LAUSR

OBJECTIVES This study examined whether social network size and allostatic load (AL) mediated the association between multiple group membership (MGM) and future physical and psychological well-being. METHODS A longitudinal design was used and data from 1026 healthy participants on the relevant variables was extracted from Wave 2(2010-12), Wave 3 (2011-2013) (for baseline MGM, social network size and AL) and Wave 9 (2017-19) (for well-being at follow-up) of the Understanding Society UK population-based dataset. RESULTS MGM was not directly associated with future well-being, but both social network size, β = 0.06, t = 2.02, p = .04, and AL, β = -0.06, t = -2.05, p = .04, were associated with physical but not psychological well-being at follow-up. Those who had higher numbers of friends had better physical well-being, and those who had lower AL risk scores had better physical well-being at follow-up. However, MGM was indirectly associated with physical well-being through social network size, and AL such that those reporting higher MGM, reported a greater number of friends which was associated with a lower AL and then future physical well-being, β = 0.004, CI [0.001., 0.0129]. This was not evident for psychological well-being. This mediation withstood adjustment for confounding factors (e.g. age, gender, marital status lifestyle factors). CONCLUSION The present study extends findings on the existing social relationships and social cure literature and our findings are discussed in relation to the social cure hypothesis.