Social cohesion is defined as the sense of belonging, solidarity and shared values within a group. Although the terms "social capital" and "social cohesion" are sometimes used interchangeably, strictly speaking the former refers to the resources embedded in social relations - such as trust and norms of cooperation - which then create social cohesion. Social cohesion has been studied as a predictor of mental health in residential communities, schools and workplaces. Taking a life-course perspective, this paper reviews the empirical evidence linking social cohesion to common mental disorders, psychosis, suicidality and substance misuse. Consistent evidence is found for a protective association between social cohesion and common mental disorders, suicidality and substance misuse. Findings are mixed for psychosis. Hypothetical pathways explaining the link between social cohesion and mental health include that: a) living in a cohesive community promotes neighborly interactions which may reduce residents' risk of becoming socially isolated; b) social cohesion buffers the deleterious effects of adversity; and c) social cohesion lowers crime and increases safety perceptions. Important gaps remain in the literature, including the need for improved measurement (greater consistency in the use of indicators to measure social cohesion, developing measures to capture bridging social capital, and enhancing the validity of multi-item instruments via application of item-response theory); the need to strengthen causal inference; and the need for participatory intervention studies that demonstrate how social cohesion can be intentionally generated, and for whom it can be beneficial. Investing in the strengthening of social cohesion represents an asset-based approach to mental health promotion. In contrast to a deficits-based approach (such as efforts targeting loneliness or social isolation), increased attention to social cohesion can be viewed as targeting an upstream driver of both social isolation and loneliness, as well as an independent determinant of population mental health.
Ichiro Kawachi (Fri,) studied this question.