School Nutrition Standards and Childhood Obesity Prevention: Assessing Policy Compliance and Long-term Health Effects in Low-Income Communities in Pakistan

Background: Childhood obesity is an escalating crisis in Pakistan, exacerbated in low-income communities by obesogenic food environments. The national School Health and Nutrition (SHN) Strategy aims to create healthier school food spaces, but its real world effectiveness remains unassessed. This study investigated the relationship between compliance with the SHN Strategy and long-term changes in children's weight status in low-income schools in Karachi. Methods: A three-year (2020-2022) longitudinal cohort study was conducted across 12 schools. Policy compliance was assessed using a validated tool, categorizing schools as High, Moderate, or Low Compliance. Anthropometric measurements (BMI z-scores) of 528 children were tracked annually. Mixed-methods included quantitative surveys and qualitative interviews with stakeholders. Results: Only 16.7% of schools maintained High Compliance. A significant interaction was found between time and compliance group on BMI z-scores (p<0.01). Children in High Compliance schools showed a slight decrease in mean BMI z-score (-0.07), while those in Moderate and Low Compliance schools showed increases (+0.11 and +0.19, respectively). The prevalence of overweight/obesity remained stable in High Compliance schools (18.2% to 17.0%) but increased significantly in Moderate (21.4% to 26.4%) and Low Compliance schools (20.5% to 29.1%). Key barriers to compliance were financial pressures, student preferences, and lack of enforcement. Conclusion: Faithful implementation of school nutrition standards is effective in mitigating unhealthy weight gain in children. Moving from voluntary guidelines to mandatory, monitored regulations with economic incentives is crucial for public health impact. DOI: https://doi.org/10.59564/amrj/03.04/005