The Effects of Interventions Using Support Tools to Reduce Household Food Waste: A Study Using a Cloud-Based Automatic Weighing System

Food waste is a global sustainability issue, and in Japan, approximately half of all food waste is generated in households. This study focused on refrigerator management behaviors aimed at using up the food inventory in the home. An intervention study involving 119 households with two or more members across Japan, with a two-week baseline period and a two-week intervention, was conducted. Target behaviors were set as “search food that should be eaten quickly,” “move it to a visible place,” and “use the foods that should be eaten quickly,” and tools to support these behaviors were selected, including an organizer for the refrigerator, photos, and food management apps. Each tool was assigned to approximately 30 households, and a control group was established. Food waste was measured using a cloud-based automatic weighing system, and all participants were asked to separate avoidable food waste at home and dispose of it in the designated waste bin. During the intervention period, the average weekly food waste per household decreased by 29% to 51% in the intervention group, while there was little change in the control group. An analysis using a two-way mixed ANOVA revealed a marginally significant interaction (p < 0.10), indicating moderate effectiveness. Among the behaviors contributing to reduced food waste, three actions—“having trouble not being able to recall food inventory at home during shopping,” “moving foods that should be used sooner,” and “organizing refrigerator”—showed significant interaction effects (p < 0.05) in a two-way mixed ANOVA, indicating the effectiveness of the intervention.