The lens of the eye focuses an image of the world on a portion of the retina called the
, the area of finest visual perception. Gradual deterioration of the macula is called macular degeneration. After
In the most common form of macular degeneration (dry macular degeneration), a substance known as lipofuscin accumulates in the lining of the retina. A much less common form of macular degeneration involves the abnormal growth of blood vessels (wet macular degeneration). This can be treated very successfully, if attended to soon enough, but may lead to irreversible blindness if left untreated. For this reason, medical consultation in all cases of macular degeneration (or any other type of vision loss) is essential.
Principal Proposed Natural Treatments
Note : The treatments described in this section are intended as support to standard ophthalmalogical care, not as a substitute for it. In addition, all studies refer primarily to the more common type of macular degeneration, dry macular degeneration.
Zinc and Antioxidants
A single solid study suggests that zinc, or a mixture of zinc and antioxidants can prevent or slow the progression of early macular degeneration. However it is not clear whether the antioxidant portion of this mixture added any additional benefit.
trial evaluated the effects of zinc with or without antioxidants on macular degeneration in 3,640 individuals in the early stage of the disease.
: Zinc at doses of 80 mg and higher daily can be harmful.
One of the problems is that high-dose zinc supplementation impairs copper absorption. That's why extra copper was provided in the study described above. However, there may be other risks as well. Physician supervision is advised. For other dosage and safety issues, see the full
Smaller studies of zinc for macular degeneration have found mixed results.
Note that it’s not clear how much the antioxidants in the mixture contributed to the benefits. In fact, there is no convincing evidence that antioxidants alone are effective for preventing or delaying the onset of macular degeneration. A 4-year, double-blind, placebo-controlled trial of 1,193 people with macular degeneration failed to find vitamin E alone helpful for preventing or treating macular degeneration.
Lutein and Other Carotenoids
As noted above, in one very large study, beta-carotene failed to prove effective for preventing macular degeneration. However, the less well-known carotenoids lutein and zeaxanthin might be more promising.
These hopes received support from a double-blind, placebo-controlled trial.
Other Proposed Natural Treatments
Like carotenoids, flavonoids are found in many plants and may offer a variety of beneficial effects. Weak but interesting evidence suggests that bilberry
In observational studies, people who happen to consume a diet rich in
1. Age-Related Eye Disease Study Research Group. A randomized, placebo-controlled, clinical trial of high-dose supplementation with vitamins C and E, beta carotene, and zinc for age-related macular degeneration and vision loss: AREDS Report no.8. Arch Ophthalmol. 2001;119:1417-1436.
10. Mares-Perlman JA, Fisher AI, Klein R, et al. Lutein and zeaxanthin in the diet and serum and their relation to age-related maculopathy in the Third National Health and Nutrition Examination Survey. Am J Epidemiol . 2001;153:424-432.
12. Lebuisson DA, Leroy L, Rigal G. Treatment of senile macular degeneration with Ginkgo biloba extract. A preliminary double-blind, drug versus placebo study [translated from French]. Presse Med . 1986;15:1556-1558.
15. Age-Related Eye Disease Study Research Group. A randomized, placebo-controlled clinical trial of high-dose supplementation with vitamins C and E and beta carotene for age-related cataract and vision loss: AREDS report no. 9. Arch Ophthalmol. 2001;119:1439-1452.
18. Richer S, Stiles W, Statkute L, et al. Double-masked, placebo-controlled, randomized trial of lutein and antioxidant supplementation in the intervention of atrophic age-related macular degeneration: the Veterans LAST study (Lutein Antioxidant Supplementation Trial). Optometry . 2004;75:216-230.
20. Feher J, Kovacs B, Kovacs I, et al. Improvement of Visual Functions and Fundus Alterations in Early Age-Related Macular Degeneration Treated with a Combination of Acetyl-L-Carnitine, n-3 Fatty Acids, and Coenzyme Q10. Ophthalmologica . 2005;219:154-166.
21. Bartlett HE, Eperjesi F. Effect of lutein and antioxidant dietary supplementation on contrast sensitivity in age-related macular disease: a randomized controlled trial. Eur J Clin Nutr . 2007 Jan 31. [Epub ahead of print]
25. Chong EW, Kreis AJ, Wong TY, et al. Dietary omega-3 fatty acid and fish intake in the primary prevention of age-related macular degeneration: a systematic review and meta-analysis. Arch Ophthalmol. 2008;126:826-833.
Last reviewed April 2009 by EBSCO CAM Review Board
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
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