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Lutein and Macular Degeneration Improvement Supplementation with lutein, either alone or combined with antioxidants and other nutrients, improves vision in people with age-related macular degeneration (ARMD), reports a study in Optometry (2004;74:1–15). Earlier research had shown that lutein is important for the retina, the light-sensitive membrane lining the inner eye. This is the first controlled trial to show that supplementation benefits people with ARMD, in both early and advanced stages. ARMD is a chronic, degenerative disease, in which the part of the retina that controls central vision (the macula) gradually breaks down. ARMD is the most common cause of vision loss in elderly people in Western countries, causing nearly half of all cases of impaired vision or blindness in the United States. Ninety percent of these cases are “dry,” or atrophic, characterized by progressive loss of pigment in the retina. The other 10% of cases are “wet” ARMD, which is caused by the excessive growth of new blood vessels within the retina. Laser treatment may halt or slow the progression of wet ARMD but has not been generally found to improve the more common dry form. Fortunately, a growing body of research suggests that various nutritional supplements might help slow or stop progression of the disease. Lutein is a carotenoid (a molecule similar to beta-carotene) found in large amounts in spinach and, to a lesser extent, in other dark green, leafy vegetables, corn, and egg yolk. In the body, lutein becomes concentrated in the macula of the retina, where it filters out the eye-damaging blue-light component of the sun’s rays. Studies have suggested that the presence of high concentrations of lutein in the macula may reduce the risk of developing macular degeneration. Other research has demonstrated that supplementing with lutein increases the concentration of lutein in the macula. In the new study, 90 people with dry ARMD were randomly assigned to receive daily treatment with one of the following for 12 months: (1) 10 mg of lutein (an amount present in approximately 2 ounces of spinach, (2) the same dose of lutein plus a combination of various nutrients that may enhance retinal health (for example, antioxidants, zinc, bilberry, taurine, quercetin, N-acetylcysteine, and others), or (3) placebo. Treatment with lutein, either with or without the additional nutrients, resulted in an improved capacity to filter out toxic blue light. Moreover, in both groups receiving lutein, there was an improvement in visual acuity (equivalent to an improvement of up to one line on a standard eye chart) and in contrast sensitivity (another measure of visual function). By some measures, combination therapy was somewhat more effective than lutein alone, and by other measures lutein by itself was more effective. The beneficial effect of lutein was seen both in people with early ARMD and in those with more advanced disease—an important observation, because it has been generally assumed that advanced ARMD is relatively resistant to treatment. The results of this study demonstrate that supplementing with lutein, or eating spinach or other foods high in lutein content, may preserve or even enhance visual function in people with ARMD. With the publication of this report, it seems more likely than ever that Popeye will be remembered as a true visionary. Alan R. Gaby, MD, an expert in nutritional therapies, testified to the White House Commission on CAM upon request in December 2001. Dr. Gaby served as a member of the Ad-Hoc Advisory Panel of the National Institutes of Health Office of Alternative Medicine. He is the author of Preventing and Reversing Osteoporosis (Prima, 1994), and co-author of The Natural Pharmacy, 2nd Edition (Healthnotes, Prima, 1999), the A–Z Guide to Drug-Herb-Vitamin Interactions (Healthnotes, Prima, 1999), Clinical Essentials Volume 1 and 2 (Healthnotes, 2000), and The Patient’s Book of Natural Healing (Prima, 1999). A former professor at Bastyr University of Natural Health Sciences, in Kenmore, WA, where he served as the Endowed Professor of Nutrition, Dr. Gaby is the Chief Medical Editor for Healthnotes, Inc. Copyright © 2004 Healthnotes, Inc. All rights reserved. Republication or redistribution of the Healthnotes® content is expressly prohibited without the prior written consent of Healthnotes, Inc. Healthnotes Newswire is for educational or informational purposes only, and is not intended to diagnose or provide treatment for any condition. If you have any concerns about your own health, you should always consult with a healthcare professional. Healthnotes, Inc. shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Healthnotes and the Healthnotes logo are registered trademarks of Healthnotes, Inc.
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