As more environmental challenges arise, pro-environmental engagement becomes increasingly important. While sustainable diets are widely acknowledged for their ecological benefits, the interplay of...Show moreAs more environmental challenges arise, pro-environmental engagement becomes increasingly important. While sustainable diets are widely acknowledged for their ecological benefits, the interplay of social-emotional factors shaping such choices remained relatively underexplored. This study explored the interplay between guilt proneness, emotional support from best friends, and open- mindedness and their influence on young adults’ pro-environmental dietary choices. These variables were selected for their distinct impacts on decision-making processes and behavioural intentions, as guilt proneness motivates alignment with moral values, emotional support provides social reinforcement and validation, and open-mindedness encourages adoption of atypical diets. Plant-based diets involve (mostly) excluding meat including variations like flexitarian and pescetarian diets, while vegetarian diets exclude meat, and vegan diets exclude meat and animal-derived foods and products. The dietary choices in this study rank from the least to the most sustainable diet, being omnivores, plant-based, vegetarian, and ultimately, vegan. The cross-sectional design incorporated 213 individuals aged 17 to 26 from multiple genders and nationalities. The multiple stages assessment included a 45-minute online survey that employed specific tests to assess the factors. Dietary choice was assessed using the Dietarian Identity Questionnaire, guilt proneness using the Test of Self-Conscious Affect–3, emotional support from best friends using the Official short version of the Network Relationship Inventory, and open-mindedness using the Big Five Inventory-2. The multiple regression analyses indicated that guilt proneness, emotional support from best friend, open-mindedness, and the three-way interaction of these variables were non-significant predictors of dietary choice. These results diverged from initial hypotheses, emphasizing the need for exploration within different contexts and populations. The study's strengths included its cross-sectional design encompassing multiple nationalities and genders, and the thorough validation of statistical assumptions. However, the questionable to low reliability of some measures and the unequal gender distribution possibly affected the generalizability of the findings. Additional factors that may influence dietary choices among young adults, including cultural norms, socioeconomic status, anticipated pride, and peer influence, should be incorporated in future research. Interventions aimed at promoting pro- environmental dietary choices among young adults must adopt a holistic approach, considering individual, social, and environmental factors to facilitate long-term behaviour change.Show less