Macular degeneration is one of the eye diseases with the strongest genetic component—more than 50% of its heritability is attributable to identified variants. The main genes involved are CFH (complement factor H), ARMS2, and HTRA1, whose risk variants are present in 40 to 60% of patients with advanced AMD. Having an affected first-degree relative increases the risk by a factor of 3 to 4. This predisposition does not determine an unchangeable fate—environmental factors (smoking, diet, UV exposure) account for the remaining half and are modifiable. Family-based screening via fundus examination is recommended starting at age 50 for at-risk individuals.
DHA (docosahexaenoic acid) makes up 60% of the fatty acids in the membranes of macular photoreceptors. Its presence is essential for membrane fluidity and for the transduction of light signals by opsins. Cohort studies show that consuming fatty fish twice a week (≥ 500 mg/day of DHA) is associated with a 40% reduction in the risk of advanced AMD. DHA in the form of marine phospholipids (krill oil) has 50–60% higher bioavailability than conventional triglycerides.
Rich in delphinidin-3-rutinoside and cyanidin-3-glucoside, the anthocyanins in blackcurrants (Ribes nigrum) improve choroidal microcirculation by reducing platelet aggregation and the adhesion of leukocytes to the vascular endothelium. Their in vitro anti-VEGF activity inhibits choroidal neovascularization—a mechanism relevant to the wet form of the disease. Japanese studies (Nakaishi et al., 2000) show an improvement in visual acuity and night vision with 50 mg/day of standardized extract. Their combination with lutein and zeaxanthin in eye supplements has a synergistic effect.
Drusen—deposits of oxidized proteins and lipids beneath the retina—are an early hallmark of dry AMD. Curcumin from turmeric inhibits NF-kB in retinal pigment epithelium cells and reduces the expression of complement genes (CFH, C3) involved in their formation. EGCG in green tea inhibits MMPs, which degrade Bruch’s membrane—a structural layer whose deterioration initiates drusen formation—and its retinal bioavailability following oral administration has been documented through in vivo imaging.
Low serum vitamin D levels (< 20 ng/mL) are associated with an increased risk of AMD and faster progression of the dry form. Vitamin D3 receptors (VDR) are expressed in retinal pigment epithelium cells—their activation regulates genes involved in local inflammation and the complement response. A meta-analysis (Yi et al., 2021) confirms a significant inverse association between vitamin D levels and the risk of AMD. Preventive intake: 2,000 to 4,000 IU/day—levels should be measured before starting any long-term supplementation.
AMD and cardiovascular diseases share the same mechanisms—atherosclerosis of the choroidal vessels, low-grade inflammation, and chronic oxidative stress. According to meta-analyses, hypertension increases the risk of neovascular AMD by 30 to 50% by weakening the walls of subretinal neovessels. Controlling blood pressure, LDL cholesterol, and blood sugar levels is an integral part of preventive care. The AMD page details the AREDS2 formula and complementary active ingredients for each stage of the disease.
