A meta-analytical review of intervention experiments to reduce food waste

To reduce food waste, many behavioural intervention experiments have been conducted worldwide, but their effectiveness remains unclear. To assess their impacts, we present a meta-analysis based on 58 studies, selected after screening 1143 papers, which were conducted between 2011 and 2021 covering 26 533 participants. We confirm that behavioural interventions have a moderate effect (z = 0.22) on food waste reduction, with education programs having the most significant impact and informational feedback having the least. We also show that interventions in elementary and middle school settings marginally improve the overall effect size (P < 0.1), and controlled experiments exhibit a higher effect size compared to pre-post experiments in education interventions (P < 0.05). Finally, we present a roadmap to guide future research in the next decade to further improve our understanding on the effects of behavioural interventions to reduce food waste.