Evaluating a peer-led nutrition education for improved diet among Ethiopian secondary school adolescents

Arm 1: Peer-Led Nutrition Intervention What is the intervention: A theory-informed, peer-led nutrition education program designed to improve dietary behaviours, nutrition knowledge, and attitudes among secondary school adolescents. The curriculum was grounded in social cognitive theory and covered dietary diversity, macro- and micronutrient functions, healthy food selection, portion control, breakfast consumption, meal skipping, and practical strategies such as planning balanced meals using locally available foods, selecting affordable nutrient-dense alternatives, preparing healthy breakfasts and snacks, interpreting food labels to make healthier food choices, choosing healthier options when shopping or eating outside the home, and reducing the consumption of sugar-sweetened beverages and ultra-processed foods. Ethiopian National Food-Based Dietary Guideline messages were integrated throughout. Environmental components included peer modelling of healthy eating during school breaks, whereby peer educators demonstrated healthy food choices, consumed healthy foods with their peers, and encouraged classmates to adopt healthy eating behaviours through informal discussion and positive role modelling, posters displayed across school compounds, take-home culturally adapted recipe booklets, and student taste-testing of healthy snack alternatives to promote family-level engagement. The flyers, posters, and recipe booklets were specifically designed and culturally adapted for this study based on the Ethiopian National Food-Based Dietary Guidelines and were not existing or commercially available resources. Who delivers it: Twelve peer educators (six per intervention school), selected through a combined student nomination and teacher recommendation process. Selection prioritised peer influence, reliability, willingness to lead, and gender balance across grade levels. Peer educators completed a five-day intensive training delivered by the Principal Investigator, with the cooking demonstration component of the training delivered by a professional chef, covering nutrition concepts, behaviour change communication, and practical skills including food label reading and preparation of affordable nutritious meals. The intervention was delivered by the trained peer educators, while the cooking demonstrations during the intervention were delivered by the professional chef. How it is delivered: Face-to-face, group-based sessions delivered in classrooms, supplemented by cooking demonstrations and reinforcement through flyers, posters, and school mini-media broadcasts. Participatory learning methods included group discussions, scenario-based role plays, and quizzes. How often and for how long: 12 weekly sessions of 60 minutes each, plus 20–30 minute cooking demonstrations, delivered over approximately three months (February to June 2025). Where it is delivered: Secondary school classrooms and school grounds in Addis Ababa, Ethiopia (one public and one private school). Adherence: Session delivery was monitored by the research team, primarily the field supervisor. Reinforcement materials (posters, flyers, mini-media broadcasts) were used throughout the intervention period to sustain engagement. Take-home recipe materials encouraged continued practice outside school hours.