The role of green nudges in triggering psychological reactance and influencing vegetarian food choice: a moderated–mediation approach

This paper investigates the psychological mechanisms underlying the (in)effectiveness of green nudges promoting vegetarian choices. While prior research has primarily assessed whether nudges work, the present study focuses on how they operate. Drawing on Construal Level Theory (CLT) and Psychological Reactance, we examine whether nudges trigger psychological reactance, whether reactance mediates their impact on food choice, and whether socio-demographic variables such as gender play a moderating role in this process. In a laboratory experiment (N = 150), students chose between a vegetarian and a meat-based dish under five conditions: a control group, two How-based nudges designed to enhance feasibility (Visibility, Accessibility), and two Why-based nudges designed to enhance desirability (Social Desirability, Emotional Activation). Nudges did not directly increase vegetarian choices. However, all nudges heightened psychological reactance, which significantly reduced the likelihood of selecting the vegetarian option. Importantly, moderated mediation analyses revealed that the indirect effect of Why-based nudges via reactance was significant for men but not for women. These findings advance nudge research by shifting attention from effectiveness to mechanisms, integrating CLT and Psychological Reactance Theory, and highlighting gender as a boundary condition.