Dry macular degeneration is a gradual breakdown of the macula, the small central area of the retina responsible for sharp, detailed vision. It accounts for 85% to 90% of all age-related macular degeneration (AMD) cases and typically progresses slowly over years. Unlike the “wet” form, which involves abnormal blood vessel growth, dry AMD results from the thinning and deterioration of retinal tissue itself.
What Happens Inside the Eye
The retina sits at the back of your eye, and just beneath it lies a single layer of cells called the retinal pigment epithelium (RPE). These cells nourish the light-sensing photoreceptors above them and clear away waste products below. Between the RPE and the blood supply underneath sits a thin barrier called Bruch’s membrane, which acts as a filter for nutrients and waste moving in both directions.
With age, lipids and proteins accumulate in Bruch’s membrane, thickening it. This buildup slows the flow of nutrients to the RPE and traps waste that would normally be cleared away. The trapped material clumps into small yellow deposits called drusen, which are visible during an eye exam and serve as the hallmark sign of dry AMD. Drusen physically displace the RPE cells above them and further choke off nutrient exchange, creating a cycle of worsening stress on the tissue.
Oxidative damage from aging (and from smoking, in particular) accelerates this process by causing a waste pigment called lipofuscin to build up inside RPE cells. Lipofuscin interferes with the cells’ ability to recycle their own components and manage cholesterol. Over time, patches of RPE cells die off. When large, continuous areas of RPE are lost, the photoreceptors above them die too. This advanced stage is called geographic atrophy, named because the patches of dead tissue on imaging resemble countries on a map.
Stages and How They’re Classified
Eye specialists classify dry AMD into three stages based on the size of drusen and the condition of the RPE:
- Early AMD: Medium-sized drusen (roughly the width of a thick human hair) are present, but there are no pigment changes in the retina. Most people at this stage have no noticeable vision loss.
- Intermediate AMD: Large drusen are present, or there are visible pigment changes alongside at least medium drusen. Some people begin to notice subtle blurriness or need more light for reading.
- Late (advanced) AMD: Geographic atrophy has developed, meaning significant patches of retina have been lost. This is the stage where central vision loss becomes pronounced.
Progression between stages can take years or even decades, and not everyone who develops early AMD will advance to geographic atrophy.
Symptoms and What They Feel Like
Dry AMD develops gradually and without pain. In the early stages, you may not notice anything at all. As it progresses, common symptoms include needing brighter light for reading or close-up tasks, increased blurriness of printed text, and difficulty adjusting to dim environments like a restaurant or movie theater.
More distinctive symptoms appear as the disease advances. Straight lines may start to look bent or wavy. You might notice a blurry or blank spot near the center of your vision. Recognizing faces becomes harder, and fine details get difficult to make out. Peripheral (side) vision typically remains intact, so dry AMD does not cause total blindness. But losing central vision significantly affects the ability to read, drive, and perform detail-oriented tasks.
Who Is at Risk
Age is the strongest risk factor. Most people diagnosed are over 60. Smoking is the most significant controllable risk factor, as it directly increases oxidative damage to the retina and alters levels of key immune proteins involved in the disease.
Genetics play a major role. A variant in the complement factor H gene, part of the immune system’s inflammatory pathway, is strongly linked to AMD. People who carry two copies of the risk variant are about 7.4 times more likely to develop the disease. Family history of AMD is one of the clearest warning signs, and the interplay between genetic susceptibility and environmental exposures like smoking determines much of an individual’s overall risk.
How It’s Diagnosed
A standard dilated eye exam can reveal drusen and pigment changes in the macula, which is often enough for an initial diagnosis. For a more detailed picture, eye specialists use optical coherence tomography (OCT), a painless imaging scan that creates cross-sectional images of the retina in high resolution. OCT can detect subtle early changes like focal thickening of the RPE, tiny hyperreflective spots within the retina, and thinning of the photoreceptor layer, all of which may appear before vision symptoms do.
OCT is also the primary tool for monitoring progression over time. It can identify early signs that geographic atrophy is developing and can catch conversion to wet AMD by detecting fluid beneath the retina. Another imaging method, fundus autofluorescence, highlights areas of RPE loss by mapping the natural fluorescence of lipofuscin, making patches of geographic atrophy clearly visible.
Slowing Progression With Supplements
The most studied intervention for dry AMD is the AREDS2 formula, based on a large clinical trial conducted by the National Eye Institute. The supplement combination is recommended for people with intermediate AMD or advanced AMD in one eye and includes 500 mg vitamin C, 400 IU vitamin E, 10 mg lutein, 2 mg zeaxanthin, 80 mg zinc, and 2 mg copper (added to prevent zinc-related copper deficiency). The original AREDS formula contained beta-carotene instead of lutein and zeaxanthin, but that version is not recommended for current or former smokers because beta-carotene increases lung cancer risk in that group.
AREDS2 supplements do not cure AMD or restore lost vision. They reduce the risk of progressing from intermediate to advanced disease. For people with only early-stage AMD, the evidence of benefit is less clear, and the supplements are generally not recommended at that stage.
Diet and Lifestyle Factors
A Mediterranean-style diet, rich in fruits, vegetables, fish, olive oil, and low in red meat, has a strong association with slower AMD progression. One study found that people with high adherence to this dietary pattern were 2.2 times more likely to experience slowed disease progression compared to those with low adherence. Pooled data from two large European studies found a 41% lower risk of developing advanced AMD among people who closely followed a Mediterranean diet, with a particularly strong protective effect against geographic atrophy specifically.
The benefits likely come from several overlapping mechanisms. The diet is naturally high in lutein and zeaxanthin (found in leafy greens), which are the same pigments used in the AREDS2 supplement and which concentrate in the macula to filter damaging blue light. It’s also rich in omega-3 fatty acids from fish, which have anti-inflammatory effects and may protect RPE cells from oxidative stress. The overall pattern is low-glycemic, antioxidant-rich, and anti-inflammatory. People who followed the Mediterranean diet and took an antioxidant supplement showed the greatest benefit compared to those who did one or neither.
Treatments for Advanced Dry AMD
For decades, there was no approved treatment for geographic atrophy. That changed in 2023 with two new medications, both delivered by injection into the eye. The first, approved in early 2023, works by blocking a protein called complement factor 3, a central hub in the immune system’s inflammatory cascade that drives RPE destruction. The second, approved in August 2023, targets complement factor 5, a downstream step in the same pathway.
Both treatments slow the expansion of geographic atrophy rather than reversing it. They require ongoing injections, typically monthly or every other month. They do not restore vision that has already been lost, but they can help preserve remaining vision by slowing the rate at which healthy retinal tissue is destroyed. These are the first therapies to directly target the underlying immune-driven process of advanced dry AMD, and their approval represents a significant shift in how the condition is managed.