Omega-3 fatty acid supplementation for the treatment of children with attention-deficit/hyperactivity disorder symptomatology: systematic review and meta-analysis.

Systematic review and meta-analysis of 10 randomized trials in children with ADHD symptomatology, including diagnosed ADHD and children with ADHD symptoms in other psychiatric or undiagnosed populations. The pooled active intervention arms included 699 participants, generally school-aged children, with both monotherapy and adjunctive use alongside ADHD medication.

Omega-3 fatty acid supplementation was tested in 10 pediatric trials, with formulations varying by EPA content and, in some studies, DHA and/or ALA content. Active regimens ranged from EPA 80 mg to 750 mg daily-equivalent doses, with durations from 7 weeks to 4 months; comparators included placebo oils such as olive, palm, sunflower, canola oil, or vitamin C.

Omega-3 fatty acid supplementation produced a small but statistically significant improvement in ADHD symptoms, but the effect was modest. The primary pooled improvement in ADHD severity was SMD 0.31 (95% CI 0.16 to 0.47, z = 4.04, p < .0001); parent ratings also improved (SMD 0.29, 95% CI 0.14 to 0.44, p = .0002), as did inattention (SMD 0.29, 95% CI 0.07 to 0.50, p = .009) and hyperactivity (SMD 0.23, 95% CI 0.07 to 0.40, p = .005). Higher EPA dose was associated with greater efficacy, whereas DHA and ALA were not significantly associated with benefit; there was no meaningful heterogeneity (I2 = 0%) and no evidence of publication bias.

The overall effect was small and likely clinically modest compared with established ADHD pharmacotherapies. Trials varied in supplement composition, EPA dose, and whether omega-3 was used alone or as augmentation, and active-arm sample sizes were relatively small and treatment durations short. Not all outcomes were available from every trial, and much of the evidence comes from pediatric populations with heterogeneous ADHD definitions and symptom severity.