BACKGROUND: In humans, n-3 long-chain polyunsaturated fatty acids play a well-documented role in brain development and function. Docosahexaenoic acid and arachidonic acid are major structural components of the brain and a deficiency thereof may bring about changes in the behaviour domains of the brain.

OBJECTIVE: This trial investigated the effect of an experimental fish-flour bread spread rich in n-3 long-chain polyunsaturated fatty acids, on cognition of children (7-9yr).

DESIGN: Subjects (n=183) were randomly assigned to an experimental (n=91) and control group (n=92), receiving either the fish-flour spread or a placebo spread for 6 months in a single-blind study. Plasma and red blood cell phospholipid fatty acid composition and cognition were measured at baseline and post-intervention.

RESULTS: After the intervention, eicosapentaenoic and docosahexaenoic acid levels were significantly higher in the experimental group compared to the control group (p< 0.0001). Significant intervention effects were also observed for the Hopkins Verbal Learning Test Recognition (estimated effect size: 0.80; 95% confidence interval (CI): 0.15; 1.45) and Discrimination Index (estimated effect size: 1.10; 95% CI: 0.30; 1.91), as well as the Spelling test (estimated effect size: 2.81; 95% CI: 0.59; 5.02) by both per protocol and intention to treat analyses. A marginally significant (p=0.0646) effect was observed for the Reading test (estimated effect size: 2.21; 95% CI: -0.14; 4.56) only in the per protocol analysis.

CONCLUSION: This study suggests improvement of verbal learning ability and memory of children when supplemented with a fish-flour spread rich in n-3 long-chain polyunsaturated fatty acids.