ABSTRACT
Despite efforts to curb the rise in Mexico's child and adolescent overweight and obesity rates, prevalence in Mexico has grown by 120% since 1990 to 43.3% in 2022. This investment case identifies policies that will produce the largest returns for Mexico. The investment case model builds beyond a cost-of-illness analysis by predicting the health and societal economic impact of implementing child and adolescent overweight and obesity interventions in a cohort aged 0-19 from 2025 to 2090. The Markov model's impacts include healthcare expenditures, years of life lost, and reduced wages and productivity. We projected and compared costs in a status quo scenario to an intervention scenario to estimate cost savings and calculate return-on-investment (ROI). Total lifetime health and economic costs amount to USD 1.8 trillion-USD 30 billion on average per year. Implementing five interventions can reduce lifetime costs by approximately 7%. Each intervention has a low cost per disability-adjusted life year averted over 30-year, 50-year, and lifetime horizons. The findings demonstrate that a package of interventions mitigating child and adolescent overweight and obesity offers a strong ROI. The novel investment case methods should be applied to other countries, particularly low- and middle-income countries.