Umbrella Review of School-Based Nutrition Policy, Systems, and Environmental Strategies to Improve Nutrition and Reduce the Risk of Obesity Among School-Aged Children in the United States

Background/Objectives: School-based nutrition policy, systems, and environmental (PSE) strategies have the potential to improve children’s nutrition and reduce the risk of obesity. This umbrella review synthesized evidence from systematic reviews examining school-based PSE strategies and their associations with nutrition- and weight-related outcomes among school-aged children in the United States. Methods: PubMed was searched for systematic reviews and meta-analyses (2010–2026). Screening and extraction were conducted in duplicate. Methodological quality was assessed using an adapted AMSTAR 2. The review was registered (PROSPERO-2026 CRD420261387630). Results: Eighteen systematic reviews were included. PSE strategies examined included: breakfast after the bell (BATB), school nutrition policies, local food initiatives, cafeteria environment changes, and universal free school meals (UFSM). Consistent evidence supported positive associations with meal participation for BATB, food environment policies, and UFSM. Evidence also suggested improvements in school meal consumption and/or diet quality with BATB, food environment policies, local food initiatives, and some cafeteria environment changes. Few studies examined food security or weight-related outcomes. Research among subpopulations was generally limited, with the strongest evidence for BATB and food environment policies improving meal participation and nutrition outcomes among students from lower-income households. Four out of the eighteen reviews were of high or moderate quality based on the adapted AMSTAR rating. Conclusions: Multiple school-based nutrition PSE strategies were associated with positive associations regarding school meal participation and consumption, but more research is needed to examine food security or weight-based outcomes. Future research should prioritize strong study designs and objective measures, as well as evaluate impacts on subpopulations at greatest risk for adverse health outcomes. Finally, multicomponent PSE strategies with sufficient dose and duration should be implemented to maximize effectiveness.