Trends in the prevalence of overweight and obesity in children and adolescents in France in the 21st century: a systematic review and meta-analysis

BackgroundWe aimed to systematically assess temporal trends in paediatric overweight and obesity prevalence in France over the past 2 decades, given the lack of regular nationwide monitoring. MethodsWe systematically searched for both published and unpublished studies reporting the prevalence of overweight (including obesity) and obesity, defined by BMI and IOTF thresholds, from January 2000 to December 2024 in the paediatric population (aged 2-17 years) living in France. Risk of bias was assessed with a customised version of Hoys score for prevalence studies. We selected nationwide studies with a low risk of bias, stratified by sex, to estimate summary prevalence using meta-analyses and to assess temporal trends using meta-regressions adjusted for age, using inverse-variance-weighted, multilevel, linear, random-effects models. We conducted sensitivity analyses including all studies regardless of risk of bias. FindingsOf 2,421 publications screened, 188 were included and 122 were unique studies; 18 studies (n=143,655 children) were nationwide with low risk of bias. No nationwide study at low risk of bias was available after 2017. Summary prevalence of overweight (including obesity) was 18.2% (95% CI 16.5-20.0) for girls and 16.0% (14.2-17.9) for boys. We found no statistically significant temporal trend for overweight and obesity from 2000 to 2017 for either sex. The sensitivity analyses revealed significant positive temporal trends for overweight and obesity, except for overweight in boys. InterpretationWe found no significant increase in the prevalence of overweight and obesity among children and adolescents living in France from 2000 to 2017. However, including studies regardless of risk of bias led to different conclusions. Repeated, high-quality nationwide studies are urgently needed in France to reliably monitor trends in paediatric overweight and obesity prevalence and to assess the effectiveness of public health policy. FundingDoctoral School 393 Pierre Louis of Public Health (CLG).