Research Review
Research Review: The role of diet in the treatment of attention-deficit/hyperactivity disorder – an appraisal of the evidence on efficacy and recommendations on the design of future studies
Jim Stevenson,
Jan Buitelaar,
Samuele Cortese,
Maite Ferrin, Eric Konofal,
Michel Lecendreux,
Emily Simonoff,
Ian C. K. Wong,
Edmund Sonuga-Barke,
on behalf of the European ADHD Guidelines Group,
Corresponding Author
Jim Stevenson
Department of Psychology, Developmental Brain-Behaviour Laboratory, University of Southampton, Southampton, UK
Correspondence
Jim Stevenson, Developmental Brain-Behaviour Laboratory, Psychology, University of Southampton, Highfield, Southampton SO17 1BJ, UK; Email: [email protected]
Search for more papers by this authorJan Buitelaar
Department of Cognitive Neuroscience and Karakter Child and Adolescent Psychiatry University Centre, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
Search for more papers by this authorSamuele Cortese
Phyllis Green and Randolph Cowen Institute for Pediatric Neuroscience, Child Study Center of the NYU Langone Medical Center, New York, NY, USA
Child Neuropsychiatry Unit, Department of Life Sciences and Reproduction, Verona University, Verona, Italy
Search for more papers by this authorEric Konofal
Pediatric Sleep Center, National Reference Network for Orphan Diseases (Narcolepsy Idiopathic Hypersomnia and Kleine-Levin Syndrome), Robert Debré Hospital, Paris, France
Search for more papers by this authorMichel Lecendreux
Pediatric Sleep Center, National Reference Network for Orphan Diseases (Narcolepsy Idiopathic Hypersomnia and Kleine-Levin Syndrome), Robert Debré Hospital, Paris, France
Search for more papers by this authorEmily Simonoff
Department of Child and Adolescent Psychiatry and NIHR Biomedical Research Centre for Mental Health, Institute of Psychiatry, King's College London, London, UK
Search for more papers by this authorIan C. K. Wong
Department of Pharmacology and Pharmacy, University of Hong Kong, Hong Kong
Search for more papers by this authorEdmund Sonuga-Barke
Department of Psychology, Developmental Brain-Behaviour Laboratory, University of Southampton, Southampton, UK
Department of Experimental Clinical and Health Psychology, Ghent University, Ghent, Belgium
Search for more papers by this authorthe European ADHD Guidelines Group
Search for more papers by this authorJim Stevenson,
Jan Buitelaar,
Samuele Cortese,
Maite Ferrin, Eric Konofal,
Michel Lecendreux,
Emily Simonoff,
Ian C. K. Wong,
Edmund Sonuga-Barke,
on behalf of the European ADHD Guidelines Group,
Corresponding Author
Jim Stevenson
Department of Psychology, Developmental Brain-Behaviour Laboratory, University of Southampton, Southampton, UK
Correspondence
Jim Stevenson, Developmental Brain-Behaviour Laboratory, Psychology, University of Southampton, Highfield, Southampton SO17 1BJ, UK; Email: [email protected]
Search for more papers by this authorJan Buitelaar
Department of Cognitive Neuroscience and Karakter Child and Adolescent Psychiatry University Centre, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
Search for more papers by this authorSamuele Cortese
Phyllis Green and Randolph Cowen Institute for Pediatric Neuroscience, Child Study Center of the NYU Langone Medical Center, New York, NY, USA
Child Neuropsychiatry Unit, Department of Life Sciences and Reproduction, Verona University, Verona, Italy
Search for more papers by this authorEric Konofal
Pediatric Sleep Center, National Reference Network for Orphan Diseases (Narcolepsy Idiopathic Hypersomnia and Kleine-Levin Syndrome), Robert Debré Hospital, Paris, France
Search for more papers by this authorMichel Lecendreux
Pediatric Sleep Center, National Reference Network for Orphan Diseases (Narcolepsy Idiopathic Hypersomnia and Kleine-Levin Syndrome), Robert Debré Hospital, Paris, France
Search for more papers by this authorEmily Simonoff
Department of Child and Adolescent Psychiatry and NIHR Biomedical Research Centre for Mental Health, Institute of Psychiatry, King's College London, London, UK
Search for more papers by this authorIan C. K. Wong
Department of Pharmacology and Pharmacy, University of Hong Kong, Hong Kong
Search for more papers by this authorEdmund Sonuga-Barke
Department of Psychology, Developmental Brain-Behaviour Laboratory, University of Southampton, Southampton, UK
Department of Experimental Clinical and Health Psychology, Ghent University, Ghent, Belgium
Search for more papers by this authorthe European ADHD Guidelines Group
Search for more papers by this authorConflict of interest statement: Disclosures of interest declared in Acknowledgement section.
Abstract
Background
The efficacy of three dietary treatments for ADHD has been repeatedly tested in randomized controlled trials (RCTs). These interventions are restricted elimination diets (RED), artificial food colour elimination (AFCE) and supplementation with free fatty acids (SFFA). There have been three systematic reviews and associated meta-analyses of the RCTs for each of these treatments.
Scope
The aim of this review is to critically appraise the studies on the dietary treatments of ADHD, to compare the various meta-analyses of their efficacy that have been published and to identify where the design of such RCTs could be improved and where further investigations are needed.
Findings
The meta-analyses differ in the inclusion and exclusion criteria applied to potentially eligible studies. The range of average effect sizes in standard deviation units is RED (0.29–1.2), AFCE (0.18–0.42) and SFFA (0.17–0.31). The methodology of many of the trials on which the meta-analyses are based is weak.
Conclusions
Nevertheless, there is evidence from well-conducted studies for a small effect of SFFA. Restricted elimination diets may be beneficial, but large-scale studies are needed on unselected children, using blind assessment and including assessment of long-term outcome. Artificial food colour elimination is a potentially valuable treatment but its effect size remains uncertain, as does the type of child for whom it is likely to be efficacious. There are additional dietary supplements that have been used with children with ADHD. A systematic search identified 11 RCTs that investigated the effects of these food supplements. Despite positive results for some individual trials, more studies are required before conclusions can be reached on the value in reducing ADHD symptoms of any of these additional supplements.
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