News - February 8, 2011

ADHD symptoms disappear on diet

Children with ADHD benefit from a hypo-allergenic diet. After five weeks on the diet, 64 percent of them show no symptoms of ADHD.

This finding was reported by Wageningen immunologist Huub Savelkoul and veterinary epidemiologist Klaas Frankena in last week's Lancet. The researchers did a test which involved putting the children on the Restricted Elimination Diet (RED), which excludes all possible food allergens such as milk, peanuts, nuts, fish, wheat, soya and apples. This enabled the researchers to establish whether the children's behaviour was influenced by their diet. Later, they reintroduced these products one by one in order to find out which particular food the children reacted to.

Rating scale
There were already indications that young people with ADHD respond well to an elimination diet of this kind, but so far the tests were small-scale. This research team, made up of the Nijmegen university medical centre, the ADHD research centre in Eindhoven, Savelkoul and a child psychiatry organization, tackled it more thoroughly. A random group of 100 ADHD children was divided into a diet group and a control group. A paediatrician, who did not know which group each child belonged to, assessed their behaviour before and after the trial period using an ADHD rating scale. Teachers and parents also filled in a questionnaire before and after the trial period. In the control group, no change of behaviour was observed, whereas in the diet group the number of children with ADHD symptoms dropped by more than 60 percent.

Savelkoul, who helped set up the research and was responsible for the immunological analyses, analysed blood samples from the children in order to find out whether specific antibodies were present in their blood, or whether the pattern of antibodies had changed through the diet. He is enthusiastic about the results of the research. 'We have now established that you can change behaviour through diet. That has never been established so precisely for ADHD. It is good news for the children, because at present doctors routinely prescribe Ritalin, which loses effectiveness over time and can have serious side-effects. This research opens up the possibility for health insurance providers to cover nutritional interventions among children.'
That is still in the future, though. For now, Savelkoul's aim is wants to use the children's immune profile to make a crystal-clear diagnosis and determine objectively whether the treatment has an immunological effect as well. Almost eight percent of 4 to 17-year-olds in the Netherlands suffers from ADHD. And at least 40,000 of these children require treatment.