Co-creating a school-based intervention for healthy and sustainable eating among adolescents

Background

Adolescence is a critical period for dietary behaviour development, yet school-based interventions often lack participatory design and robust evaluation. In Portugal, high levels of overweight and low food literacy among adolescents, particularly in disadvantaged settings, highlight the need for structured approaches. The PASCE municipal initiative, designed and implemented by the Institute of Public Health of Porto University and Porto Municipality, aimed to co-create a multicomponent intervention to promote healthy and sustainable eating in schools.

Methods

PASCE was implemented in three public schools in Porto serving socioeconomically disadvantaged populations (May–Dec 2025). Needs assessment included 16 stakeholder interviews and a knowledge, attitudes and practices (KAP) questionnaire applied to 303 students (6th and 9th grades; 81% response rate). Five co-creation sessions were delivered in six classrooms, addressing barriers to healthy eating, food labelling, ultra-processed foods and social marketing. A whole-school activity reached over 1000 participants, and 75 teachers received training. Evaluation included a questionnaire (n = 573; 70.3%), six student focus groups (n = 39), one teacher focus group (n = 3) and a satisfaction survey (n = 114; 95%). Ethical approval was obtained.

Results

KAP data showed limited understanding of healthy eating concepts. Satisfaction was highest for social marketing (76–92%) and barrier identification sessions (75–92%). Over 72% of 6th grade and 83% of 9th grade students reported gaining new knowledge. Focus groups confirmed high acceptability. Practical activities were rated as most effective, while abstract tasks were less engaging.

Conclusions

This pilot demonstrates the feasibility and acceptability of a co-creation approach to improve food literacy among adolescents in vulnerable urban settings. The tools developed provide a basis for scaling school-based interventions.

Key messages

• Co-created school-based interventions are feasible in disadvantaged settings and should be integrated into municipal and national strategies to promote healthy and sustainable diets.

• Policy efforts should prioritise practical, skills-based food literacy approaches, as adolescents gain knowledge but struggle to apply healthy eating concepts in daily choices.