Specific antioxidants may reduce your risk of eye diseases like cataract and age related macular degeneration. In fact, the essential eye specific nutrients can protect against blindness and dry eye as well, and are essential for eye health.
These micronutrients and antioxidants include vitamin A, C and E, omega-3 essential fatty acids and carotenoids, flavonoids, lutein and zeaxanthin. Selenium and zinc are minerals that help maintain eye health.
Importance of Vitamins and micronutrients for eye health
Vitamins, minerals and other nutrients may protect your eyes from several sight threatening diseases. They are essential for good vision and eye health. As is true for your general health and well being, a balanced diet must include plenty of fruits and vegetables. In addition, certain micronutrients are found in oily fish, milk products, nuts and seeds.
The Institute of Medicine (National Academy of Sciences) has specified the Recommended Dietary Allowance (RDA) or Daily Reference Intake (DRI) of the essential eye specific nutrients. The RDA is the recommended average daily dietary intake level of a nutrient for healthy living. Since the requirement for each age group is different, this index varies according to age and gender.
Benefits, sources and RDA of eye specific nutrients
Beta-carotene
- Beta carotene is the fat soluble orange pigment that gives fruits and vegetables their orange color. It may retard the progression of AMD. In addition, other essential micronutrients that help in AMD include zinc, vitamins C and E. Beta carotene is found in carrots, sweet potatoes, butternut squash, red bell peppers, broccoli, peas, cantaloupe and apricots. Other sources include green leafy vegetables like spinach, kale and lettuce. Increased intake of beta carotene may increase the risk of lung cancer in smokers. Consequently, you must be cautious when using beta carotene supplements.
- The RDA for beta carotene is around 10800 μg
Bioflavonoids
- Flavonoids, or bioflavonoids, are found in almost all fruits and vegetables. In fact, together with carotenoids, they are the reason for the colors in colors in fruits and vegetables. Bioflavonoids are known to protect against cataracts and age related macular degeneration. Onions, tea, strawberries, kale, grapes, Brussels sprouts, citrus fruit, parsley, and legumes are good sources of bioflavonoids.
- There is no RDA for bioflavonoids.
Lutein and Zeaxanthin
- Like the above mentioned eye specific nutrients, lutein and zeaxanthin also help prevent cataracts and macular degeneration. Good sources of these micronutrients are spinach, kale, turnip greens, collard greens, squash, saffron and broccoli.
- There is no RDA for lutein and zeaxanthin.
Omega-3 Fatty Acids
- Omega 3 and Omega 6 Fatty Acids are essential for eye health. These essential fatty acids, EFAs, improve the nerve conduction in retina. This consequently reduces the risk of vision loss due to macular degeneration and glaucoma. Omega 3 Essential Fatty Acids are found in oily fish like salmon, mackerel, herring and halibut. Vegetarian sources include walnuts, flax seed, soyabean and dark leafy vegetables. Linoleic acid, vegetable safflower, sunflower oil, and grape seeds are also rich sources of EFAs.
- There is no RDA for eyes, but the American Heart Association recommends approximately 1,000 mg daily for heart health.
Vitamin A
- Vitamin A helps prevent night blindness, dry eyes (xerosis), and macular degeneration. Rich sources of this vitamin include beef or chicken liver; eggs, butter, milk.
- The RDA for men is 3000 IU. It is 2333 IU for women. The RDA is 2,567 IU during pregnancy and 4333 IU during breast-feeding.
Vitamin C
- Vitamin C is a potent antioxidant and fights free radical injury. It consequently prevents ultra violet radiation induced damage within the eye, and also fights signs of ageing. It helps promote healthy blood vessels and reduces the risk of cataracts and macular degeneration. Vitamin C is found in bell peppers, kale, strawberries, broccoli, oranges, cantaloupe and other citrus fruits.
- The RDA is 90 mg for men. For women, the RDA is 70 mg (85 mg during pregnancy and 120 mg when breast-feeding).
Vitamin E
- Vitamin E regulates enzyme activity, and help in neurological functions. Along with carotenoids and vitamin C, it reduces the risk of AMD. Vitamin E is found in nuts and seeds like almonds, sunflower seeds, hazelnuts.
- The RDA for Vitamin E is 15 mg.
Zinc
- Zinc reduces the risk of night blindness along with Vitamin A. Additionally, zinc and selenium may help reduce the risk of advanced AMD. Food sources of zinc include oysters, beef, crab, and turkey. Seafood like shrimp, crab, salmon and halibut are rich sources of selenium. In addition, Brazil nuts and brown rice are also rich in the micronutrient.
- The RDA of zinc for men is 11 mg. For women, this allowance is 8 mg, increasing to 11 mg and 12 mg respectively, during pregnancy and lactation. Men and women both require around 55mcg of selenium. On the other hand, the RDA increases to 60 mcg and 70 mcg respectively, during pregnancy and lactation.
Diet for healthy eyes
- Incorporate a wide variety of foods in your diet. They are rich sources of eye specific nutrients. Therefore, make sure you eat whole grains and cereals, and lots of fruits and vegetables.
- Include healthy fats in your diet. Oils rich in the essential fatty acids help prevent dry eyes, AMD and cataract. In addition, they help in absorption of oil soluble vitamins and micronutrients.
- Choose lots of colorful fruits and vegetables. These are rich sources of vitamins and minerals, which protect your eye health.
- Make sure you get adequate protein. Remember to limit your consumption of red meats and dairy products. These are rich in saturated fats which can increase the risk of AMD. Good sources of protein are lean meats, oily fish, nuts, legumes and eggs.
Eye specific nutrient supplements
There are several supplements in the market, with eye specific formulations. You do not need supplements usually. However, most of us do not consume the recommended five portions of fruit and vegetables a day. We may, therefore, need a nutritional supplement.
Your doctor may also prescribe nutritional supplements for you. He will do so in case you have been diagnosed with AMD, cataract or dry eye. There is empirical evidence that these may slow progression of the disease.
These supplements are by and large safe to use. However, you must consult your doctor if you are pregnant or breastfeeding. Eye specific nutrients are fat soluble. Consequently, they are stored in the body. Hence, you must be careful to not overdo the supplements as they can lead to toxicity also. You must therefore discuss the optimum dose and duration of these nutritional supplements with your eye doctor.
