Carrot: To ease kids' suspicion of vegetables, parents often feed them the adage that carrots will spare them from corrective vision care. But is there any truth to the commonly held belief that carrots are good for your eyes?
Well, yes and no. Carrots won't improve your visual acuity if you have less than perfect vision. For example, a diet of carrots won't give a blind person 20/20 vision. But the vitamins found in the vegetable can help promote overall eye health. Carrots contain beta-carotene, a substance that the body converts to vitamin A, an important nutrient for eye health.
For centuries, carrots have been connected with health benefits. In the Middle Ages, carrots were believed to cure anything from sexually transmitted diseases to snakebites. Carrots became associated with vision, particularly night vision, during World War II. The British Royal Air Force published a story that said skilled fighter pilot John "Cats' Eyes" Cunningham could thank a steady diet of carrots for his night vision flying prowess. In response to the story, many British people began to grow and eat more carrots. They wanted to improve their vision so that they could see better during the compulsory blackouts that were common during World War II. Although Cats' Eyes' carrot eating made for a great story, it was, in fact, propaganda put out to conceal the fact that the Royal Air Force's was actually using radar to locate Luftwaffe bombers during the night.
Broccoli: To protect your eyesight, try broccoli. An antioxidant found in broccoli may be a powerful force in preventing blindness.
Researchers at Johns Hopkins University School of Medicine have discovered that sulforaphane, the naturally occurring antioxidant in broccoli and broccoli sprouts, protects the eye from damage caused by the sun's ultraviolet light.
Cells in the eye's retina are extremely sensitive to damage caused by oxidants, especially those generated by light. While several processes within the eye help cut that damage, the eye gradually loses that capability as we age.
This is believed to be the primary cause of age-related macular degeneration -- the leading cause of blindness, writes researcher Xiangqun Gao, a molecular scientist with the Johns Hopkins University School of Medicine. His report appears in the current issue of theProceedings of the National Academy of Science of the USA.
To combat this damage, a simple long-term strategy is important, Gao notes. That's where sulforaphane comes in.
Previous studies from this group of researchers have shown that sulforaphane prevents tumor growth and kills stomach bacteria that lead to ulcers and stomach cancer. In one study, they showed that feeding broccoli sprouts to rats prevented high blood pressure, heart disease, and stroke.
In their latest laboratory experiment, the Johns Hopkins researchers exposed human retina cells, which protect against oxidative stress and free radicals, to various doses of sulforaphane. Then they exposed cells to ultraviolet light -- similar to sunlight -- to produce oxidative damage.
Sulforaphane protected eye cells from damage, reports Gao. In fact, the more sulforaphane exposure the cells got, the more protection they received.
"Much evidence points to the central role of oxidative damage in chronic degenerative diseases of the eye," writes Gao. A diet high in broccoli and broccoli sprouts is a safe, long-term approach to preventing age-related macular degeneration and blindness, he says.
Apricots: are rich in the carotenoids and xanthophylls, nutrients that researchers believe may help protect eyesight from aging-related damage To give an example of how this works, one of these nutrients (lutein) appears to be able to protect the retina—the part of the eye that picks up the visual image from the environment—from damage caused by blue light.
Additionally, researchers have linked regular intake of fruit with less risk of vision loss with aging. This benefit is found in people who eat three or more servings of fruit each day.
Three servings of fruit may sound like a lot to eat each day, but by simply snacking on an apricot, tossing a banana into your morning smoothie, and topping off a cup of yogurt or green salad with one-half cup of berries, you've reached this goal.
Spinach: and other dark, leafy greens are rich in two antioxidants stored in the macula—lutein and zeaxanthin. The macula is a part of the retina that acts as a natural sunblock, shielding the eye from damaging light. Lutein and zeaxanthin absorb blue light, which is especially harmful to the retina. These nutrients can also help the eye detect contrast better, so eating foods rich in these antioxidants not only improves vision, but they help maintain your vision long-term. Since lutein and zeaxanthin are fat soluble, eating your greens with olive oil will help ensure that you absorb more of them.
Red Pepper: Age-related macular degeneration (AMD) and cataracts are leading causes of vision loss, but foods rich in lutein, zeaxanthin, and vitamin C, like bell peppers, can keep eyes sharp. A cup of sliced red, yellow and orange peppers contains nearly twice your daily vitamin C, plus 116 micrograms (mcg) of lutein, and 562 mcg of zeaxanthin.
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