Michelle Berriedale-Johnson reports

Scarily, it is now accepted that one in every five children in the US and the UK suffers from some level of developmental disorder, from reading problems to full blown ADHD or Autistic Spectrum Disorders, and that many of those children will carry their behavioural problems with them into adulthood.

Equally scarily, but maybe not surprisingly in view of the above, it is also now accepted that mental health/behavioural problems are the fastest growing area of ill health within the adult population, even now costing the NHS more than coronary heart disease and cancer combined.

Although the link between nutrition and mental health does not feature largely in the conventional approach to mental health issues, either in children or in adults, it is widely accepted:

• That the human brain is made up of 60% fat and that the Omega 3 Highly Unsaturated Fatty Acid DHA (docosahexaenoic acid) is the primary structural component not only of the human brain but of the retina; the fatty acid EPA (eicosapentaenoic acid) is essential for inter-cellular communication.

• That the ideal balance for human nutrition of Omega 3 and Omega 6 fatty acids is probably around 1 to 1, but that modern western societies consume up to 15 times more pro-inflammatory Omega 6 fatty acid than they do anti-inflammatory Omega 3 fatty acids.

• That fish, especially oily fish, is almost the only real source of Omega 3s, especially DHA and EPA, and that our consumption of fish has plummeted over the last 100 years. (Over 90% of the children in the DOLAB study did not meet even the minimal dietary guidelines for fish consumption while their blood levels of Omega 3s was significantly below the 'high risk level' for cardiovascular disease set for adults.)

Fish oil supplementation and behaviour

In 2005 the Oxford Durham study found that raising the children's intake of Omega 3s by supplementation with fish oils could be both a safe and efficacious way of treating children with behavioural disorders. But they had had no way of validating their conclusion by objectively measuring the levels of Omega 3 in the children's blood before and after treatment as it would have been ethically unacceptable to take blood samples from the children in the usual way.

Moreover, although fish oil supplementation appeared to be effective with children with specific behavioural problems, they had no idea whether raising the intake of Omega 3s in 'normal' children with no behavioural problems might be effective in terms of improving their mental acuity in terms of, for example, reading skills and working memory. However, thanks to the introduction of a finger prick blood test, the new DOLAB studies have been able to address both of these points.

The study set out to establish whether a measurable increasein the blood levels of Omega 3 DHA could affect a group a 'normal' 7–9 year-olds which included 'poor readers'.

Screening

• Chosen for screening were 493 school children, between 7 and 9 years of age, from 74 schools around Oxfordshire.
• The reading skills of two thirds of the children were below the average for their age when assessed by normal Key Stage 1 tests.
• Nearly 90% were reported to eat less that two portions of fish or seafood per week and their blood concentrations of DHA/EPA (at 2.46%, significantly below the high risk level for cardiovascular disease in adults) correlated with their intake of fish.
• Controlling for sex and socioeconomic status, lower levels of DHA in the blood correlated with poorer reading skins, poorer working memory and worse general behaviour rates on a number of standard tests.

The researchers make the point that this study was purely observational so cannot address causality; further studies are obviously needed. However they do suggest that there could be a significant benefit for the whole school population in extending dietary supplementation with Omega 3 long chain fatty acids.

The DOLAB intervention study

The participants were 362 children drawn from the screening group of 493 7 to 9 year olds.

To be eligible the children had to:

• Be below the 33rd centile in reading skills
• To have English as their first language
• Not to suffer from any major medical conditions or learning difficulties
• To eat less than two portions of fish per week
• Not to be taking any Omega 3 supplements or any medication which could be expected to affect their learning skills or behaviour.

They were then randomised to receive either 600ml per day of DHA (from an algal source) or an identical looking/tasting corn/soyabean capsule for 16 weeks.

Results:

The supplementation did not have an affect on the group as a whole but, it did have a very significant affect on the worse readers amongst the group.

Among 224 children who were below the 20th centile for their reading, reading performance improved by 20% relative to the children on the placebo tablets; for the children with the worst reading skills, those below the 10th centile, the improvement was even more dramatic at 50%.

Working memory improved very much in line with reading skills, the most dramatic improvement being in the children with the poorest working memory.

In terms of behaviour, there was a general improvement in behaviour as a result of the placebo effect, but this improvement was more marked in the lower reading group.

The full study is available here on PLOS1 – Docosahexaenoic Acid for Reading, Cognition and Behavior in Children Aged 7–9 Years: A Randomized, Controlled Trial (The DOLAB Study). Alexandra J. Richardson, Jennifer R. Burton, Richard P. Sewell, Thees F. Spreckelsen, Paul Montgomery

Sleep and Omega 3s

Professor Paul Montgomery, one of the authors of the DOLAB study is also an authority on sleep problems in children and so, included in the study, were some simple assessments of children's sleep in both the screening and the trial process. As Professor Montgomery points out, their findings have not yet been subjected to peer review so can only be regarded as exploratory.

None the less their preliminary findings do suggest that there may also be significant associations between Omega 3 status and sleep problems in children and that these may be impacted by DHA supplementation.

Sleep problems are already associated with poor mental and physical health, with behaviour problems and with performance but, to date, there has been little investigation of the links between sleep and fatty acid status in either adults or children.

The DOLAB trials will, hopefully, be a significant step forward in the recognition by the mainstream medical fraternity of the vital role that Omega 3 fatty acids play in children's development – if for no other reason than that they provide the first objective blood tests supporting the claims that have long been made for fatty acid supplementation.

They are certainly a tribute to the tireless work of Dr Alex Richardson and her FABResearch team in this area and will hopefully provide the springboard for some genuinely effective interventions. Although how such interventions should be implemented is a whole other question. For a discussion of the practical, environmental and ethical dilemmas thrown up by the concept of increasing population-wide consumption of Omega 3 fatty acids.

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