When Social Skills Backfire: Social Media Overuse as a Pathway Linking Social Competence and Health Across Cultures.

This study investigates how self-presentation and social skills relate to physical health among university students in Japan and Hong Kong, with particular attention to the mediating roles of social media use and social support. We conducted two online surveys; as a result, 452 participants in Japan and 289 participants in Hong Kong were analyzed using multi-group structural equation modeling. Across both samples, social skills were directly associated with increased physical symptoms, and this direct association was substantially stronger than the indirect association through social support, which was linked to fewer physical symptoms. Notable cross-cultural differences also emerged. In Japan, self-presentation was directly associated with increased respiratory-sleep symptoms (R-SSs), and this direct association was stronger than the indirect pathway through posting frequency and time spent on social media. In contrast, in Hong Kong, no direct association between self-presentation and physical symptoms was detected, although an indirect association through social media usage time-leading to increased R-SS-emerged at a marginally significant level. These findings highlight the dual and context-dependent effects of personal attributes in digital environments, demonstrating that characteristics typically associated with positive social functioning may produce unintended health consequences online. By integrating personal factors, social media behaviors, and cultural context, this study advances understanding of digital well-being and physical health in contemporary societies.