Past literature on mental health has extensively discussed the effect of interpersonal relationships on mental health, but studies have yet to systematically investigate the meaning and influence of group membership. This study thereby focuses on the influence of group membership that individuals form through private groups on mental health. We particularly explore the possibility that the positive influence of the number of memberships on mental conditions turns negative when individuals suffer from excessive obligations and requirements from the groups they engage. Using data from the 2023 Korea Social Integration Survey, results from ordered logistic regression analyses suggest that the relationship between group membership and mental distress shows a U-shape. While one’s membership in private groups is negatively associated with anxiety, depressive symptoms, and suicidal thoughts even after controlling for interpersonal contact network as well as other socio-demographic characteristics, the association becomes positive when one engages in an excessive number of groups. Furthermore, we find this U-shape relationship to be significant only in urban communities, not smaller local communities. Our study provides implications for understanding how and under which social conditions membership in social groups shape one’s mental health.
Hong et al. (2026) studied this question.