Healthy sight requires adequate vitamins, as well as ample oxygen and continuous blood supply. Vitamin deficient diets are major contributors to eye diseases, such as macular degeneration. According to the National Eye Institute, about 9 million Americans over the age of 40 suffer from macular degeneration. Certain vitamins can reduce the prevalence and slow the progression of macular degeneration.
Macular Degeneration
Macular degeneration usually affects older adults and is the gradual loss of vision in the center of the visual field, called the macula, because of retinal damage. Retinal damage is often a result of lack of blood, which carries oxygen and nutrients. The small arteries that supply the retina are susceptible to blockage, damage and leaking. High blood pressure, atherosclerosis, toxins, diabetes, and lack of anti-oxidant vitamins contribute to blood vessel damage. According to "Professional Guide to Diseases," macular degeneration can make it nearly impossible to read or recognize faces, although over 95 percent of peripheral vision remains to allow other activities of daily life. Consequently, macular degeneration cannot cause total blindness.
Vitamin A
Vitamin A and its precursors, such as beta-carotene, are strong antioxidants that protect blood vessels from the ravages of free radicals and oxidation. Free radicals promote inflammatory reactions, tissue deterioration and general aging. The small blood vessels that feed the eye are especially susceptible to free radical damage. Beta-carotene is also a powerful antioxidant that protects blood vessels, although lutein and zeaxanthin are the only carotenoids within the retina and lens of the eye. According to the Linus Pauling Institute, diets rich in lutein and zeaxanthin may slow the progression of age-related macular degeneration and cataracts. Further, a study published in a 2004 edition of "Optometry" found that visual acuity in patients with macular degeneration significantly improved with lutein supplementation.
Vitamin C
The National Eye Institute notes that macular degeneration occurs more often and progresses quicker in the elderly, especially low income individuals, so it is believed that an accumulation of free radical damage and dietary deficiencies play important roles in the disease. Vitamin C, due to its antioxidant properties, protects the blood vessels that carry oxygen and nutrients to the retina. Vitamin C is also required to produce collagen and connective tissue, which strengthen and repair blood vessels. Further, vitamin C reduces blood cholesterol levels, which reduces the risk of clogged vessels.
Vitamin E
Vitamin E is another antioxidant that destroys free radicals, but it also promotes efficient blood flow by reducing platelet cells from clumping together. A Spanish study published in a 1999 edition of "Mechanisms of Aging and Development" noted that patients who had the lowest serum levels of vitamin E had the most severe forms of macular degeneration. Further, the "British Medical Journal" published a 2007 analysis of prospective cohort studies and found that people with high dietary consumption of vitamin E have a 20 percent lower risk of age-related macular degeneration compared to those with low dietary intakes.
References
- National Eye Institute: Macular Degeneration
- "Professional Guide to Diseases: Ninth Edition"; Springhouse Publishing; 2009
- Linus Pauling Institute: Oregon State University: Vitamin A
- "Optometry"; Double-masked, placebo-controlled, randomized trial of lutein and antioxidant supplementation in the intervention of atrophic age-related macular degeneration: the Veterans LAST study (Lutein Antioxidant Supplementation Trial); S. Richer et al.; April 2004
- "Mechanisms of Aging and Development"; Serum Vitamin E Levels Negatively Correlate with Severity of Age-related Macular Degeneration; J. Belda et al.; March 1999
- "British Medical Journal"; Dietary antioxidants and primary prevention of age related macular degeneration: systematic review and meta-analysis; E. Chong et al; October, 2007
