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Seeing Clearly: Protecting Your Vision with Nutrients |
Protecting the eyes as we age is an important part of avoiding several medical conditions that can severely impair vision if not prevented. Age related macular degeneration is the most common cause of vision loss in the elderly. Based on years of scientific study we know that certain nurtrients are key in preventing the damage that ultimately causes the progression of these diseases.
Due to the high level of constant activity in the eye, it is one of the highest producers of free radicals in the body second to the brain. It has been hypothesized that as we age the enzymes that breakdown and neutralize the free radicals in the eye become less active and the eye structures are more vulnerable to damage.
Certain nutrients are key for neutralizing the negative effects of free radicals and it is these exact nutrients that have shown promising results in clinical studies to prevent and even sometimes reverse ocular damage associated with age related vision disorders.
The Age Related Eye Disease Study was a clinical trial sponsored by the National Eye Institute, one of the National Institutes of Health in the United States. It examined the effects of high dose antioxidant therapy for macular degeneration and cataracts. The study evaluated 3,600 people over the course of about 4 years and determined that anti-oxidants such as Vitamin C, zinc, beta carotene and Vitamin E reduced certain risks of progression and development of macular degeneration by as much as 25%.
Other antioxidant nutrients in the form of lutein and zeaxanthin (zee-uh-zan'-thin) also have shown promising effects when it comes to protecting the eyes from age related macular degeneration. These are the only two carotenoids that the light sensitive retina of the eye will absorb and concentrate. Lutein and zeaxanthin exist in such high levels in certain parts of the retina that they can be seen as a yellowish area. More recent research points towards zeaxanthin as having the more active role of antioxidant protection in the eye due to the fact that it concentrates in the areas of the eye most prone to oxidative damage. Further, zeaxanthin’s chemical structure is superior at quenching free radicals when compared to that of lutein. A recent Harvard study demonstrated the importance of these two antioxidants in protecting the eye from light damage by measuring the amount of damage induced in the retina of Chinese quail given a diet deficient in lutein and zeaxanthin. Animals that were supplemented with lutein and zeaxanthin sustained far less injury to their retina when exposed to higher intensity light. Chinese quail were chosen because their retinas concentrate similar concentrations of lutein and zeaxanthin and are most similar to human retinas when compared with other animals.
Eating a diet rich in natural antioxidants and high in lutein and zeaxanthin is a great way to improve eye health.
Here are some foods which are known to be high in zeaxanthin, listed in order from highest to least (>100mcg/100g serving), according to the Lutein and Zeaxanthin Scientific Review:
Pepper, orange, raw...1608
Corn, sweet, yellow, canned...528
Persimmons, Japanese, raw...488
Corn, frozen, cooked...375
Spinach, raw...331
Turnip greens, cooked...267
Collard greens, cooked...266
Lettuce. cos or romaine, raw...187
Spinach, cooked...179
Kale, cooked...173
Tangerine, mandarin...142
Supplementation is also an excellent way to improve levels of these important nutrients and protect your eyes. Many eye formulas exist and contain anti-oxidants such as Vitamin C, E, zinc and beta-carotene. In addition they often contain lutein, zeaxanthin bilberry and other natural antioxidants.
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