REVIEW OF: Khoshbakht Y et al, Eur J Nutr 2021;60(7):3647–3658

Dietary approaches for controlling ADHD in children have been studied over many decades, but none have been found to be clearly effective. In a recent study, researchers examined the Dietary Approaches to Stop Hypertension (DASH) diet, which includes several interventions that could be helpful in ADHD: more fruit/vegetable intake, higher essential fatty acids from fish, and foods rich in vitamin C, calcium, and magnesium. The DASH diet also limits the intake of simple sugars, artificial sweeteners, and additives that have been hypothesized to worsen ADHD symptoms.

This randomized controlled trial recruited 80 children with ADHD, ages 6–12, to receive the DASH diet or a control diet for 12 weeks. All but one of the children were boys, and none of the participants had ever used medications or behavioral therapy for ADHD. The control diet was meant to resemble a child’s typical diet and allowed for more refined grains, full-fat dairy products, and simple sugars. All the diets were designed by nutritionists who took into account the child’s individual caloric and nutritional needs. Children and parents were visited monthly over the study period for ADHD assessments and food logs. Researchers measured the severity of ADHD symptoms with various standards scales, including the Abbreviated Conners Scale.

After 12 weeks, the children on the DASH diet improved significantly more than control subjects on most of the scales, including both parent and teacher versions. For example, on the Abbreviated Conners Scale (a 30-point scale), the parent version showed improvements of 4.7 points in the DASH diet group vs 3 points for the intervention group (p = 0.04) while the teacher version showed more impressive improvements—5.3 points for the DASH diet vs 1.9 points for the control (p < 0.001).

A main limitation of this study is that since researchers cannot ethically recommend unhealthy diets for children, the study’s control diet may have been significantly better than what the children were eating before. Moreover, all but one of the children were boys and all the participants were naïve to any medication or behavioral therapy interventions, so the results are difficult to generalize.

CCPR’s Take:
Diet interventions in ADHD have seen less than stellar results, and this study is no exception. Still, the DASH diet includes healthy recommendations regardless of whether they have a significant effect on ADHD, and it may be a good place to start for highly motivated parents who wish to avoid medications. For more information on the DASH diet, see www.dashdiet.org.