This study followed 3680 children in Rotterdam, the Netherlands, from the Generation R Study. It was a general population group, not children diagnosed with ADHD. Parents rated their child's ADHD symptoms at about age 6 and again near age 10. At about age 8, parents reported what the child ate.
Children with more ADHD symptoms at age 6 went on to have slightly lower diet quality at age 8. The link was small (0.08 of a standard deviation lower diet score per 1-point higher symptom score). The reverse did not hold. Diet quality at age 8 did not predict ADHD symptoms at age 10 once other factors were accounted for. A simpler analysis had shown a small link (0.06 of a standard deviation), but it did not survive full adjustment. Results were similar for boys and girls and after leaving out children on ADHD medication.
Parents reported both diet and symptoms, which can bring recall errors. Changes over time were not taken into account, and the children's young age may have hidden a diet effect. Children with missing diet data more often came from lower-income families. The authors call for repeat studies.
The authors suggest that, if the results are replicated, health care professionals working with children with ADHD could monitor their diets and offer parents healthy food suggestions, though the study does not show diet reducing ADHD symptoms.
Source: Mian A, Jansen P, Nguyen A, et al.. Children's Attention-Deficit/Hyperactivity Disorder Symptoms Predict Lower Diet Quality but Not Vice Versa: Results from Bidirectional Analyses in a Population-Based Cohort. The Journal of Nutrition (2019). doi:10.1093/jn/nxy273