Social Connection

Research summary

• A widely cited meta-analytic review of over 300,000 participants found stronger social relationships are associated with a 50% reduction in mortality risk, comparable in magnitude to established risk factors like smoking.
• This is reinforced by more specific literatures: meta-analyses link both marital quality and marital status to better health and lower mortality in older adults, while a separate meta-analysis found widowhood is associated with increased mortality risk, together suggesting the presence and quality of close relationships both matter independently.
• Volunteering — a form of social and civic engagement — is associated with lower mortality risk in older adults in meta-analysis, and social support and integration are linked to lower levels of inflammatory cytokines, a plausible biological pathway.
• Nearly all of this evidence is observational, so the precise causal contribution of relationships themselves (versus confounding health and socioeconomic factors) is not fully isolated, but the consistency across relationship types and outcomes is notable.