A recent study conducted at Rush University Medical Center in Chicago concludes that eating fish at least once a week slows age-related mental decline by the equivalent of three to four years.

    "We found that people who are one fish meal a week had a 10 percent slower annual decline in thinking," says co-author and epidemiologist Martha Clare Morris. "Those who are two fish meals a week showed a 13 percent slower annual decline."

    Simple cognitive test, conducted three times over a six-year period, were administered to 3,718 Chicago residents 65 and older. The participants also filled out a questionnaire about the foods they ate, which included four broad categories of seafood: tuna fish sandwiches; fish sticks, fish cakes or fish sandwiches; fresh fish as a main dish; and shrimp, lobster and crab.

    Previous studies have shown that fish consumption lowers the risk of Alzheimer's disease and stroke, and that fish rich in omega-3 fatty acids, such as tuna an salmon, prevents heart disease.

    The study can be found at the Archives of the Neurology Web site, http://archneur.amaassn.org/.