Eating fish that's rich in omega-3 fatty acids may help reduce the risk for age-related macular degeneration (AMD), which is a leading cause of blindness in seniors. The study adds to a growing body of evidence regarding the wide variety of health benefits of these friendly fats.

Those who ate at least one serving of omega-3-rich fish per week were 60% less likely to have advanced AMD than people who ate less than one serving per week.

In the current study researchers gave food questionnaires to 2,520 seniors living in the coastal town of Salisbury, Maryland. Among the questions were some that determined how frequently the participants ate various kinds of fish over the past year: for example, "fried fish (fried fish/fish sandwich), oysters (oyster fritters/fried oysters), tuna (tuna fish/tuna salad/tuna casserole), shellfish (shrimp or lobster), crab (crab/crab cakes/crab salad), and "other fish" (other fish baked or fried)". Whether the patients suffered from AMD was determined by a examining the patients' eyes and looking for the telltale signs of the disease.

The Johns Hopkins University team, led by Bonnielin K. Swenor, found that although there were no associations between seafood consumption in general and AMD, when they broke things down, they found that people who ate the most fish rich in omega-3's did seem to have less risk of advanced AMD. In particular, those who ate at least one serving of omega-3-rich fish per week were 60% less likely to have advanced AMD than people who ate less than one serving per week. The authors conclude by saying that this "study of older participants found a protective effect for advanced AMD with intake of fish and shellfish high in omega-3 fatty acids."

Is it possible that people who ate more omega-3-rich fish led healthier lifestyles in general, and this contributed to the reduced risk of AMD? Unlikely, the authors say, because of where the study took place: "fish and shellfish eating in Salisbury is not perceived as a "healthy" lifestyle, but rather a consequence of easy access to this ready source of protein. In fact, both smoking and BMI increase with increasing consumption of fish/shellfish in this population, suggesting if anything an inverse relation of healthy living with fish consumption in this [group]."

Future research will have to tease apart the connection between omega-3's and eye disease, but in the meantime, given the other potential health benefits of the fatty acids, including cancer and heart disease prevention, it probably won't hurt to indulge in a little healthy fish every now and again.

The new study was published in the July 13, 2010 issue of the journal Ophthalmology.