Sight for sure eyes: A study found that eating seafood lowered people's risk of age-related blindness.

RODALE NEWS, EMMAUS, PA—Researchers from Johns Hopkins University in Baltimore found that the more fish older people ate, the less likely they were to develop age-related macular degeneration (AMD), the leading cause of blindness and visual problems in most developed countries.

THE DETAILS: Researchers randomly chose 2,320 people aged 65 to 84, living on Maryland’s Eastern Shore, to complete a questionnaire designed to estimate how much seafood they ate each week. Researchers also examined the study participants for any signs of AMD, then correlated the association between seafood intake and the risk of AMD.

Taken as a whole, participants ate an average of 1.1 servings of fish or shellfish a week. But those with the greatest intake of seafood high in omega-3 fatty acids (oysters, crab, some kinds of fish) were 60 percent less likely to have advanced AMD than those who consumed less. Other studies have found similar results.

Interestingly, the researchers found no link between fish that are high in zinc (crab and oysters) and AMD risk. “This is in contrast to a large randomized clinical trial, the Age-Related Eye Disease Study (AREDS), which found that zinc intake reduced the risk of advanced AMD among those at high risk of this disease,” said study author Bonnielin Sceurman Swenor of the Wilmers Eye Institute at Johns Hopkins University in Baltimore. However, she noted, the AREDS study involved supplemental doses of zinc, far higher than the low dietary amounts those in her study got from fish.

The benefits of dietary omega-3 fatty acids could be due to high amounts of the fat found in the retina, Swenor said, which is thought to protect that part of the eye from injury.

WHAT IT MEANS: More than one serving a week of seafood high in omega-3 fatty acids such as tuna, salmon, crab, and oysters could reduce your risk of advanced AMD. However, Swenor said, her study doesn’t answer the question of exactly how much seafood is required.