Primary prevention of overweight and obesity in adolescents: An overview of systematic reviews.

The aim of this overview of systematic reviews was to summarize evidence from up-to-date reviews of the effectiveness of interventions aimed at preventing overweight and obesity in adolescents aged 10 to 19 years. We searched nine databases for systematic reviews published between January 2008 and November 2019. We used A Measurement Tool to Assess Systematic Reviews (AMSTAR) 2 to assess the quality of reviews, excluding those of critically low quality, and the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) tool to grade the certainty of included evidence. We included 13 reviews. Three reviews focused on dietary behaviour, six on physical activity, and four on both types of behaviours. Individual-oriented and school-based interventions dominated. Results across reviews showed little or no effect on body mass index, or physical activity levels of adolescents, whereas results from a couple of reviews suggest possibly beneficial effects of public health interventions on dietary behaviours (i.e., consumption of sugar-sweetened beverages). The certainty of evidence was low to very low for all outcomes. Overall, the evidence base for the effect of primary interventions to prevent overweight and obesity in adolescents is weak. In particular, there is a lack of reviews assessing the impact of environmental interventions targeting adolescents, and reviews addressing social inequality are virtually absent from this body of literature.