From evaluation to action: Testing nudging strategies to prevent food waste in school canteens

Food waste (FW) prevention is an essential measure to contribute to the achievement of the Sustainable Development Goal target 12.3, achieve more sustainable food systems and tackle the climate crisis. This paper aims at evaluating nudging strategies' impact on FW prevention in school canteens. To do so, it applies a four-stage methodology in 4 school canteens of the Metropolitan Region of Barcelona as case studies. This study has three main contributions. First, it provided real FW data by estimating a daily FW of 46 g per dinner. Secondly, it observed a 41% FW prevention impact when specific nudging strategies were applied. Dessert was the course with bigger reductions, especially when fruits were served. In addition, strategies involving canteen staff seemed to be more effective. Third, it proposed a methodological framework to co-design and evaluate the impact of FW prevention strategies by quantifying plate waste at school canteens. Thus, this study suggests nudging strategies as innovative interventions to improve food systems' sustainability by preventing FW in school canteens.