A letter published online on June 24, 2007 in the journal Nature Medicine reported the finding of researchers at Children's Hospital Boston, Brigham and Womenโ€s Hospital, Massachusetts General Hospital, the University of Goteborg in Sweden, and the National Institutes of Health, that omega-3 polyunsaturated fatty acids have a protective effect in mice against the development and progression of deterioration of the retina of the eye, known as retinopathy. Retinopathy in mice shares characteristics with retinopathy of prematurity (ROP) in human infants, as well as with diabetic retinopathy and age-related macular degeneration (AMD) in adults.
Lois Smith, MD, PhD, and Kip Connor, PhD, of Childrenโ€s Hospital Bostonโ€s Department of Ophthalmology, and associates gave mice diets high in the omega-3 fatty acids EPA and DHA, or in the omega-6 fatty acid arachidonic acid, and examined the animals' retinas. They found that greater dietary omega-3 fatty acid content reduced the area of vessel loss which leads to the regrowth of abnormal vessels that characterizes retinopathy. โ€It is remarkable that with only a two percent change in dietary omega-3 intake, we observed an approximate 40-50 percent decrease in retinopathy severity,โ€ Dr Connor stated.
The omega-3s create bioactive mediators which protect against abnormal blood vessel growth by suppressing tumor necrosis factor alpha, an inflammatory protein found in microglia associated with retinal blood vessels. โ€If omega-3 fatty acids, or these anti-inflammatory mediators, are as effective in humans and they are in mice, simple supplementation could be a cost-effective intervention benefiting millions of people,โ€ Dr Smith observed. โ€The cost of blindness is enormous.โ€
"The purpose of our study was to discover and describe the scientific basis for any possible protective role of omega-3 fatty acids against retinopathy,โ€ Dr Smith said. โ€By identifying the fatty acids, lipids and growth factors involved in both the disease and protective processes, we hope to translate this work to influence the outcome in patients. Our study results suggest that increasing omega-3 fatty acid intake in premature infants may significantly decrease the occurrence of ROP. This changing of lipids by dietary means may also translate to AMD and diabetic retinopathy. If clinical trials find that supplementing with omega-3 fatty acids is as effective in protecting humans against retinal disease as demonstrated by the findings of this study, this cost effective intervention could benefit millions of people."