Micronutrients are essential for eye function, and researchers have probed the influence of many vitamins on eyesight. As of 2010, no significant research has identified minerals that may affect eyesight. Vitamin A is often considered necessary for eye function, but researchers have yet to conclusively recommend a vitamin or mineral supplement that will benefit the eye. Consult your doctor before beginning any supplementation routine.
Vitamin A
Vitamin A is a fat-soluble vitamin found in spinach, beets, liver, milk, eggs and orange or red fruit and vegetables. Beta-carotene, also found in some of these foods, is a precursor to vitamin A. The recommended dose of vitamin A is 900 micrograms for men, and 700 micrograms for women. In 2001, research published in the journal "Archives of Ophthalmology" by the Age-Related Eye Disease Study Research Group concluded that a vitamin A supplement had no effect on vision loss in people aged 55 to 80. It has been speculated that vitamin A improves vision and prevents vision loss in those with a vitamin A deficiency. Despite reports that beta-carotene prevents cataracts, there is no evidence as of 2010 that supports this contention.
B Vitamins: Thiamin and Riboflavin
Among the many vitamins in the B complex, riboflavin and thiamin have been the most frequently mentioned for their influence on vision. Since they are water-soluble, there is little risk of toxicity if taken as a supplement. Thiamin is found in meats, legumes, seeds and whole grains. It is thought that decreasing thiamin intake can lead to vision loss, but, as of 2010, there is no evidence that supplementation with thiamin can improve vision. Riboflavin --- found in dairy, meat and eggs --- may reduce overall risk for cataracts, but more research is needed to confirm this recommendation.
Vitamin C
Vitamin C is a water-soluble vitamin and provides a significant amount of antioxidant protection for the eye. For this reason, it is possible that vitamin C reduces the risk of cataracts. A study published in 1992 in the "British Medical Journal" found a possible connection between women who took a vitamin C supplement over a 10-year period and reduced risk of cataracts. The tolerable upper intake level for vitamin C in adults is 2,000 milligrams per day.
Vitamin E
Vitamin E is a fat-soluble vitamin found in plant oils and some nuts and fruits. The tolerable upper intake level for vitamin E is about 1,000 milligrams per day. Vitamin E supplementation may, due to its antioxidant properties, prevent cataracts caused by age-related degeneration, but more research is needed as of 2010 to confirm this correlation.
References
- "The Health Professional's Guide to Popular Dietary Supplements"; Allison Sarubin Fragakis and Cynthia Thomson; 2007
- "Archives of Ophthalmology"; A randomized placebo controlled clinical trial of high-dose supplementation with vitamin C and E and beta-carotene for age-related cataract and vision loss; Age-Related Eye Disease Study Research Group; 2001
- "American Academy of Ophthalmology"; The Blue Mountain Eye Study; R. Cummings et al.; 2000
- "British Medical Journal"; Nutrient intake and cataract extraction in women: a prospective study; S. Hankinson et al.; 1992
