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Wednesday, April 14, 2010

Veggies, fruits, fish and supplements will help keep your vision sharp as you age

Veggies, fruits, fish and supplements will help keep your vision sharp as you age
By Evelyn Theiss, The Plain Dealer

http://www.cleveland.com/healthfit/index.ssf/2010/04/veggies_fruits_fish_and_supple.html


CLEVELAND, Ohio - Maybe a trim waistline isn't enough motivation for you to eat more leafy greens and fish.

What about the idea of keeping your eyesight well into old age?

Good nutrition for eye health goes beyond carrots and their beta carotene, doctors now say, and the addition of some key nutrients can help avoid two leading causes of vision loss and blindness -- age-related macular degeneration and cataracts -- and aid conditions such as dry eyes.

Researchers who study the connection between diet and eye health say certain supplements might be helpful even for those who do eat their vegetables, especially once you hit your 40s. That's when many age-related eye problems begin to crop up.

Rocky River optometrist Mark Davis spends his spare time studying the impact of nutrition on vision and eye health, as an active member of the Ocular Nutrition Society, an international society devoted to eye health.

"I am so tickled that more and more professionals are embracing the aspect of good nutrition for eye health," says Davis, who co-owns Europtical in Rocky River with his wife, Simona. "The field is recognizing that people want to know about this -- they're interested in supplements, too -- and now we're doing more research to find what is beneficial and what isn't."

The nutrients that Davis currently encourages his patients to take include lutein (it helps with night vision), zeaxanthin (it protects the eyes from ultraviolet damage and prevents free-radical damage to the retina and lens), omega-3 oils (the DHA in them prevents retinal damage), zinc (good for preventing macular degeneration) and vitamin A (helps our night vision, but excessive doses can be toxic.)

Lutein, especially, is crucial when it comes to eye health as we age -- it is present in the macula of the retina and helps us discern fine details. We are born with a certain amount, but since the body doesn't produce it, the amount of lutein in your eyes depletes with age -- so the only way to get it is by ingesting it.

Some foods -- the same ones that are bad for the rest of your body -- are bad for you eyes as well. Hydrogenated oils, for example, are linked with arterial plaque, inflammation, diabetes and other chronic illnesses. Too much saturated fat -- say, more than one main-dish-sized serving a week of beef, pork or lamb -- has been shown to increase the risk of macular degeneration. There also seems to be a link between being overweight and eye disease (independent of the eye damage, retinopathy, related to diabetes) including an increased risk for cataracts and glaucoma.

Study showed effectsof zinc, antioxidants
Davis' interest in the connection between nutrition and the eyes was forged when he was doing his residency at the Veterans Affairs hospital in Cleveland in 1992. That hospital was one of the research-gathering sites for what would become the National Institutes of Health's study on age-related macular degeneration, or AMD.

It's referred to by doctors as AREDS, an acronym for Age-Related Eye Disease Study. Results showed that high levels of antioxidants and zinc significantly reduced the risk of advanced AMD and its associated vision loss. (A second AREDS is under way.)

"That truly spearheaded my, and a lot of other people's, interest in the connection between vitamins and minerals and vision," says Davis.

The optometrist recently returned from a professional meeting of the Ocular Nutrition Society in Atlanta in late February, where much of the focus in the lectures was on how antioxidants found in fruits, vegetables and supplements aid eye health, as do omega-3 oils.

"This wasn't the Reader's Digest version we heard," says Davis. "Everything was all about the clinical studies, what they're showing, what they're looking at next."

Age-related macular degeneration is the leading cause of blindness in people older than 50 -- and AREDS revealed that people with macular degeneration were able to achieve a 25 percent reduction in its progression when they upped their intake of key antioxidants combined with a zinc supplement (tinyurl.com/aredstudy shows more details).

Hundreds more studies have been done since then on eye health and nutrition, and much more research will take place in the next five years, says Davis, especially into lutein, zeaxanthin and omega-3s. "We have enough research to show these are beneficial, but we need more clinical data to back that up."

Most people don't eat enough fruits, veggies
Steven Meadows, an eye surgeon with offices in Fairview Park and Lakewood, also is intrigued by the effects of a healthy diet.

"I tell patients that if you eat at least three servings each of fruits and vegetables a day, you'll probably get everything you need," he says. "But today, most people don't do that, so it's worth taking vitamins and supplements."

Meadows says that he is at increased risk of macular degeneration because he is farsighted, has blue eyes and a family history of the disease. The main risk factor, though, is age. So he has become meticulous about eating more fruits and vegetables.

"I've seen the research that says people who eat spinach two times a week develop macular degeneration at a lower rate," he says. And after researchers determined that, they isolated lutein in spinach as making that contribution.

Soon after, lutein became an ingredient incorporated into supplements aimed at healthy vision.

Meadows says one of the most common problems many of his patients have -- and a condition more common with age -- is dry eyes. It's especially a problem for women who are postmenopausal, and for those who wear contact lenses. Working in front of a computer all day can aggravate it, too.

For people with dry eyes, he recommends omega-3 fatty acids, either taken in the form of eating fatty fish like salmon three or four times a week, or adding ground flaxseed to foods, or taking fish-oil or flaxseed-oil supplements.

"Your body can't manufacture the omega-3, so you have to take it in," he explains. He said he's seen a dramatic difference in tear quality with people who get a good dose of the oil, and those healthy tears often help people achieve less-blurry vision.

"I don't eat enough fish, so I take it myself," Meadows says.

Eye doctors say the demand for their services is expected to dramatically increase over the next few years, due to a major portion of the population aging into eye problems and to the diabetes epidemic.

The Ocular Nutrition Society predicts, "Disease prevention, including lifestyle modification, attention to dietary intake and micronutrient supplementation must become more of a focus of primary vision care."

What can you do? Eat more veggies, more often. Then add fruit.

How much should you take?

You've heard it before: Ideally, you need at least nine servings total of fruits and vegetables a day for your eyes and your general health.

Yet the Centers for Disease Control and Prevention has said less than 15 percent of the population consumes even five servings of fruits and vegetables a day.

People who eat fish more than four times a week have a lower risk of macular degeneration than those who consume it less than three times a month. Omega-3 fatty acids are known to improve blood circulation to the eye.

So try to improve your nutrition -- taking baby steps if you need to -- and consider taking supplements. We've added the amounts (in milligrams and international units) of most of the nutrients that research has shown to be helpful for your eyes, in case you decide to boost your totals using supplements.

The main nutrients shown to help you keep your eyes healthy as you age are those with the antioxidants lutein and zeaxanthin; essential fatty acids (omega-3s in particular); vitamins A, B, C and E; and zinc.

In the Age-Related Eye Disease Study, the National Eye Institute (of the National Institutes of Health) found that the combination of daily supplements to bring down the risk or progression of age-related macular degeneration is: 500 mg of vitamin C, 400 IU of vitamin E, 15 mg of beta carotene, 80 mg of zinc oxide and 2 mg of copper, also known as cupric acid. For the second ARED study now under way, the level of zinc has been cut back to 25 mg.

As always, it's best to talk to your doctor for advice before starting a new regimen.

Contact Evelyn Theiss: etheiss@plaind.com or 216-999-4542.
By Evelyn Theiss, The Plain Dealer

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