Nutrients to Maintain Vision Throughout Life 15 Feb 2013
Aging is only better than the alternative – not getting old. So many parts of your body change. One of the changes is visual acuity. At least that must be the reason because there aren’t any clear indicators my arms are shortening!
Age-related macular degeneration (AMD) is a leading cause of irreversible visual loss. Although AMD has many contributing factors, nutrition influences visual performance. The retina of the eye concentrates two dietary carotenoids, lutein and zeaxanthin, and the long-chain omega-3 fatty acid, docosahexaenoic acid (DHA). DHA is an important constituent of photoreceptor membranes and has many beneficial effects (anti-inflammatory, anti-angiogenisis, and anti-apoptotic) in the retina. Choosing carotenoid-rich foods or supplements can increase macular pigment density which has been shown to reduce glare discomfort , shorten recovery time to bright light (e.g. oncoming headlights at night), and enhance visual acuity (distance and contrast).
Merle and associates assessed the relationship between plasma omega-3 fatty acids and late age-related macular degeneration (AMD) in 963 French residents over 73y of age. They report that higher plasma omega-3 fatty acids are associated with a ~40% reduction in AMD. Significant correlations were observed for DHA concentrations as well. Previously, Souied and colleagues reported the effects of a randomized controlled trial (RCT) where 840 mg/d DHA and 270 mg/d eicosapentaenoic acid (EPA) was compared with an olive oil placebo in 263 patients with AMD over 3 y. Despite great variability in DHA and EPA concentrations in serum and red blood cell membranes in both treatment groups, they found significantly less choroidal neovascularization in individuals with a consistently high omega-3 fatty acid index throughout the study.
With the publication of AREDS2 results anticipated this year, the effects of antioxidant nutrients and omega-3 fatty acids on eye health should be much clearer. In the meantime, attend IFT Wellness 13 session in Chicago, IL entitled “Seeing is Believing: Nutrients for Visual Performance” for a science update. -mm-
Merle BMJ, Delyfer M-N, Korobelnik J-F, Rougier M-B, Peuchant E, Letenneur L, Dartigues J-F, Colin J, Barberger-Gateau P, Delcourt C. High concentrations of plasma n3 fatty acids are associated with decreased risk of late age-related macular degeneration. 2013 J Nutr doi:10.3945/jn.112.171033
Hammond BR, Fletcher LM, Elliott JG. Glare disability, photostress recovery, and chromatic contrast: Relation to macular pigment and serum lutein and zeaxanthin. 2012 Invest Opthalmol Vis Sci DOI: 10.1167/iovs.12-10411
Souied EH, Delcourt C, Querques G, Bassols A, Merle B, Zourdani A, Smith T, Benlian P. Oral docosahexaenoic acid in the prevention of exudative age-related macular degeneration. 2013 Opthalmol DOI: 10.1016/j.ophtha.2013.01.005