Dietitian-led school-based nutrition education and its effects on knowledge, attitudes, behaviours and anthropometric measurements: a randomized controlled trial

BACKGROUND: This study aimed to evaluate the effects of a dietitian-led, school-based nutrition education programme on primary school students’ nutrition knowledge, attitudes, behaviours, and anthropometric measurements. METHODS: A randomized controlled, prospective design was conducted in a primary school in Mardin with 67 fourth-grade students (32 intervention, 35 control). The intervention group received 8 weeks of classroom-based nutrition education, and their parents received 4 weeks of education. Data were collected via sociodemographic forms, anthropometric measurements, Nutrition Knowledge Test (NKT), Nutrition Attitude Scale (NAS), Nutrition Behaviour Scale (NBS), and Child Physical Activity Questionnaire (CPAQ). RESULTS: The intervention group showed significant improvements in knowledge, attitudes, and behaviours (p < .001). A significant reduction in waist circumference was observed (p = .023). Physical activity was negatively correlated with waist circumference and positively correlated with nutrition behaviour scores. ANCOVA results confirmed significant group effects favouring the intervention group in NKT and NAS post-test scores after adjusting for baseline differences (p = 0.007 and p < 0.001, respectively). CONCLUSIONS: School-based nutrition education programs conducted by dietitians can improve children’s nutrition knowledge, attitudes, and behaviors and support healthier anthropometric outcomes such as waist circumference. These findings support the inclusion of nutrition education provided by dietitians to promote the development of healthy eating habits in children in national health and education strategies. TRIAL REGISTRATION: The trial is registered at ClinicalTrials.gov (CT.gov identifier: NCT07168928, Registered 11 September 2025).