From Plate to Planet: A Systematic Review and Meta-Analysis on Strategies to Reduce Plate Food Waste at Food Services

Annually, over 931 million tons of plate food waste is generated in food services, affecting various aspects of sustainability. Therefore, this review aims to evaluate the most effective strategies or actions to reduce plate food waste. A systematic review and meta-analysis were conducted following a PROSPERO-registered protocol [#CRD42024501971], searching multiple databases and gray literature until August 2024. Studies evaluating strategies and actions against waste in various food services [restaurants, institutional services in hospitals, childcare centers, schools, universities, or businesses] were included, with no language, location, or date restrictions. The risk of bias was assessed using JBI tools. A random-effects meta-analysis was performed in R (version 4.2.1), with subgroup analyses based on intervention type, food service type, meal type, management, and distribution systems. Of the 6070 studies, 18 were included in the narrative synthesis and 6 in the meta-analysis. The most effective strategies or actions targeted clients (vs. employees), meals on plates (vs. trays), school canteens (vs. other services), self-managed establishments (vs. outsourced), and & agrave; la carte services (vs. self-service). In this sense, strategies focusing on clients, plate-served meals, school canteens, self-management, and & agrave; la carte services are more effective in reducing food waste. Further actions are needed in other areas like customers, trays, different kitchen types, outsourced services, and self-service menus.