structural:summarization, information:classification
Physical health

High quality intimate relationships have a positive impact on physical health, and associations between close relationships and health outcomes involving the cardiovascular, immune, and endocrine systems have been consistently identified in the scientific literature. Better relationship quality is associated lower risk of mortality and relationship quality impacts inflammatory responses such as cytokine expression and intracellular signaling. Furthermore, intimate partners are an important source of social support for encouraging healthy behaviors such as increasing physical activity and quitting smoking. Sexual activity and other forms of physical intimacy also contribute positively to physical health, while conflict between intimate partners negatively impacts the immune and endocrine systems and can increase blood pressure.

Laboratory experiments show evidence for the association between support from intimate partners and physical health. In a study assessing recovery from wounds and inflammation, individuals in relationships high in conflict and hostility recovered from wounds more slowly than people in low-hostility relationships. The presence or imagined presence of an intimate partner can even impact perceived pain. In fMRI studies, participants who view an image of their intimate partner report less pain in response to a stimulus compared to participants who view the photo of a stranger. In another laboratory study, women who received a text message from their partner showed reduced cardiovascular response to the Trier Social Stress Test, a stress-inducing paradigm.