The impact of intergenerational rearing on food waste: The mediating role of self-control

Food waste behavior is shaped by multiple factors, yet the role of family structure—particularly intergenerational rearing—has been largely overlooked. Intergenerational rearing, where grandparents take on primary (though not exclusive) caregiving responsibilities during childhood, is increasingly common and culturally relevant in many societies. This research examines whether intergenerational rearing influences food waste behavior and explores self-control as a potential psychological mechanism. Through four experiments, we compared participants with and without intergenerational rearing experience using both subjective (self-reported) and objective (behavioral) measures of food waste. Experiment 1 examined the relationship between self-control and self-reported food waste using a questionnaire employing a Likert-scale format. Experiment 2 replicated the findings with a larger sample. Experiment 3 introduced a real-world behavioral measure of food waste, in which uneaten food (oatmeal) was weighed after a naturalistic eating task. Experiment 4 controlled for household economic status and used diverse self-control measures to verify the robustness of the results, employing the same self-reported measure of food waste (a Likert-scale questionnaire) as in Experiments 1 and 2. Across all experiments, individuals who experienced intergenerational rearing during childhood demonstrated significantly lower self-control, which was associated with greater food waste—both in self-reports and objectively measured outcomes. These findings reveal a possible psychological pathway linking early caregiving environments to food-related behaviors. The study offers theoretical insight into how family structure shapes consumption outcomes and provides practical implications for parenting interventions and targeted food waste reduction strategies.