Combining Dynamic Norms and Working Together Appeals to Encourage Sustainable Food Choice in University Cafeterias: A Field Experiment

Livestock production contributes to climate change, environmental degradation, and freshwater scarcity. Excessive consumption of animal-sourced foods (ASF; broadly categorized as meat, fish, eggs, and dairy) in developed countries is also associated with avariety of health and ethical concerns. Shifting ASF-heavy diets to include more plant-sourced foods (PSF; mainly whole grains, legumes, fruits and vegetables, and nuts and seeds) has been identified as an important lever to address these issues. However, food choice is a complex, multifaceted phenomenon influenced by conscious and unconscious processes and deeply embedded in cultural and social practices. Because of its embeddedness in the social context, one approach to changing food choices is to use socialinfluence. Dynamic normative appeals — appeals that aim to make a positive trend salient — have recently been used to guide a variety of pro-environmental behaviors, including food choice. The empirical evidence is hopeful but mixed. Another strand of the literature has suggested that appeals to work together might complement dynamic normative appealsto greater effect. I tested this hypothesis in a field experiment in a university cafeteria, using Instagram posts as a means of message delivery. The results show that while the combined use of dynamic norms and working together appeals did indeed lead to the mostvegan lunch orders, it did not substantially outperform the other conditions. Messaging geared toward sustainability in the food choice context, delivered through Instagram, elicited a generally positive sentiment from the students. I discuss the results from several perspectives, derive recommendations, and conclude with a call for a systemic approach toshifting demand in food choice.