Free Access
Dement Geriatr Cogn Disord 2006;21:88–96
(DOI:10.1159/000090224)

The Efficacy of Omega–3 Fatty Acids on Cognitive Function in Aging and Dementia: A Systematic Review

Issa A.M.a, b · Mojica W.A.a · Morton S.C.a · Traina S.a, b, c · Newberry S.J.a · Hilton L.G.a · Garland R.H.a · MacLean C.H.a, c, d
The Southern California Evidence-Based Practice Center –aRAND Health, Santa Monica, Calif., Schools of bPublic Health and cMedicine, University of California, dThe Greater Los Angeles VA Medical Center, Los Angeles, Calif., USA
email Corresponding Author


 goto top of outline Key Words

  • Omega–3 fatty acids
  • Treatment of dementia
  • Alzheimer’s disease
  • Cognitive function in normal aging

 goto top of outline Abstract

We systematically reviewed the published literature on the effects of omega–3 fatty acids on measures of cognitive function in normal aging, incidence and treatment of dementia. Computerized databases were searched for published literature to identify potentially relevant studies with the intent to conduct a meta-analysis. We screened 5,865 titles, reviewed 497 studies of which 49 underwent a detailed review, and found 5 studies that pertained to our objectives. We included controlled clinical trials and observational studies, including prospective cohort, case-control, and case series designs; we excluded case reports. We had no language restrictions. We abstracted data on the effects of omega–3 fatty acids and on study design, relevant outcomes, study population, source, type, amount, and duration of omega–3 fatty acid consumption, and parameters of methodological quality. A single cohort study has assessed the effects of omega–3 fatty acids on cognitive function with normal aging and found no association for fish or total omega–3 consumption. In four studies that assessed the effects of omega–3 fatty acids on incidence and treatment of dementia, a trend in favor of omega–3 fatty acids (fish and total omega–3 consumption) toward reducing risk of dementia and improving cognitive function was reported. The available data are insufficient to draw strong conclusions about the effects of omega–3 fatty acids on cognitive function in normal aging or on the incidence or treatment of dementia. However, limited evidence suggests a possible association between omega–3 fatty acids and reduced risk of dementia.

Copyright © 2006 S. Karger AG, Basel


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 goto top of outline Author Contacts

Amalia M. Issa, MPH, PhD
RAND Corporation Division of Health
1776 Main Street
Santa Monica, CA 90401 (USA)
E-Mail aissa1@ucla.edu


 goto top of outline Article Information

The views expressed in this article are those of the authors and do not necessarily reflect those of the Agency for Healthcare Research and Quality or the U.S. Department of Health and Human Services.

Accepted after revision: September 7, 2005
Published online: December 9, 2005
Number of Print Pages : 9
Number of Figures : 1, Number of Tables : 5, Number of References : 23


 goto top of outline Publication Details

Dementia and Geriatric Cognitive Disorders

Vol. 21, No. 2, Year 2006 (Cover Date: January 2006)

Journal Editor: Chan-Palay, V. (New York, N.Y.)
ISSN: 1420–8008 (print), 1421–9824 (Online)

For additional information: http://www.karger.com/DEM


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