Nutrition for Healthy Eyes

Research suggests that antioxidants and other important nutrients may reduce your risk of cataracts and macular degeneration.

Specific antioxidants can have additional benefits as well; for example, vitamin A protects against blindness, and vitamin C may play a role in preventing or alleviating glaucoma.

Omega-3 essential fatty acids appear to help the eye in a variety of ways, from alleviating symptoms of dry eye syndrome to guarding against macular damage.
Eye Benefits of Vitamins and Micronutrients

The following vitamins, minerals and other nutrients have been shown to be essential for good vision and may protect your eyes from sight-robbing conditions and diseases.

Incorporating the following foods in your diet will help you get the Recommended Dietary Allowance (RDA) of these important eye nutrients. Established by the Institute of Medicine (National Academy of Sciences), the RDA is the average daily dietary intake level of a nutrient sufficient to meet the requirements of nearly all healthy individuals in a specific life stage and gender group.

While the RDA is a useful reference, some eye care practitioners recommend higher daily intakes of certain nutrients for people at risk for eye problems. In the following list, mg = milligram; mcg = microgram (1/1000 of a mg) and IU = International Unit.

Beta-carotene

* Eye benefits of beta-carotene: May protect against night blindness and dry eyes.

* Food sources: Carrots, sweet potatoes, spinach, kale, butternut squash.

* RDA: None (Most supplements contain 5,000 to 25,000 IU).

Bioflavonoids (Flavonoids)

* Eye benefits of bioflavonoids: May protect against cataracts and macular degeneration.

* Food sources: tea, red wine, citrus fruits, bilberries, blueberries, cherries, legumes, soy products.

* RDA: None.

Lutein and Zeaxanthin

* Eye benefits of lutein and zeaxanthin: May prevent cataracts and macular degeneration.

* Food sources: Spinach, kale, turnip greens, collard greens, squash.

* RDA: None.

Omega-3 Fatty Acids

* Eye benefits of omega-3 fatty acids: May help prevent macular degeneration (AMD) and dry eyes.

* Food sources: Cold-water fish such as salmon, mackerel and herring; flaxseed oil and fish oil; ground flaxseeds and walnuts.

* RDA: None. (For cardiovascular benefits, the American Heart Association recommends approximately 1,000 mg daily.)

Selenium

* Eye benefits of selenium: When combined with carotenoids and vitamins C and E, may reduce risk of advanced AMD.

* Food sources: Seafood (shrimp, crab, salmon, halibut); Brazil nuts; enriched noodles; brown rice.

* RDA: 55 mcg for teens and adults (60 mcg for women during pregnancy and 70 mcg when breast-feeding).

Vitamin A

* Eye benefits of vitamin A: May protect against night blindness and dry eyes.

* Food sources: Beef or chicken liver, cod liver oil, eggs, butter, milk.

* RDA: 3,000 IU for men; 2,333 IU for women (2,567 IU during pregnancy and 4,333 IU when breast-feeding).

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The key to eye health: Sunglasses

UV Damage and Your Eyes
Much more than a fashion accessory, sunglasses are an essential tool in protecting your vision. Studies show that exposure to the sun's ultraviolet (UV) rays can harm the lens and cornea of the eye, leading to problems -- like cataracts and macular degeneration -- that can impair vision. And the thin skin around the eye and the eyelid itself are especially vulnerable to skin cancer and to sun-induced signs of aging. Dr. Gail Royal, an ophthalmologist in Myrtle Beach, S.C., admits that she sometimes appeals to her patients' vanity when she discusses the importance of proper sunglass use. "I'll point out that sunglasses will protect not just against basal cell and squamous cell carcinomas and melanoma," she says, "but also against the formation of wrinkles like crow's-feet and the unsightly thickening of the skin that can sometimes be caused by UV exposure."

Here's how to choose a pair of sunglasses that will safeguard your eyes.

Look for Complete UV Protection
Whether you spend $200 for a pair of designer sunglasses or buy one off the drugstore rack for $20, both can do an equally good job of blocking harmful ultraviolet rays. Look for a label or sticker that says the lenses block 99 or 100 percent of UVA and UVB rays. Sunglasses with full protection might also say something like, "Lenses meet ANSI Z80-3 blocking requirements," or "UV 400 protection." Sunglass boutiques sometimes remove these labels or stickers for a more attractive display. Chances are the shades provide full UV protection; just be sure to ask.

Color Counts If You're Behind the Wheel
It may seem logical that a darker lens would do a better job of blocking the sun's harmful rays than a lighter lens, but that turns out not to be the case. The coating that blocks UV radiation is clear, so shades of any hue are equally effective at filtering those rays. Yellow or rose-tinted lenses can, however, make it difficult to distinguish changes in traffic lights. Gray, green and brown lenses minimize color distortion.

Focus on Fit
To block the light that hits your eye from the sides, choose wraparound frames. Your next best bet? Sunglasses with large lenses and wide temples, like the iconic oversized frames Audrey Hepburn wore in Breakfast at Tiffany's. Whatever the style, frames should fit snugly on your nose and ears without pinching or rubbing, but not so close that your eyelashes hit the lens.

Choose Polarized Lenses If You Water Ski, Surf or Fish
Polarized lenses reduce glare by filtering out the reflected light that bounces off water. Polarization, however, has nothing to do with UV light absorption, so check the label to make sure they provide maximum UV protection. Keep in mind that, when you're wearing polarized lenses, it may be difficult to read your cell phone, GPS device or a liquid-crystal display on a dashboard or an ATM machine.

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Color blindness

What is colour blindness?
Sometimes a person may not have as many of the different types of cone cells, or they may be missing altogether. This means that some people cannot see some colours.
Some people may be unable to see the colours green and red – this is the most common type of colour blindness. They might see red as orange and green as white.
Some people may have cones missing which cause them to be unable to see blue and yellow.
How your eyes see colour
Light from the sun or from a light bulb bounces off everything that your eyes see and goes through the pupil (the black hole in the centre of the front of your eye).
The light reaches the retina, which is like a movie screen at the back of your eye.
How do you get colour blindness?
Defective colour vision, as it is called by doctors and scientists, is something which is passed on in the genes. That means that a person gets it from his parents, and they got it from their parents.
Most of the people with colour blindness are male – about 1 boy in 10 will be colour blind, while only about 1 girl in 200 will be colour blind.

'Radical' surgery uses patient's tooth to restore her sight

Doctors in Miami announced Wednesday that they had performed a vision-restoring surgery that used the 60-year-old patient's tooth.

The surgery, the first in the USA, was performed Labor Day weekend at the Bascom Palmer Eye Institute at the University of Miami Miller School of Medicine. Afterward, patient Sharron Thornton was able to see for the first time in nine years. "Sharron was able to see 20/60 this morning. She was seeing only shadows a couple of weeks ago," says ophthalmologist and surgeon Victor Perez.

Sharron Kay Thornton talks with her lead surgeon Victor Perez who restored sight to her left eye at the University of Miami Bascom Palmer Eye Institute in Miami, Florida. The procedure implanted one of her teeth in her eye, as a base to hold a prosthetic lens.

Thornton was blinded in 2000 by a reaction to a drug she was taking, which damaged her cornea. Perez likened Thornton's cornea to a dirty car windshield. He says her eye surface was too dry for a corneal implant, a standard treatment.

Thornton's eye tooth and part of her jaw bone were removed, then sculpted to create a hole in the tooth through which a optical cylinder lens fit. The tooth acts as a base to hold the lens.

The prosthesis was then placed in a pouch just under the skin of Thornton's cheek, where it would remain for several months to allow for the growth of a living capsule around it.

To surgically implant the tooth-lens prosthesis, a hole was made in the cornea and the capsule embedded over the top of the cornea. The mucous membrane was then pulled back over the eye like a blanket and a hole made for the lens.

"It's a pretty radical operation and can be disfiguring," says James Chodosh, a faculty member at the Massachusetts Eye and Ear Infirmary. But he says the results are worth it to patients.

Thornton says being able to see again is "like Christmas."

source: http://www.usatoday.com/news/health/2009-09-16-eye-tooth_N.htm