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http://en.wikipedia.org/wiki/Macular_degeneration
Nutritional supplements
Some evidence supports a reduction in the risk of age-related macular degeneration with increasing intake of two carotenoids, lutein and zeaxanthin[28] and a large clinical trial is running from 2008 to 2014 to see if they can influence the progression of this disease.[29]
Consuming omega-3 fatty acids (DHA & EPA) has been correlated with a reduced progression of early ARMD, and in conjunction with low glycemic index foods, with reduced progression of advanced ARMD.[30]
An earlier, Cochrane Database Review of publications to 2007 found that the use of vitamin and mineral supplements, alone or in combination, by the general population had no effect on age-related macular degeneration,[31] a finding echoed by another review.[32] A 2006 Cochrane Review of the effects of vitamins and minerals on the slowing of ARMD found that positive results mainly came from a single large trial in the United States (the Age-Related Eye Disease Study, with funding from the eye care product company Bausch & Lomb who also manufactured the supplements used in the study[33]), and questioned the generalization of the data to any other populations with different nutritional status. The review also questioned the possible harm of such supplements, given the increased risk of lung cancer in smokers with high intakes of beta-Carotene, and the increased risk of heart failure in at-risk populations who consume high levels of vitamin E supplements.[34]