Healing Kitchen

Lutein & Zeaxanthin
As researchers continue to uncover the health-protective benefits of fruits and vegetables, adages like "eating carrots is good for your eyes" don't seem so silly. Scientists are finding that pumpkins are good for the lungs and tomatoes may protect the prostate. And while carrots may indeed be good for the eyes, studies suggest that many other fruits and vegetables may be even better at protecting vision.

Choosing a diet full of colorful fruits and veggies--like yellow corn, orange peppers, and leafy collard greens--will help guard against macular degeneration, the leading cause of blindness in older people. The macula, the yellow-pigmented part of the retina at the back of the eye, is responsible for detailed vision, but as we age it tends to break down. The condition occurs when the retina becomes excessively thinned and scarred with age.

People with macular degeneration tend to have low blood levels of antioxidants. And antioxidants are important because they protect us against excess free radicals--the cell-damaging compounds believed to hasten age-related decline, including retinal degeneration. Free radicals are also thought to contribute to cataracts, another major cause of vision loss, as well as cancer and heart disease.

Sight-saving antioxidants include vitamins C and E; anthocyanosides (found in blueberries and bilberries, a European relative of the blueberry); and orange-yellow plant pigments called carotenoids (the best known is beta-carotene). But two other carotenoids, lutein and zeaxanthin, seem to have special significance for vision. That's because they are vital components of the macula, where they help filter out harmful ultraviolet rays.

A small study conducted over the Internet suggests these carotenoids may also improve vision in people with retinitis pigmentosa, a genetic disorder marked by retinal degeneration (Optometry, 3/00). Further study is needed to confirm this benefit.

And the winner is... A study from the University of Texas Medical Branch in Galveston and the University of Heidelberg Medical School in Germany separated the lutein and zeaxanthin content of different fruits and vegetables. Kiwifruits were especially high in lutein, followed by red grapes, zucchini, pumpkin, spinach, and yellow squash. Orange peppers topped the zeaxanthin list, which included orange juice, honeydew, mangoes, and peaches. Egg yolks and corn were also high in both substances.

Check your multi. Recently, lutein has been added to multivitamins such as Centrum. But according to Dr. John Hurst of the University of Texas, the 250 mcg (0.25 mg) added to one tablet is a low amount. "I dont think this amount will achieve very much." Other supplements contain varying amounts of lutein (3 to 20 mg) and zeaxanthin. If youre taking a supplement with one of these substances, be sure to eat a little fat with your pill. "Otherwise theyll just pass through," says Dr. Hurst.

Suggested dose: Although no daily value has been established, getting at least 5 mg of lutein and 400 mcg of zeaxanthin daily, along with a blend of other carotenoids, seems a reasonable goal. You might try a "mixed carotenoid" formula. Take two mixed carotenoid pills each morning with food. Each pill should supply 25,000 IU vitamin A activity.

Author: the WholeHealthMD Advisor
Date Published: 09/17/2000
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