Sociodemographic and behavioural determinants of vegetarian main dish selection in a French university cafeteria: A three-month observational study with repeated measures.

Reducing meat consumption is crucial for improving population and planetary health. Millions of students regularly eat at university cafeterias, which offer a unique opportunity to promote meat-free meals to new generations by addressing barriers such as accessibility, price, and cooking skills. This study aimed to analyse the individual characteristics associated with the proportion of vegetarian main dish choices in a university cafeteria and to determine whether this behaviour influenced the nutritional quality and environmental impact of student meals. A sample of 257 French students who ate regularly at a large university cafeteria took part in an observational study with repeated measures. They took pictures of their meal trays each time they ate at the cafeteria for three months. They completed an online questionnaire to assess their sociodemographic characteristics and various behavioural determinants of the choice of a vegetarian main dish based on the Capability, Opportunity, Motivation Behaviour (COM-B) framework. Being a woman was the only sociodemographic characteristic significantly associated with more frequent vegetarian main dish selection. The proportion of vegetarian choices was negatively associated with attachment to meat (p < 0.001, η = 0.189) and positively associated with environmental knowledge (p = 0.034, η = 0.018) and the following food choice motives: animal welfare (p < 0.001, η = 0.062), health (p < 0.001, η = 0.044), ethics (p = 0.002, η = 0.039), natural content (p = 0.010, η = 0.026), religion (p = 0.014, η = 0.025), and mood (p = 0.022, η = 0.020). Students who chose vegetarian main dishes more frequently composed healthier (p = 0.023, η = 0.020) and more environmentally friendly meal trays (p < 0.001, η = 0.349). These findings highlight the variability in the students' propensity to choose vegetarian main dishes in a university cafeteria and its association with motivational factors in a food environment bound by design.