A systematic review of school meal nudge interventions to improve youth food behaviors.

BACKGROUND: School meal programs have a large reach and thus are ideal environments in which to implement interventions targeting improved youth eating behaviors and reduced food waste. This systematic review summarizes the evidence on the effectiveness of school meal nudge interventions on influencing children's eating and waste behaviors. METHODS: Inclusion criteria required studies have participants in primary or secondary school (grades K-12) with interventions that occurred during school lunch or breakfast in the cafeteria and included at least one of the following outcomes: selection, consumption, waste, or school meal participation. Analyses of intervention outcomes were restricted to studies of strong and moderate quality. RESULTS: Twenty-nine studies were included in the quality assessment. Included interventions fell into three categories: 1) placement/convenience, 2) marketing/promotion, or 3) variety/portions. The 20 strong and moderate quality studies included in outcome analyses generally used strong data collection methods and study designs, but were limited by an overall lack of intervention fidelity checks. Multi-component interventions often did not use methods that allowed for separate analyses of outcomes for different intervention components. CONCLUSIONS: School meal nudge interventions were positively associated with food selection, and had an inconsistent relationship with food consumption. There were few studies evaluating the impact of nudge interventions on meal participation or food waste. The limited evidence available links nudges to improved meal participation, as well as undesirable increases in food waste. Future research in this area should use methods that incorporate implementation metrics, attend to systems factors, and allow the outcomes of individual intervention components to be isolated.

Implementation of a Multi-Component School Lunch Environmental Change Intervention to Improve Child Fruit and Vegetable Intake: A Mixed-Methods Study.

Nudge interventions are widely used to promote health in schools, yet implementation metrics are seldom used to understand intervention outcomes. A multi-component intervention consisting of cafeteria decorations, creative names, social norming taste tests, and flavor station components was implemented in three rural elementary school cafeterias by school nutrition services (SNS) and extension staff. Selection and consumption of fruits and vegetables at lunch were measured through monthly plate waste assessments over eight months (n = 1255 trays). Interviews were conducted with SNS staff (n = 3) upon completion of the intervention to assess implementation outcomes using validated acceptability and feasibility metrics. Consumption findings were generally inconsistent across schools and time points, yet fruit consumption increased at School 1 (p < 0.05) during the taste test and flavor station intervention months and School 2 (p < 0.001) during the creative names intervention months compared to baseline. Odds of selecting a vegetable at School 3 were three times higher than baseline during the taste test intervention months (odds ratio (OR), 3.0; 95% confidence interval (CI), 1.3-6.5). Cafeteria decorations and taste tests had higher reported implementation metrics for acceptability and feasibility than other interventions. Thematic analysis underscored the facilitating role of extension support, as well as systems factors, which served as facilitators and barriers across schools and interventions. These findings suggest that nudge interventions are a promising strategy to improve vegetable selection and fruit consumption in school meal programs.