In addition, vitamin A is an essential part of vision. The first signs of vitamin A deficiency, which can also be an issue for the elderly in developed countries, include night blindness, and persistent deficiency can result in total vision loss. Supplying an adequate amount of vitamin A or its precursor beta-carotene is vital for good vision (30).
In the eye, vitamin C is highly concentrated in the lens, where it works as an antioxidant. Numerous scientific studies have linked increased intakes of vitamin C alone (31) or in combination with other antioxidants such as vitamin E, beta-carotene and zinc (32) with long-term protective effects against the development of cataract and AMD in an older population.
Also the vitamins B9 (folate / folic acid), B6 and B12 have been shown to reduce the risk of AMD (33), probably by reducing the blood concentration of homocysteine, which is thought to be a risk factor for diseases of blood vessels, like AMD.
Furthermore, the omega-3 fatty acids docosahexaenoic acid (DHA), an important component of retinal pigment cells, and eicosapentaenoic acid (EPA) are vital for an optimal function of the eye. A high intake of DHA and EPA has been associated with a 40% reduction in the risk of AMD (34).