Fatty Fish May Cut Risk of Macular Degeneration

March 14, 2011 -- Eating fatty fish one or more times a week may reduce your risk for developing age-related macular degeneration, a leading cause of vision loss in people aged 60 and older. 

The new findings appear online in the Archives of Opthalmology.

About 9 million Americans aged 40 and older show signs of age-related macular degeneration (AMD) and 7.3 million more people have an early form of this potentially vision-robbing disease.

AMD targets the part of the eye that allows you to focus in on details (the macula). The disease destroys the sharp, central vision needed to see objects clearly, read, and drive. In some people the disease progresses slowly; in others, a faster progression can lead to vision loss in both eyes.

Women in the new study who got the highest amounts of docosahexaenoic acid (DHA), an omega-3 fatty acid found in fish, were 38% less likely to develop AMD than women who got the least DHA. Similar findings were seen regarding the highest consumption levels of eicosapentaenoic acid (EPA), another omega-3 found in fatty fish.

What’s more, women who ate one or more servings of fatty fish per week -- mainly canned tuna and dark-meat fish --  were 42% less likely to be diagnosed with AMD compared with women who ate fish less than once a month.  

Salmon, trout, and sardines are also loaded with omega-3 fatty acids.

Role of Inflammation in AMD

Exactly how fatty fish and omega-3s may help reduce risk for AMD is not fully understood. But some research suggests that chronic inflammation may play a role in causing AMD. “Omega-3 fish oils are believed to have anti-inflammatory properties, so it’s plausible that these anti-inflammatory properties could be of benefit,” says study researcher William G. Christen, ScD, an associate professor of medicine at Brigham and Women’s Hospital and Harvard Medical School in Boston.

Using data from the Women’s Health Study, researchers analyzed the diets of 38,022 women with an average age of 54 who had not been diagnosed with AMD. During 10 years of follow-up, there were 235 cases of AMD reported.

“Among those people who really don’t have much AMD to begin with, the omega-3 fatty acids DHA and EPA and fish intake may help prevent future development of AMD,” Christen says. “Fish and fish oils may be of benefit in the primary prevention of AMD.”

More research is needed to confirm these findings, he says.

AMD Prevention

Jack Cohen, MD, an ophthalmologist at Rush University Medical Center in Chicago, says that if omega-3 fatty acids could prevent AMD from occurring it would be “amazing.”

The new study “does show potential for prevention and that is where AMD research is the weakest,” he says.