Eating more fish may improve seniors' memory

By Joene Hendry

NEW YORK (Reuters Health) - Misplaced your keys? Can't place that face? Study findings suggest that you may be able to lessen the frequency of these "senior moments' simply by eating more fish. And the more fish you eat, the bigger the effect, according to research conducted in Norway.

Investigators found that elderly men and women who more frequently ate fish scored better on memory, visual conception, spatial motor skills, attention, orientation, and verbal fluency tests.

"All six cognitive tests were performed better by those who ate fish," principal author Dr. A. David Smith of the University of Oxford, UK, told Reuters Health. Furthermore, he added, the effect was stronger as fish consumption increased up to a limit of about 80 grams per day.

Smith and colleagues assessed cognitive ability and the average the daily amount of fish and seafood in the diets of 2,031 men and women, between 70 and 74 years old, recruited from the general population of Western Norway.

Overall, 1,951 of the study participants reported eating 10 or more grams per day of fresh, frozen, or canned fish and seafood, or fish products such as cod liver and fish oil, the investigators report in the American Journal of Clinical Nutrition. The remaining 80 participants ate less than 10 grams daily.

Study participants who reported more frequent consumption of fatty or lean fish as their main meal performed significantly better in five of the six cognitive tests, compared with those who did not eat fatty or lean fish.

Processed fish or fish sandwiches were likewise associated with better performance on three of the cognitive tests, the investigators note. By contrast, seniors who consumed only fish oils performed better on just one of the tests.

The investigators propose the need for additional research to determine whether the cognitive benefits from fish and seafood consumption depend on the type, the species of fish or on the preparation.

"Secondly, we need to discover what components of fish are important," Smith said. Since we found that lean fish was as good as fatty fish, it may not just be the omega-3 fatty acids that confer cognitive benefit, he commented.

SOURCE: American Journal of Clinical Nutrition, November 2007