Omega-3 fatty acids may prevent retinopathies, study suggests

Increasing dietary omega-3 fatty acids protected against the development and progression of retinopathy in a study involving mice. The finding may have implications for managing retinal diseases in humans, including retinopathy of prematurity and diabetic retinopathy, investigators noted.

Researchers from institutions including Massachusetts General Hospital, Children's Hospital Boston and the National Eye Institute (NEI) analyzed the effects of the omega-3 fatty acids EPA and DHA and the omega-6 fatty acid arachidonic acid on loss of blood vessels, regrowth of healthy vessels and growth of destructive abnormal vessels in a mouse model of oxygen-induced retinopathy. Their results are published in the July issue of Nature Medicine.

Investigators found that an increased intake of omega-3 fatty acids and a decreased intake of omega-6 fatty acids reduced the area of vessel loss causing the growth of abnormal vessels and blindness, according to a press release from the NEI.

Further supporting the findings, the researchers studied mice fed a diet higher in omega-3 fatty acids than in omega-6 fatty acids and compared them with mice fed a diet with lower amounts of omega-3 fatty acids. They also studied mice genetically altered to convert omega-6 fatty acids to omega-3 fatty acids.

The researchers found close to a 50% decrease in retinopathy in mice fed higher amounts of omega-3, according to the release.

"Our findings represent new evidence suggesting the possibility that omega-3 fatty acids act as protective factors in diseases that affect retinal blood vessels," said John Paul SanGiovanni, ScD, an NEI staff scientist and an author of the study, in the release. "This is a major conceptual advance in the effort to identify modifiable factors that may influence inflammatory processes implicated in the development of common sight-threatening retinal diseases."

Dr. SanGiovanni also emphasized the biological support these findings lend to findings from human studies on diet and retinal disease.

Lois E. H. Smith, MD, PhD, a senior investigator of the study and associate professor of ophthalmology at Children's Hospital Boston, said the results could have implications for many patients, including infants with retinopathy of prematurity (ROP).

"Our study results suggest that increasing omega-3 fatty acid intake in premature infants may significantly decrease the occurrence of ROP," Dr. Smith said in the release. "This changing of lipids by dietary means may also translate to [age-related macular degeneration] and diabetic retinopathy."

The NEI is currently analyzing the effect of the omega-3 fatty acids DHA and EPA on the progression of AMD as part of the Age-Related Eye Disease Study 2. Researchers at Children's Hospital Boston are also planning a trial testing the effects of omega-3 supplements in premature infants.