ROLE OF NUTRITION IN MAINTAINING NORMAL EYESIGHT-A REVIEW
Keywords:Vitamin A, DHA, Glaucoma, retinopathy
The eye is particularly susceptible to oxidative stress as a result of its high oxygen consumption, high concentration of polyunsaturated fatty acids and cumulative exposure to high-energy visible light. This combination of factors leads to the generation of reactive oxygen species that can trigger oxidative damage to ocular tissues. There is evidence that the human consumer should avoid excessive supplementation with carotenoids. Poly-unsaturated fatty acids are linked to eye disease (as well as multiple other chronic diseases) in both positive and negative ways. Dietary poly-unsaturated fatty acids fall into two major groups, i.e., omega-6 (mainly linoleic acid and arachidonic acid) and omega-3 fatty acids, mainly alpha-linolenic acid, eicosapentaenoicacid (EPA) and docosahexaenoic acid (DHA). Vitamin A deficiency is rare in the United States, but it is common among the poor in developing countries. It's estimated that approximately 250,000 to 500,000 malnourished children worldwide become blind each year due to vitamin A deficiency that could have been prevented with a proper diet. A lack of vitamin A causes the cornea to become very dry, leading to clouding of the front of the eye, corneal ulcers and vision loss. Vitamin A deficiency also causes damage to the retina, which also contributes to blindness.
Keywords: Vitamin A, DHA, Glaucoma, retinopathy