The symptoms of ADHD in children can be reduced drastically by five weeks on a strict diet. In collaboration with the ADHD Research Centre in Eindhoven and Rotterdam-based paediatrician Rob Pereira, Wageningen researchers are going to find out why that is.
The researchers are going to measure the effects of a very frugal diet on a wide range of blood and urine values, the composition of the gut flora, the immune system and the brain activity of children with ADHD. The restricted elimination diet (RED) is put together for each child individually but always includes rice, lamb, turkey, vegetables and fruit, supplemented with vitamins and minerals. In the INCA study, published in The Lancet in 2011, the behaviour of around 60 percent of the participating children improved radically on this diet.
In the new study, which will take six years, the scientists are going to investigate the differences between children who do benefit from the elimination diet and those who do not. Firstly, blood, urine and faeces samples from 60 or so children on the diet will be analysed, and MRI scans will be made. A larger study will follow, based on the results of the smaller study.
The Wageningen researchers involved, who work in the Host-microbe interactomics and the Quantitative veterinary epidemiology chair groups, will focus on changes in the gut flora, the metabolism and the immune system response.
‘It is a very legitimate assumption that gut bacteria play a role,’ says researcher Peter van Baarlen.‘Gut bacteria can make sulphur compounds from food, for instance, which are released into the blood and can reach the brain. We are going to see whether certain bacteria are present, or indeed absent, in the children who respond well to this diet.’ The Wageningen researchers will also measure differences in gene expression.
Van Baarlen hopes the research results will lead to a test with which it can be established quickly and easily whether a child with ADHD stands to benefit from a diet, and which foodstuffs the child should avoid.