Food waste salience and task knowledge to reduce individual food waste: A field experiment in a restaurant setting

Food waste related to individual consumption creates high economic, social and environmental costs. This study explores two informational strategies for reducing food waste among restaurant guests. We test a two-stage intervention to achieve a customer food waste reduction. First, we introduce a food waste-related message emphasizing the salience of food waste as an issue and highlighting the restaurant’s commitment to reducing food waste, inviting guests to join its efforts before they select their meals. The second intervention additionally informs guests with details about the portion size of each meal and encourages reflection on their current hunger levels. We find that salience about the issue of food waste alone leads to a 16 percentage point reduction in the probability of reporting food waste compared to the control group. The second intervention, which provides additional task knowledge on better matching individual hunger with ordered portion size, shows no difference from the control. We further explore pathways on how salience reduces the probability of reporting food waste and show that the effective intervention had no negative effects on customer satisfaction. • Highlighting the issue of waste before ordering food reduces leftovers in restaurants. • No evidence that providing portion size information affects plate waste. • Behavioural interventions reduce food waste without affecting customer satisfaction.