Close Relationships and Health Through the Lens of Selective Investment Theory

This chapter reviews a program of research that was designed to explore the health benefits of helping or giving support to others. This work was inspired by a new evolutionary theory of altruism, selective investment theory (SIT), which recasts the functional significance of social bonds as designed by natural selection to promote adaptive instances of giving. SIT assumes that social bonds enable individuals to suppress self-interest so that they can reliably prioritize and promote the well-being of another, even at a cost to the self. In this way, the social bond resolves the motivational conflict inherent in deciding whether to promote self versus other interests. The chapter describes the results of four studies that demonstrate the health benefits of helping others, including decreased mortality risk, recovery from depressive symptoms following spousal loss, and relief from cardiovascular stress. It concludes with a discussion of promising new directions for future research in this area.