Dry Age-Related Macular Degeneration –Prevention with A Plant-Based Diet

Abstract

Age-related macular degeneration (ARMD) is the leading cause of blindness in the developed world. No effective therapy exists for the dry form of ARMD, which makes up about 90% of cases. Major modifiable risk factors have been identified such as cigarette smoking, obesity, nutritional factors, and alcoholism. The risk of dry ARMD is increased by several modifiable etiologic factors in particular – lack of blue light filtration, oxidative stress, and inflammation. Two components of plant foods, lutein and zeaxanthin, screen out blue light, resulting in greater macular pigment optical density (MPOD), and act as antioxidants in the macular. A plant-based diet also reduces inflammation and lowers hsCRP. These factors combine to give vegetarians a lower risk of dry ARMD. Epidemiological studies have shown that consuming meat raises the risk of dry ARMD while consuming plant foods lowers the risk. Studies have shown significant correlations between high lutein concentration in ocular tissues or in serum and reduced risk of ARMD. Vegetarians have been found to have a greater MPOD. A broad range of antioxidants from plant foods, sulforaphane, can reduce oxidative damage, and may decrease the risk of dry ARMD. Elevated levels of hsCRP, a marker of inflammation, predict greater future risk of ARMD. On a vegan diet hsCRP was reduced 32%, even more than on the American Heart Association diet.