutein: 5 mg
- Zeaxanthin: 1 mg
Copper is included specifically to prevent copper-deficiency anemia, which can happen when you take high doses of zinc over time. The vitamins C and E function as antioxidants, while lutein and zeaxanthin are plant pigments that concentrate in the macula, the central part of the retina responsible for sharp, detailed vision.
How Lutein and Zeaxanthin Protect Your Eyes
Lutein and zeaxanthin are the two defining ingredients that set AREDS 2 apart from the original formula. These pigments accumulate in the macula and appear to protect it in two ways: they act as a natural filter that absorbs high-energy blue light before it can damage retinal cells, and they neutralize free radicals generated by light exposure. People who eat more lutein and zeaxanthin through foods like leafy greens and eggs tend to have lower rates of advanced AMD, which is what prompted researchers to test them in supplement form.
In the AREDS2 trial, participants who took lutein and zeaxanthin instead of beta-carotene had an 18% lower risk of progressing to advanced AMD. Among those whose diets were already lowest in these pigments, the benefit was even larger: a 26% lower risk compared to participants taking the original formula.
Why Beta-Carotene Was Removed
The original AREDS formula, published in 2001, used beta-carotene as its primary antioxidant. Two large cancer-prevention trials later revealed that beta-carotene supplements increase the risk of lung cancer in smokers. The AREDS trial itself confirmed this concern: former smokers who took the beta-carotene version had a higher incidence of lung cancer.
The AREDS2 trial, which ran from 2006 to 2012, tested whether lutein and zeaxanthin could replace beta-carotene without sacrificing eye protection. The results were clear. At the 10-year follow-up, participants randomly assigned to beta-carotene had nearly double the odds of developing lung cancer compared to those who received lutein and zeaxanthin. The lutein/zeaxanthin group showed no increased lung cancer risk at all, and their AMD outcomes were equal or better. That made the switch permanent. The current AREDS 2 formula is considered safe for smokers, former smokers, and nonsmokers alike.
Who Should Take It
The formula is specifically recommended for people with intermediate AMD in one or both eyes, or those who have advanced AMD in one eye but not yet in the other. These are the groups that showed a meaningful benefit in the clinical trials. The American Academy of Ophthalmology’s 2024 guidelines reflect this same recommendation.
If you have no AMD, early-stage AMD, or are simply concerned because of family history, the evidence does not support taking the formula. The AREDS2 trial excluded people without AMD or with only early disease because earlier data had already shown no benefit for those groups. This is not a general eye-health supplement or a preventive measure for people with healthy retinas.
The Zinc Question
Zinc dosage has been one of the more debated aspects of the formula. The original AREDS formula used 80 mg of zinc daily, which is well above the recommended daily amount and high enough to cause side effects. These can include stomach irritation, nausea, and more frequent urinary tract infections. Long-term use of 75 mg or more per day has also been linked to adverse cholesterol changes and impaired immune function.
The AREDS2 trial tested whether cutting zinc from 80 mg to 25 mg would reduce these side effects without losing the protective benefit. Reducing the dose had no significant effect on AMD progression, meaning the lower dose appeared to work just as well. However, the study’s lead investigators noted that the data still don’t make clear exactly how much zinc is optimal. Most commercially available AREDS 2 supplements now use either 25 mg or 40 mg of zinc, both lower than the original 80 mg. The copper in the formula remains important at any zinc dose above the daily recommended amount.
What to Know Before Buying
AREDS 2 supplements are sold over the counter by multiple manufacturers. Look for products that match the exact ingredient list and dosages from the trial rather than formulas that add extra ingredients like omega-3 fatty acids, bilberry, or other botanicals. The AREDS2 trial tested omega-3 supplementation alongside the core formula and found no additional benefit for AMD progression.
Some brands sell formulations requiring two softgels per day to reach the full dose, while others pack everything into a single pill. Check the label to confirm whether the listed amounts are per serving or per capsule, since these aren’t always the same thing. The fat-soluble ingredients (vitamin E, lutein, zeaxanthin) absorb better when taken with a meal that contains some dietary fat.