The Impact of Healthy and Sustainable Food Choices Interventions on Wasted Food: Nutritional and Environmental Aspects of Plate Waste Produced in Italian Hospital Canteens

Healthy and sustainable food consumption implies not only making conscious food choices but also limiting food waste. Interventions targeting choices are effective only if the healthier food selected is not wasted on the plate. The aims of the study were: to quantify plate and service waste in hospital canteens, characterize plate waste (PW), and compare PW before and after an intervention aimed at promoting healthy and sustainable food choices. A descriptive study was conducted in three Italian hospital canteens. Trays of users who gave consent were photographed (N = 1624). PW was quantified visually. Energy, nutrients, and environmental indicators were estimated using portion sizes, recipes provided by the canteens, food composition, and environmental databases. Both plate and service waste varied substantially across canteens. Post-intervention PW was 4.7% (C1: 6.1%, C2: 2.0%, C3: 2.6%) of the served food, corresponding on average to 33.1 g/tray, 43.6 kcal/tray, 69.6 g CO2 eq./tray and 61.8 LH2O/tray. Side dishes contributed most to the total PW. The canteen where PW decreased significantly compared to pre-intervention (C2: −48.9 g/tray in median among wasters) was the one with the least improvement in food choices. These findings highlight the importance of considering waste when implementing food choice interventions.