Mindfulness, Emotion Regulation, and Psychological Distress: A Cluster Randomized Controlled Trial with High-Achieving University Students in China

Abstract Objectives First-year college students navigating the transition into emerging adulthood face heightened psychological vulnerability, particularly within competitive academic environments. This study examined whether a mindfulness-based intervention can enhance mindfulness and reduce psychological distress, and whether these effects operate through emotion regulation strategies, including cognitive reappraisal and expressive suppression. Method A cluster randomized controlled trial (cRCT) was conducted with 218 first-year students from a Double First-Class university in China. Participants in the intervention group completed an eight-session mindfulness-based program. Pretest and posttest data were analyzed using structural equation modeling within a residualized change framework, controlling for baseline measures and demographic covariates. Results The intervention significantly increased mindfulness over time relative to the control group. Posttest mindfulness was positively associated with cognitive reappraisal ( β = 0.39, p < 0.001) and negatively associated with expressive suppression ( β = − 0.26, p < 0.001). Cognitive reappraisal predicted lower psychological distress ( β = − 0.22, p < 0.001), whereas suppression predicted higher distress ( β = 0.17, p = 0.012). Mindfulness also had a direct negative effect on distress ( β = − 0.22, p < 0.001). Indirect effects through emotion regulation were significant ( β = − 0.13, p < 0.001), accounting for 36.86% of the total effect. Conclusions Mindfulness reduces psychological distress through both direct and emotion regulation pathways. By focusing on first-year students in a hypercompetitive academic setting, this study demonstrates that early, mechanism-based mindfulness interventions can support adaptation and resilience during the transition into emerging adulthood. Preregistration This study is not preregistered.