Restricted elimination diet may indicate if food involved with ADHD

January 01, 0001

Restricted elimination diet may indicate if food involved with ADHD

The researchers from The Netherlands aimed to investigate whether there is a connection between diet and behaviour in an unselected group of children. The Impact of Nutrition on Children with ADHD (INCA) study was a randomised controlled trial that consisted of an open-label phase with masked measurements followed by a double-blind crossover phase. Randomisation in both phases was individually done by random sampling. In the open-label phase (first phase), children aged 4—8 years who were diagnosed with ADHD were randomly assigned to 5 weeks of a restricted elimination diet (diet group) or to instructions for a healthy diet (control group). Between Nov 2008, and Sept 2009, 100 children were enrolled and randomly assigned to the control group (n=50) or the diet group (n=50).

Between baseline and the end of the first phase, the difference between the diet group and the control group in the mean ARS total score was 23.7 (significant) according to the masked ratings. The difference between groups in the mean ACS score between the same timepoints was 11.8 (significant). The ARS total score increased in clinical responders after the challenge by 20.8 (significant) and the ACS score increased by 11.6 (significant). In the challenge phase, after challenges with either high-IgG or low-IgG foods, relapse of ADHD symptoms occurred in 63% children, independent of the IgG blood levels. There were no harms or adverse events reported in both phases.

The researchers concluded: "A strictly supervised restricted elimination diet is a valuable instrument to assess whether ADHD is induced by food. The prescription of diets on the basis of IgG blood tests should be discouraged."

There are a number of issues here including selection and proper blinding.

For the full abstract, click here.

The Lancet 377(9764):494-503, 5 February 2011
© 2011 Elsevier Limited
Effects of a restricted elimination diet on the behaviour of children with attention-deficit hyperactivity disorder (INCA study): a randomised controlled trial. Lidy M Pelsser, Klaas Frankena, Jan Toorman et al. Correspondence to Lidy Pelsser:

Category: T. Endocrine/Metabolic/Nutritional. Keywords: restricted elimination diet, behaviour, children, attention-deficit hyperactivity disorder, randomised controlled trial, journal watch.
Synopsis edited by Dr Stephen Wilkinson, Melbourne, Australia. Posted on Global Family Doctor 27 May 2011

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