Docosahexaenoic acid for reading, working memory and behavior in UK children aged 7-9: A randomized controlled trial for replication (the DOLAB II study)

Journal article

Background
Omega-3 fatty acids are central to brain-development of children. Evidence from clinical trials and systematic reviews demonstrates the potential of long-chain Omega-3 supplementation for learning and behavior. However, findings are inconclusive and in need of robust replication studies since such work is lacking.

Objectives
Replication of the 2012 DOLAB 1 study findings that a dietary supplementation with the long-chain omega-3 docosahexaenoic acid (DHA) had beneficial effects on the reading, working memory, and behavior of healthy schoolchildren.

Design
Parallel group, fixed-dose, randomized (minimization, 30% random element), double-blind, placebo-controlled trial (RCT).

Setting
Mainstream primary schools (n = 84) from five counties in the UK in 2012–2015.

Participants
Healthy children aged 7–9 underperforming in reading (<20th centile). 1230 invited, 376 met study criteria.

Intervention
600 mg/day DHA (from algal oil), placebo: taste/color matched corn/soybean oil; for 16 weeks.

Main outcome measures
Age-standardized measures of reading, working memory, and behavior, parent-rated and as secondary outcome teacher-rated.

Results
376 children were randomized. Reading, working memory, and behavior change scores showed no consistent differences between intervention and placebo group. Some behavioral subscales showed minor group differences.

Conclusions
This RCT did not replicate results of the earlier DOLAB 1 study on the effectiveness of nutritional supplementation with DHA for learning and behavior. Possible reasons are discussed, particularly regarding the replication of complex interventions.

Authors: Montgomery, P; Spreckelsen, T; Burton, A; Burton, J; Richardson, A

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Public Library of Science
• Journal: PLoS One
• Volume: 13
• Issue: 2
• Article number: e0192909
• Publication date: 2018-02-20
• Acceptance date: 2018-01-04
• DOI: 10.1371/journal.pone.0192909
• EISSN: 1932-6203
• ISSN: 1932-6203
• Pmid: 29462158
• Language: English
• Keywords: omega-3; working memory; nutrition; reading; pufa; randomised controlled trial; fatty acids; polyunsaturated fatty acids; food supplementation; schools; children; behaviour; learning; dha; adhd; replication; rct