Low Blood Levels of DHA Omega-3 in Children Associated with Poor Cognitive Performance and Behaviour
Montgomery, P. et al., PLOS ONE, 8: in press, 2013
Centre for Evidence-Based Intervention, University of Oxford, Oxford, UK
DHA (docosahexaenoic acid) omega-3 fatty acid is known to support normal brain development and functioning. The present study measured the DHA levels in blood samples collected via finger-prick in 493 schoolchildren (ages 6-10 years) from mainstream schools as a biomarker of their DHA intakes and body status with respect to DHA. The children entered into the trial had no significant learning difficulty (not classified as having Special Educational Needs); however, their reading ability was below average according to national assessments. Reading and working memory in the children were measured by the British Ability Scales (II). Behaviour (ADHD-type symptoms) were scored using the revised Conners’ rating scales (long-parent and teacher versions).
After adjusting the results to control for gender and socio-economic status, the researchers found a statistically-significant relationship between DHA status of the children and performance. Those children with lower levels of circulating DHA exhibited both a poorer reading ability and working memory performance. Furthermore, a number of parent-reported behaviour problems (ADHD-type symptoms) were associated with a lower DHA status in the children. The authors concluded that the benefits reported in selected clinical trials from the literature with long-chain omega-3 fatty acid supplementation for ADHD, dyspraxia, dyslexia, and related conditions could possibly extend to the general school population.
Dr. Holub's Comments:
The low blood levels of DHA (the predominant omega-3 fatty acid found in most fish) reflect the low intake of fish (the main source of dietary DHA) by young children in the UK and in most countries. The vast majority (about 90 %) of the children in the present study failed to meet the UK guidelines of two fish portions per week. This research group presented the results of an intervention trial at the ISSFAL meeting (2012) wherein supplemental DHA was found to improve the reading ability of children who were scoring low on their reading ability. Dr. P. Montgomery was interviewed on site at this meeting by the DHA/EPA Omega-3 Institute. The summary of their findings and comments from Dr. Montgomery on this research (in collaboration with Dr. A. Richardson) can be found on this website (dhaomega3.org) by inserting the following into the search box in the upper right corner of the homepage: Richardson DHA . This latter study has since been published (PLOS ONE, vol. 17, 2013).