New research published in the July edition of the Journal of Nutritional Biochemistry has established a strong correlation between blood levels of omega-3s, especially docosahexaenoic acid (DHA), and better brain function in children 2–6 years old
The objective of this cross-sectional study was to investigate the relationship between whole-blood fatty acids (FAs) and executive function in 307 children (2–6 years old) from Northern Ghana.
The aim of researchers was to examine the extent to which higher levels of EPA and/or DHA were associated with better cognitive performance. Dried blood spot samples were collected and analysed for FA content.
The children underwent a battery of age-appropriate cognitive function tests. Specifically, the dimensional change card sort (DCCS) task was used to assess executive function.
The DCCS asks that the child sort a series of bivalent cards based on one of two instructed dimensions (either colour or shape). Following sorting an initial series of eight cards based on colour, the child is instructed to switch the categorisation dimension and sort another series of eight cards based on shape.
This dimensional change in sorting behaviour provides an index of executive function as the child must suppress their previously learned set of rules (sorting by colour) and attentional inertia towards those attributes to flexibly adjust their behavioural actions and attention to sort the cards by a new set of rules (sorting by shape).
The average Omega-3 Index (red blood cell EPA + DHA level) in this group was 4.6%, with a range of 2.3–11.7%. Significant differences in mean % total whole-blood fatty acids were observed between children who could not follow directions on the DCCS test (50% of the sample) and those who could (50% of the sample).
Children with the highest levels of total omega-3s and DHA were three and four times, respectively, more likely to pass at least one condition of the DCCS test of executive function than those with the lowest levels.
This study has several strengths. First and foremost, it utilised an objective biomarker to assess dietary fatty acid intake (the Omega-3 Index), as opposed to other conventional and less precise methods such as food frequency questionnaires or diet history techniques.
Food frequency questionnaires are not highly accurate at estimating circulating blood levels of fatty acids. The authors concluded that these findings provided an “impetus for further studies into possible interventions to improve essential fatty acid status of children in developing countries.”
One of the study’s investigators, Dr Bill Harris, founder of OmegaQuant and co-inventor of the Omega-3 Index test, said the results are very encouraging for these children, who are probably the most disadvantaged when it comes to omega-3 consumption.
“Children in developing countries such as Ghana do not have the access to omega-3-rich sources that children from other parts of the world do. This has several ramifications, particularly in the area of brain development and cognitive function."
"We were happy to see the positive correlation between omega-3 levels and better brain function, especially as an omega-3 deficiency is so easy to correct. All it requires is consuming more of the right omega-3s, especially DHA, which in this case, was the standout fatty acid here.”