To date, few systematic reviews have focused on evaluating the effectiveness of combined diet and physical activity interventions on changes in these targeted behaviours, as opposed to solely examining their impact on obesity related outcomes.

Four electronic databases were searched for controlled intervention studies targeting both diet and physical activity among adolescents aged 10–19 years that reported data on the outcomes of changes in both physical activity and diet.

Interventions were described as demonstrating a positive change (increase), negative change (decrease), or no change on diet and physical activity behaviour. For studies reporting adiposity indicators, a meta-analysis was performed on changes in BMI, BMI z-scores, and body fat percentage.

All 36 interventions included educational components, either as standalone strategies or as part of a multicomponent approach combined with social and/or physical environmental components. While there were some promising outcomes, results were mixed across the different intervention approaches, and a lack of detailed reporting made it difficult to identify the most effective components. 

All studies collected baseline data on gender, but only 17% conducted subgroup analyses to examine gender-specific differences. Even fewer studies collected data on socioeconomic position, religion, or place of residence. Notably, most of the research was conducted in high-income countries, with no evidence from low- or medium-income countries. 

What next?

There is a need to understand what works and why, which could be uncovered from more robust reporting of implementation and process evaluations, as well as standardised measurement and reporting. These results are important in highlighting where gaps in current knowledge exist and can be used to guide future research, policy development, and support practice by identifying what works in improving adolescent diet, activity, and adiposity globally.

Citation details

Pearson N, Pradeilles R, Kingsnorth A, Suarez A, Boxer B, Griffiths P and Sherar, L. The Effectiveness of Combined Dietary and Physical Activity Interventions for Improving Dietary Behaviors, Physical Activity, and Adiposity Outcomes in Adolescents Globally: A Systematic Review and Meta-Analysis. Obesity Reviews (2025). DOI: 10.1111/obr.13940