Nutrition and Eye Health
Increasingly, researchers are finding a link between good nutrition and maintaining healthy eyes. Researchers now believe that age-related eye diseases that are caused by the body's exposure to the normal oxidation process may be slowed by vitamins and minerals found in fruits and vegetables or taken in supplement form. Because current studies are looking at different vitamins or combinations of vitamins, it is not yet possible to say definitively which vitamins should be taken by whom or in what quantities.
Nonetheless, it is more and more apparent that a diet rich in fruits and vegetables high in antioxidants may help prevent age-related eye problems such as cataracts and macular degeneration, or at least slow their progress.
Macular Degeneration
The causes of this disease are not completely understood, but it is now known that light sensitive cells of the macula may degenerate over time. Risk factors for the disease may include smoking, exposure to sunlight, hypertension, and a high cholesterol level. Diets high in antioxidants (such as vitamin C) and carotenoids (such as carrots, kale and spinach) may slow some of the degenerative processes in the retina that can lead to age-related macular degeneration. A number of studies now link macular health with a high lutein content of the macula. A heterochromic flicker photometer (Macuscope) is now commercially available that is capable of measuring the amount and density of macular lutein which is a significant factor in preventing macular disease. It has been shown that taking 20mgm of lutein daily will bring the amount of pigment to normal levels in 120 days. Taking a higher dose does not significantly affect the level of lutein.
Cataracts
The clouding of the lens, typical of cataract, may be related to exposure to ultraviolet light and the accompanying oxidation process. As in macular degeneration, this process appears to be slowed by a diet rich in antioxidants, specifically vitamin C.
The key vitamins for both conditions appear to be vitamin C (ascorbic acid), folic acid, selenium and zinc. These are found in leafy green vegetables, carrots, citrus fruits and melons.
Spinach, kale and collard greens, which provide lutein and zeaxanthin (carotenoids) seem to be particularly beneficial for the macula.
Caution should be exercised regarding three antioxidants: vitamin A, beta-carotene and vitamin E. Vitamin A in excess of 5000 units has been linked with osteoporosis. Beta-carotene has been associated with lung cancer in smokers. Vitamin E in excess of 400 units has been linked with excessive blood thinning. Patients who are on coumadin or aspirin should be particularly cautious about their vitamin E dosage.
Points to Keep in Mind
While vitamins can be obtained by taking supplements, it is best to get as many of these nutrients as possible through your diet. A diet high in fruits and vegetables and low in saturated fat, trans fats and sugar will help not only your eyes but also your overall health.
Although increasing your intake of antioxidants will probably not restore vision that is already lost, it may slow the progress of the disease.
If you are considering either changing your diet to include more foods rich in antioxidants and/or taking vitamin supplements, consult your physician. Some people have other health considerations that could be affected by these dietary changes.
Smoking is thought to be a significant risk factor in eye health. Studies show that quitting smoking can have significant benefits at any age.
Nutrition and health are lifelong concerns. Don't wait until you develop an eye problem or other health concern to make changes in your diet.
If you already have vision loss and have been told it cannot be helped by surgery, medicine, or standard glasses, you may want to consider seeing a low vision specialist. These specialists can prescribe optical devices such as magnifiers, telescopes, or adaptive devices that can help you use your remaining sight more effectively and refer you on for other vision rehabilitation services that will help you maintain your independence.