If you are following all the basic dietary recommendations discussed in this booklet and using the cooking methods which protect the essential nutrients in food, you may be getting all the vitamins, minerals, phytochemicals, complex carbohydrates, fats and proteins your eyes and body require. However, very few of us can consistently eat all the fresh fruits and vegetables, seafood, nuts, seeds, and healthy wild meats and fats on a daily or weekly basis to meet our needs.
Our modern food industry with its long storage and transportation of our food resources, combined with the mineral depleted soils that our foods are grown in, contribute to making much of our food nutrient deficient even before it is cooked and eaten. The many chemical pollutants and other environmental stresses we have to deal with can also quickly deplete the body of its stored nutrient defences.
It would appear to be “common sense and common science” to supplement our diet with appropriate antioxidant vitamin and mineral supplements. It is good insurance against the various nutritional deficiencies and oxidative stresses that we experience in our daily lives.
Optimal vision depends on healthy eyes and a healthy brain, since they are intimately connected. The retina and brain contain a large amount of delicate omega-3 fats and we need to do as much as we can to protect their health and function from oxidative damage.
There are many eye related supplements on the market and many claims about their superiority over other brands. The Ocular Nutrition Society supports the use of natural ingredients as much as possible in any ocular vitamins.
There are several major nutrients, which in diet and supplement form have been shown in various studies to reduce the risk of macular degeneration, diabetic retinopathy and cataracts. These nutrients include the omega-3 fats that replenish the retina and the antioxidant vitamins and minerals that protect them. These are:
· EPA and DHA, known as the long-chain omega-3 essential fatty acids
· Vitamin A
· Vitamin C
· Vitamin D
· Vitamin E
· Lutein and zeaxanthin
EPA and DHA are the fatty acid building blocks of the eye’s retina and the brain. Lutein and zeaxanthin are the only two plant carotenoids that are deposited in the macula (the most sensitive part of the retina) and eye’s crystalline lens to protect them from damage by ultraviolet light. Vitamins A, C, D, E and the mineral zinc are the essential antioxidant substances that work together to protect the ocular tissues from oxidation.
Our Top Five Ocular Supplement Recommendations
1. A daily supplement of two teaspoons of natural source cod liver oil is our primary recommendation for adults, children over 12 years and nursing mothers. It is the best natural source of EPA, DHA, and vitamins A and D. Two teaspoons provides 1,000 to 2,000 mg of EPA and DHA, 10,000 International Units (IU) of vitamin A and 2,000 IU of vitamin D. Although vitamin A can be toxic in long-term use in amounts over 30,000 IU, this is more commonly associated with synthetic vitamin A in the absence of vitamin D.
Natural vitamin A is called retinol and is found only in foods of animal origin. Synthetic vitamin A is manufactured as vitamin A acetate or palmitate. Synthetic vitamin D is manufactured as vitamin D2 (ergocalciferol) and natural vitamin D occurs as vitamin D3 (cholecalciferol.)
Beta-carotene is often used as a source of vitamin A in supplements. Beta-carotene is a carotenoids derived from plants which is converted in the liver into retinol, the active form of vitamin A. Unless the supplement is listed as “natural beta-carotene” it is synthetic and should be avoided, especially by those who smoke heavily or drink alcohol regularly. Beta-carotene supplements can reduce blood levels of lutein. It's best if you keep the beta-carotene limited to your carrot intake and not add more via supplements.
2. A daily supplement of 10 mg of lutein with zeaxanthin has been shown to reduce the risk of macular degeneration and cataracts. These pigments are deposited into the central area of the retina to protect it from high energy light degeneration. Lutein cannot be absorbed without the presence of dietary fat.
3. A daily supplement of 500 mg of a vitamin C complex preferably taken in two daily doses of 250 mg will help protect the eye and body from oxidative damage. Vitamin C is the body’s most important water-soluble antioxidant acting primarily in cellular fluid to prevent oxidation and inflammation. Most supplements of vitamin C are the synthetic form called ascorbic acid. However, when combined with the bioflavonoids that are found with natural vitamin C in fruits and vegetables, it forms a close-to-natural “complex” of ingredients that make vitamin C more bioactive. Look for vitamin C supplements that have added bioflavonoids such as rosehips, hesperidin, rutin and citrus bioflavonoids.
4. A daily supplement of 200 IU of vitamin E complex with the natural vitamin E form d-alpha tocopherol is the body’s most important fat-soluble antioxidant. It acts to protect our cell membranes and other fat molecules from damage. The synthetic version of vitamin E, called dl-alpha tocopherol, is less potent. Look for supplements with a complex of “mixed tocopherols,”, or tocotrienols meaning they also contain the beta, delta, and gamma forms of vitamin E.
5. A daily supplement of 15 to 20 mg of zinc can help prevent the deficiencies that play a significant role in diabetic retinopathy and macular degeneration. Zinc protects the structure and function of retinal cell membranes by helping to reduce oxidative damage. It is found in high concentrations in the retina and brain. Look for supplements that contain zinc monomethionine. Other forms such as zinc citrate and zinc gluconate are not as bioavailable.
These five recommendations are the essentials. There are other important nutrients that can be incorporated into this list such as selenium, manganese, acetyl-l-carnitine, Co-enzyme Q10 and lipoic acid. These nutrients function to enhance the effectiveness of the body’s antioxidant defences and help to regulate blood sugar. They play a significant role in maintaining healthy eyes and vision. They can be found together in a variety of quality multi-vitamin and multi-mineral ocular supplements.
It is always best to take supplements with meals since the body’s absorption of the nutrients is generally enhanced by the digestive process when we eat. Some of the best and most natural sourced supplements can be found in health food stores and vitamin specialty shops. Be well informed and always read labels.
Always talk to you doctor before starting a program of vitamin and mineral supplements.