Millichap JG, Yee MM. (2012) Pediatrics. Jan 9. [Epub ahead of print]
This article is intended to provide a comprehensive overview of the role of dietary methods for treatment of children with attention-deficit/hyperactivity disorder (ADHD) when pharmacotherapy has proven unsatisfactory or unacceptable.
Results of recent research and controlled studies, based on a PubMed search, are emphasized and compared with earlier reports. The recent increase of interest in this form of therapy for ADHD, and especially in the use of omega supplements, significance of iron deficiency, and the avoidance of the "Western pattern" diet, make the discussion timely.
Diets to reduce symptoms associated with ADHD include sugar-restricted, additive/preservative-free, oligoantigenic/elimination, and fatty acid supplements. Omega-3 supplement is the latest dietary treatment with positive reports of efficacy, and interest in the additive-free diet of the 1970s is occasionally revived. A provocative report draws attention to the ADHD-associated "Western-style" diet, high in fat and refined sugars, and the ADHD-free "healthy" diet, containing fiber, folate, and omega-3 fatty acids.
The literature on diets and ADHD, listed by PubMed, is reviewed with emphasis on recent controlled studies. Recommendations for the use of diets are based on current opinion of published reports and our practice experience.
Indications for dietary therapy include medication failure, parental or patient preference, iron deficiency, and, when appropriate, change from an ADHD-linked Western diet to an ADHD-free healthy diet. Foods associated with ADHD to be avoided and those not linked with ADHD and preferred are listed.
In practice, additive-free and oligoantigenic/elimination diets are time-consuming and disruptive to the household; they are indicated only in selected patients. Iron and zinc are supplemented in patients with known deficiencies; they may also enhance the effectiveness of stimulant therapy. In patients failing to respond or with parents opposed to medication, omega-3 supplements may warrant a trial.
A greater attention to the education of parents and children in a healthy dietary pattern, omitting items shown to predispose to ADHD, is perhaps the most promising and practical complementary or alternative treatment of ADHD.
This important and timely article provides a comprehensive review of research into nutritional approaches to the management of ADHD, and provides some sensible, evidence-based guidelines for practitioners and parents.
The authors acknowledge the evidence that some children may be helped by special diets (e.g. eliminating specific foods or additives), or by supplementation with key minerals (notably zinc or iron). However, they emphasise that these approaches do not help all children with ADHD, that some of them can be difficult and time-consuming, and that these approaches also require help from professionals in order to ensure proper nutritional balance.
Most significantly, they emphasise the increasing evidence that a modern, western-type diet (rich in highly processed and refined foods) tends to promote ADHD-type symptoms, while a healthier, traditional mediterranean-type diet (low in sugar and refined starches but rich in fibre, vitamns and minerals and omega-3 fatty acids) is associated with lower ADHD symptomatology.
With respect to omega-3, these reviewers did not have the benefit of being able to refer to the recent meta-analysis of studies in this area (Bloch and Qawasmi 2011), showing that omega-3 supplementation does indeed lead to significant reductions in ADHD-type symptoms. Nonetheless, they acknowledge that an increased intake of omega-3 is worth trying whenever parents are open to dietary approaches.
As these authors emphasise, dietary approaches are not a substitute for standard treatments for ADHD, but there is good evidence that these can play an important role - both in addition to standard treatments, and in any cases where these may not be suitable.
For a summary of the main findings from this review, see the related news article: