Effect of fish oil on cognitive performance in older subjects: a randomized, controlled trial.
BACKGROUND
High intake of n-3 polyunsaturated fatty acids may protect against age-related cognitive decline. However, results from epidemiologic studies are inconclusive, and results from randomized trials in elderly subjects without dementia are lacking.


OBJECTIVE
To investigate the effect of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) supplementation on cognitive performance.


METHODS
Double-blind, placebo-controlled trial involving 302 cognitively healthy (Mini-Mental State Examination score > 21) individuals aged 65 years or older. Participants were randomly assigned to 1,800 mg/d EPA-DHA, 400 mg/d EPA-DHA, or placebo capsules for 26 weeks. Cognitive performance was assessed using an extensive neuropsychological test battery that included the cognitive domains of attention, sensorimotor speed, memory, and executive function.


RESULTS
The mean age of the participants was 70 years, and 55% were male. Plasma concentrations of EPA-DHA increased by 238% in the high-dose and 51% in the low-dose fish oil group compared with placebo, reflecting excellent compliance. Baseline scores on the cognitive tests were comparable in the three groups. Overall, there were no significant differential changes in any of the cognitive domains for either low-dose or high-dose fish oil supplementation compared with placebo.


CONCLUSIONS
In this randomized, double-blind, placebo-controlled trial, we observed no overall effect of 26 weeks of eicosapentaenoic acid and docosahexaenoic acid supplementation on cognitive performance.
van de Rest
O
O
Wageningen University, Division of Human Nutrition, P.O. Box 8129, 6700 EV, Wageningen, The Netherlands. ondine.vanderest@wur.nl
Geleijnse
J M
JM
Kok
F J
FJ
van Staveren
W A
WA
Dullemeijer
C
C
Olderikkert
M G M
MG
Beekman
A T F
AT
de Groot
C P G M
CP
D000368:Aged; D002214:Capsules; D003071:Cognition; D003072:Cognition Disorders / Q000517:prevention & control*; D019587:Dietary Supplements; D004311:Double-Blind Method; D015118:Eicosapentaenoic Acid / Q000008:administration & dosage*; D005231:Fatty Acids, Unsaturated / Q000008:administration & dosage*; D005260:Female; D005395:Fish Oils / Q000008:administration & dosage*; D006801:Humans; D008297:Male
D002214:Capsules; D005231:Fatty Acids, Unsaturated; D005395:Fish Oils; D015118:Eicosapentaenoic Acid; C026219:docosapentaenoic acid