The World Health Organization defines nutrition as the intake of food according to the body’s dietary needs. Good nutrition, described as having an adequate and well-balanced diet is vital in order to boost one’s immunity, enhance physical and mental development, and decrease incidence of illness or disease.
There are several vitamins and minerals needed in order to maintain good eyesight. Since most of them are antioxidants, they prevent damage to the eyes and all of its vital structures. The following vitamins and minerals are recommended in one’s diet in order to promote eye health.
Vitamin A is a known antioxidant needed in order to maintain healthy corneas and conjunctivae. Deficiency in this vitamin is the number one cause of blindness all over the world. In this condition, known as keratomalacia, the cornea does not develop and degenerates. Because vitamin A is fat soluble and cannot be readily excreted by the body when taken in large doses, it is advised that one gets most of it from the diet. Foods that are rich in this vitamin include sweet potatoes, carrots, squash and other brightly colored vegetables, green leafy vegetables, fish and liver. Pro-vitamin A or beta-carotene is also an important precursor to vitamin A, and is found mostly in dairy products, green-, orange- and yellow-colored vegetables.
Oranges and any type of citrus fruit are known to be rich in vitamin C. Just like vitamin A, this is also a strong anti-oxidant that helps fight free radicals that can damage the eyes. In the Journal of Investigative Ophthalmology, they found out that vitamin C is secreted into the aqueous humour of the eye where it is more concentrated than in other body fluid, suggesting its particular importance to the lens.
Vitamin E is a fat-soluble antioxidant that stops the production of free radicals in the body. Studies showed that this vitamin, when combined with vitamin C had a synergistic effect in preventing cataract occurrence. A deficiency in this particular vitamin also showed poor development of the retina, a light-sensitive layer of the eye that sends images received from the lens of the eye, and immediately sent to the brain. When a person experiences changes in color perception, flashes of lights, floater or distortion in vision, a retinal examination with the help of your ophthalmologist is advised.
Spinach, kale and other green, leafy vegetables are very rich in vitamin E. Studies showed that there was decreased incidence of cataract in those who ate spinach daily, while other sources of vitamin E include vegetable oils and fish particularly salmon, tuna and other oily fish.
Other Essential Vitamins
Other vitamins which showed beneficial effects on the eyes include the different B vitamins (B1, B2, B3, B6 and B12), which are vital in maintaining healthy optic nerve function.
Zinc is an important mineral needed in cellular metabolism and immune function of any major organ in the body, particularly the eyes. It was found that zinc concentration in the retina and choroid parts of the eye was normally one of the highest levels of the body, making its presence crucial in the metabolism of the retina and lens and prevention of cataract occurrence. Aside from this, zinc also plays an important role in the overall health of the eye, because of its ability to prevent free radicals from affecting it. When deficient in the diet, one can experience night blindness.
Because of its antioxidant properties, selenium has been associated with decrease in occurrence of cataracts and macular degeneration. Very rich in selenium are seafood, meats, cereals, dairy products and fruits and vegetables.
According to Nutrition in Clinical Care, carotenoids are thought to provide health benefits in decreasing the risk of disease, particularly certain cancers and eye disease. In the carotenoid family are the beta-carotenes, lycopene, lutein, and zeaxanthin. Beta-carotenes and lycopenes are known antioxidants, while lutein and zeaxanthin are known to absorb damaging blue light that enters the eyes.
Essential Fatty Acids
Omega-3 fatty acids are essential for the normal development of the eye and brain in an infant and is provided in breast milk. These fatty acids are also important in retinal function and has been shown to reduce incidence of cardiovascular disease, even benefitting the arteries supplying the eye.
Good nutrition is something that benefits not only our eyes, but the rest of our body as well. Through current research and studies, we have discovered that nutritional supplements do play a role in the prevention of eye disease. Middle-aged and elderly individuals seem to benefit more from supplementation since it may be deficient in the diet and absorption is not as effective as we grow older.