Findings from a recent literature review published in the American Journal of Ophthalmology synthesized decades of data on how diet and oral micronutrient supplementation affect the trajectory of age-related macular degeneration (AMD).
The authors converted this data into stage-specific guidance eye care providers can use when counseling patients during clinic visits.
Give me some background first.
AMD is a leading cause of irreversible central vision loss in older adults in high-income countries, and management options to slow progression remain limited.
Outside of effective treatments for neovascular AMD, no treatment is approved to slow progression from early to intermediate AMD—or from intermediate disease to geographic atrophy (GA).
And why does that matter?
Modifiable lifestyle factors carry real weight. Smoking remains the most clearly established modifiable risk factor, and diet has emerged as one of the strongest levers available.
Some context: Among dietary patterns studied across aging and chronic disease, the Mediterranean diet has the most consistent track record for favorable outcomes.
- Its emphasis: vegetables, whole fruits, legumes, nuts, whole grains, extra-virgin olive oil, moderate fish intake, low red meat, and minimal refined sugar.
Now, talk about the study.
A team of investigators at the National Eye Institute (NEI) and the University of Michigan ran a focused literature review on the associations between diet, oral micronutrient supplementation, and AMD progression.
The question: What, exactly, should patients with AMD eat at each stage of disease?
Who was included in the study?
The review synthesized data primarily from the Age-Related Eye Disease Studies (AREDS and AREDS2) in the United States, plus major European and North American epidemiologic and cohort studies.
To refresh: AREDS and AREDS2 followed large numbers of participants with a wide range of AMD severity over many years, tracked progression with reading center grading, and randomized participants to different micronutrient formulations.
- Worth noting: Adherence to the Mediterranean diet was quantified using the Alternative Mediterranean Diet Index (aMED), which scores intake of whole fruits, vegetables, whole grains, nuts, legumes, red meat, fish, monounsaturated fatty acid to saturated fatty acid (MUFA:SFA) ratio, and alcohol.
And the findings?
Across disease stages, closer adherence to a Mediterranean diet was consistently associated with substantially slower AMD progression.
Early AMD: Eyes without large drusen at baseline were 21% less likely to develop large drusen for participants in the highest aMED tertile compared to the lowest. A dose-response association was present throughout.
Intermediate AMD: Eyes without late AMD were 23% less likely to develop late AMD over time for participants in the top aMED tertile vs the bottom. The protective effect was stronger for progression to GA (29% decreased risk) than for neovascular AMD (16% decreased risk).
GA: Mean GA enlargement was approximately 15% slower for participants in the highest aMED tertile vs the lowest. For extrafoveal GA progressing toward the fovea, the rate was about 30% slower for the top tertile.
Tell me more.
Drilling into individual food components revealed which parts of the Mediterranean pattern were doing the heavy lifting at each stage.
For intermediate AMD: Fish intake was the strongest protective component. Eyes of participants in the top fish-intake quartile had a 31% decreased risk of progression to late AMD, with consistent dose-response associations. Higher vegetable intake came with a 23% decreased risk, while higher red meat intake carried a 20% increased risk.
For GA enlargement: Whole fruit and red meat were the standouts. Higher fruit intake was associated with a 22% slower enlargement rate, and lower red meat intake with a 23% slower rate.
- Higher MUFA:SFA ratio and avoiding heavy alcohol consumption also slowed enlargement. Fish intake did not significantly modulate GA expansion at this stage.
For GA approaching the fovea: Vegetable intake mattered most. Higher vegetable intake was associated with 40 to 50% slower progression toward the fovea for the top quartiles vs the bottom, accompanied by slower visual acuity decline.
How about when patients were on supplements?
The AREDS2 formulation (vitamin C, vitamin E, zinc, copper, and lutein/zeaxanthin) decreased the risk of progression to advanced AMD in patients with intermediate AMD or GA in at least one eye, with the benefit driven largely by reduced neovascular AMD risk.
- For extrafoveal GA, AREDS2 supplements slowed progression toward the fovea by approximately 50%.
Why that matters: Diet and supplements appear to work through complementary mechanisms. Supplements preferentially decrease neovascular AMD risk, while Mediterranean diet adherence preferentially slows GA progression. To cover both subtypes, both strategies are needed.
Any limitations?
The review was selective rather than exhaustive, and the underlying evidence base was mostly observational.
Further: Several promising areas of inquiry, including caloric restriction, intermittent fasting, and gut microbiome modulation, were excluded because current evidence is too thin for clinical guidance.
Other considerations:
- Many of the GA supplement findings came from post-hoc analyses of AREDS and AREDS2 data, not from dedicated trials
- AREDS and AREDS2 populations had healthier diets than the general U.S. population, which may have understated the impact of supplementation in less-adherent patients
- Most data came from North American and European populations, though similar protective associations have been reported for Asian and Japanese dietary patterns characterized by varied staple foods
Expert opinion?
The authors argued that the Mediterranean diet should be understood as an evidence-based template rather than a uniquely Mediterranean prescription. Patients from different cultural backgrounds can apply the same principles within their own traditional eating patterns.
Their position: Even moderate dietary changes can produce meaningful benefit because dose-response associations are present throughout the data. Perfect adoption is not required.
Anything else?
One finding that stands out: A Mediterranean diet appears to be protective even in patients with high genetic risk for AMD.
- The data: AREDS analyses found that a healthy lifestyle (no smoking, body mass index below 25, lower calorie intake, and higher intake of green leafy vegetables and fish) conferred a 3 to 5-fold decreased risk of progression to late AMD compared to an unhealthy lifestyle, even in those with high genetic risk.
Also of interest: Real-world adherence to these patterns is low.
- In the population-based Rotterdam Study, only 4% of adults met the recommended intake quantities for vegetables, fruit, and fish combined.
- The authors flagged the gap between guidelines and actual practice as a meaningful opportunity for clinicians during "teachable moments," like a new AMD diagnosis.
And lastly: the take home.
Patients with AMD at any stage should adopt a Mediterranean-style diet (or apply its principles within their own cultural eating patterns), with the specific emphasis shifting by stage.
As such: High fish intake matters most for intermediate AMD, while abundant fruit and vegetable intake plus lower red meat consumption matter most for GA.
AREDS2 supplements remain a core part of care for intermediate or advanced AMD, especially for extrafoveal GA, and work alongside, not instead of, dietary change.