Randomized open-label trial of docosahexaenoic acid–enriched fish oil and fish meal on cognitive and behavioral functioning in Omani children

•Cognitive and behavioral functioning was assessed in school children before and after intervention with docosahexaenoic acid–enriched fish oil and a fish meal.•Fish oil and a fish meal improved executive functioning with significantly better results with fish oil. Neither verbal ability nor memory was improved.•Fish oil ameliorated attention-deficit/hyperactivity disorder–related symptoms; however, a fish meal did not. This study aimed to examine the effect of docosahexaenoic acid (DHA)–enriched fish oil supplement and meal of grilled fish on cognitive and behavioral functioning manifested as attention-deficit/hyperactivity disorder in primary school students 9 to 10 y of age in Muscat, Oman. This randomized open-label trial involved two types of interventions: fish oil supplement or one serving (100 g) of grilled fish per day (Sunday through Friday) for 12 weeks. Red cell total lipid DHA levels were assessed. The Verbal Fluency Test, Buschke Selective Reminding Test, and Trail Making Test were used to measure cognitive functioning. Behavioral functioning was assessed using a standardized Arabic version of the National Initiative for Children’s Health Quality Vanderbilt Assessment Scales. All measurements were carried out before and after intervention. DHA levels increased by 72% and 64% in the fish oil (mean, 3.6%–6.2%) and fish-meal (mean, 3.4%–5.6%) groups, respectively (P = 0.000). The Trail Making Test was the only cognitive test that demonstrated marked differences between groups: Median interquartile range difference between pre- and postintervention in the Trail Making Part B score was 61.5 (SE, 19.3, 103.2) in the fish oil versus fish-meal group, 24.5 (SE, −15.2, 74.7, P = 0.005). The Vanderbilt Assessment Scales also showed significant differences between groups (P