“Finish your carrots, they’re good for eyes” you may have heard your mother say a time or two. Carrots contain Vitamin A which plays an important role in optimum vision health. But there are quite a few nutrients that may be even more important then Vitamin A in supporting a clear and healthy visual system.
Here we highlight 7 vitamins, minerals, and herbal supplements and the research that supports their role in protecting and improving your eyesight.
Dr. Benjamin C. Lane, O.D., from the Nutritional Optometry Institute in New Jersey, says, “Americans are getting less chromium and much more of its major antagonist, vanadium (a trace element) because of recent dietary trends to large marine fish and poultry.”
In numerous tissue testing and diet assessment studies that Dr. Lane has performed over the past twenty years he has found that “low levels of chromium are a major risk factor for increased intraocular pressure.” Chromium plays a large role in muscle contraction which is why this occurs when deficiencies are present.
And yet another negative effect of near-point activities like computer use, Dr. Lane reports that “the set of muscles we use more than ever before, are those that help focus our eyes.” He has conducted several studies that have shown that straining to focus over a period of time, does in fact increase intraocular pressure. But with proper amounts of chromium in your diet, focusing may be easier and less stressful to your eyes.
The body does not make chromium naturally, so it must be obtained through your diet. The best sources of chromium are beef, liver, eggs, chicken, oysters, wheat germ, green peppers, apples, bananas, and spinach.
Vitamin C's importance as an antioxidant cannot be overstated. The Web site All About Vision even calls this vitamin the "Vision Superhero"!
Vitamin C has been linked to the prevention of cataracts - one study has shown that taking 300 to 600 mg supplemental vitamin C reduced cataract risk by 70 percent - the delay of macular degeneration, and eye pressure reduction in glaucoma patients.
It's an interesting fact that, while most animals produce their own vitamin C, we humans do not have that ability. In addition, we can't store this vitamin in our bodies for very long, so it needs to be constantly replenished to obtain its benefits.
Most of us think of orange juice as the quintessential source of vitamin C, but many vegetables are actually even richer sources: chili peppers, sweet peppers, kale, parsley, collard, and turnip greens are full of vitamin C, as are broccoli, Brussels sprouts, watercress, cauliflower, cabbage, and strawberries.
Lutein and Zeaxanthin
Lutein, found in our retinas, is essential for healthy vision. Lutein and a related dietary carotenoid, zeaxanthin, accumulate within the retina and imbue a yellow pigment that helps protect the eye.
It lowers the risk of cataracts and macular degeneration (low lutein intake is implicated as a risk factor in age-related macular degeneration), and may also help to prevent or slow down atherosclerosis.
Lutein is found in the red, orange, and yellow pigments of fruits and vegetables; for example, tomatoes, carrots, and squash. Green leafy vegetables such as spinach also contain high amounts of lutein.
Clinical research has determined that lutein along with zeaxanthin are two naturally occurring carotenoids present in the macular segment of the retina.
The concentration of these two is so high in the macula (the retinal region responsible for fine visual activities), that the carotenoids are visible as a dark yellow spot, called the macular pigment, in normal, healthy retinas. They act like sunglass filters to protect the eye.
Research performed at Harvard Medical School has established that dietary zeaxanthin plays an essential role in protecting the retina of the eye from the damaging effects of light.
Epidemiologic studies have shown that people with higher lutein/zeaxanthin levels have reduced risk for advanced stages of macular degeneration.
Blue-eyed individuals need more lutein and zeaxanthin because they have less of these protective pigments in their retinas. Again, dark, leafy greens are the dietary winner here, along with corn, nectarines, oranges, papaya and squash.
Our eyes actually contain the greatest concentration of zinc in our body. Just like you need a bulb to convert electricity into light, your body needs zinc to convert beta-carotene into vitamin A.
Oysters contain more zinc per serving than any other food, but red meat and poultry provide the majority of zinc in the American diet.
Selenium is a trace mineral that our bodies need to boost immunity and fight off infections. It can also help prevent cataracts and macular degeneration by acting as an antioxidant that neutralizes free radicals that can damage the eye's lens and macula; studies have identified low selenium levels in cataract sufferers.
Selenium also helps your body to absorb vitamin E. Fish, shellfish, red meat, grains, eggs, chicken, liver, and garlic are all good sources of selenium, as well as brewer's yeast and wheat germ.
Glutathione is an amino acid that protects the tissues surrounding the lens of the eyes. According to Web MD, "It also has potentially widespread health benefits because it can be found in all types of cells, including the cells of the immune system, whose job is to fight disease."
Numerous studies link glutathione with the prevention of cataracts, glaucoma, retinal disease, and diabetic blindness. Foods that increase glutathione levels include sulfur-rich foods such as garlic, eggs, asparagus, and onions, and glutathione-rich foods such as watermelon, asparagus, and grapefruits.
The ginkgo is the oldest living tree species, growing on earth for 150-200 million years. No surprise, then, that it's one of the most well-researched herbs in the world. Studies have confirmed that ginkgo, a powerful antioxidant increases blood flow to the retina and can slow retinal deterioration which results in an increase of visual acuity.
Retinal damage has a number of potential causes, including diabetes and macular degeneration. Studies suggest that gingko may help preserve vision in those with macular degeneration.