Reduced loneliness mediates the effects of multiple group identifications on well-being.

Membership of multiple groups and identification with those groups have been found to be positively related to individuals' health and well-being. The present research sought to replicate this finding in two large, representative samples. Moreover, we sought to extend previous work by shedding light on the mechanisms mediating the effects of multiple group membership on positive health outcomes. Specifically, we proposed that the links between multiple group membership and positive health outcomes are mediated by reduced feelings of loneliness. In Study 1, a two-wave survey of a German population, participants (N = 989) were asked about their identification with family, friends, neighbourhood, their country and humanity and 4 weeks later about feelings of loneliness, physical health and stress. As hypothesized, multiple identifications predicted lower stress. They were also associated with a marginal reduction in physical symptoms of poor health. Both relationships were mediated by the absence of loneliness. In Study 2, we conducted a cross-sectional survey of German participants (N = 1635), which also included a sixth target of identification (Europe). Results replicated findings from Study 1 and also found similar relations associated with smaller (family, friends and neighbourhood) versus larger (country, Europe and Humanity) foci of identification.