Quick Study

Quick Study: Fish oil may not improve the mental functioning of older people

Tuesday, May 18, 2010


Fish oil supplements may not improve the mental functioning of older people

THE QUESTION People sometimes take fish oil supplements, hoping to stave off dementia or even improve their cognitive abilities late in life. Does this help?

THIS STUDY randomly assigned 867 adults in their 70s with no signs of cognitive decline to take fish oil supplements -- two omega-3 fatty acids: EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) -- or placebo pills daily for two years. Participants' thinking and memory skills were evaluated through cognitive tests given at the start and end of the study. After the two years, blood tests showed higher concentrations of EPA and DHA among people who took the supplements than among the others. However, neither group experienced a drop in cognitive functioning, and virtually no cognitive differences were found between those who did and did not take fish oil supplements.

WHO MAY BE AFFECTED? Older people. At some point in the aging process, people usually experience mild memory loss and some slowing of information processing. This is considered normal and is not related to dementia, a brain disorder that impairs mental functioning to the point that it interferes with daily functioning.

CAVEATS The authors suggested that the study might have been too short to detect possible benefits. Most participants were found to be highly functioning, cognitively, at the start of the study; whether people with mild cognitive impairment would have fared differently was not tested.

FIND THIS STUDY April 21 online issue of the American Journal of Clinical Nutrition.

LEARN MORE ABOUT age-related memory loss at http://www.familydoctor.com. Learn about fish oil at http://www.mayoclinic.com (search for "omega-3 fatty acids").

-- Linda Searing

The research described in Quick Study comes from credible, peer-reviewed journals. Nonetheless, conclusive evidence about a treatment's effectiveness is rarely found in a single study. Anyone considering changing or beginning treatment of any kind should consult with a physician.

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