Recent scientific work has established both a theoretical basis and strong empirical evidence for a causal impact of social relationships on health. Prospective studies, which control for baseline health status, consistently show increased risk of death among persons with a low quantity, and sometimes low quality, of social relationships. Experimental and quasi-experimental studies of humans and animals also suggest that social isolation is a major risk factor for mortality from widely varying causes. The mechanisms through which social relationships affect health and the factors that promote or inhibit the development and maintenance of social relationships remain to be explored.

https://science.sciencemag.org/content/sci/241/4865/540.full.pdf

Social relationships and health.

Numerous studies show that happy individuals are successful across multiple life domains, including marriage, friendship, income, work performance, and health. The authors suggest a conceptual model to account for these findings, arguing that the happiness-success link exists not only because success makes people happy, but also because positive affect engenders success. Three classes of evidence--crosssectional, longitudinal, and experimental--are documented to test their model. Relevant studies are described and their effect sizes combined meta-analytically. The results reveal that happiness is associated with and precedes numerous successful outcomes, as well as behaviors paralleling success. Furthermore, the evidence suggests that positive affect--the hallmark of well-being--may be the cause of many of the desirable characteristics, resources, and successes correlated with happiness. Limitations, empirical issues, and important future research questions are discussed.

/pdf/the-benefits-of-frequent-positive-affect-does-happiness-lead-4k0h6bmoho.pdf

The Benefits of Frequent Positive Affect: Does Happiness Lead to Success?

Attachment--and loss.

Well-being : the foundations of hedonic psychology

Background 
The quality and quantity of individuals' social relationships has been linked not only to mental health but also to both morbidity and mortality.
Objectives 
This meta-analytic review was conducted to determine the extent to which social relationships influence risk for mortality, which aspects of social relationships are most highly predictive, and which factors may moderate the risk.
Data Extraction 
Data were extracted on several participant characteristics, including cause of mortality, initial health status, and pre-existing health conditions, as well as on study characteristics, including length of follow-up and type of assessment of social relationships.
Results 
Across 148 studies (308,849 participants), the random effects weighted average effect size was OR = 1.50 (95% CI 1.42 to 1.59), indicating a 50% increased likelihood of survival for participants with stronger social relationships. This finding remained consistent across age, sex, initial health status, cause of death, and follow-up period. Significant differences were found across the type of social measurement evaluated (p<0.001); the association was strongest for complex measures of social integration (OR = 1.91; 95% CI 1.63 to 2.23) and lowest for binary indicators of residential status (living alone versus with others) (OR = 1.19; 95% CI 0.99 to 1.44).
Conclusions 
The influence of social relationships on risk for mortality is comparable with well-established risk factors for mortality.

Please see later in the article for the Editors' Summary

/pdf/social-relationships-and-mortality-risk-a-meta-analytic-2ghmxi4ksm.pdf

Social Relationships and Mortality Risk: A Meta-analytic Review

Social relationships—both quantity and quality—affect mental health, health behavior, physical health, and mortality risk. Sociologists have played a central role in establishing the link between social relationships and health outcomes, identifying explanations for this link, and discovering social variation (e.g., by gender and race) at the population level. Studies show that social relationships have short- and long-term effects on health, for better and for worse, and that these effects emerge in childhood and cascade throughout life to foster cumulative advantage or disadvantage in health. This article describes key research themes in the study of social relationships and health, and it highlights policy implications suggested by this research.

/pdf/social-relationships-and-health-a-flashpoint-for-health-5acz10lskr.pdf

Social Relationships and Health: A Flashpoint for Health Policy

This chapter reviews the recent literature on social support and health and its relation to preexisting research and theory in the areas of social networks and social integration. We identify crucial directions for future theoretical and empirical work, focusing on the need to better understand the structures and processes through which social relationships affect human health and well-being. Two elements of social relationship structure are distinguished: (a) social integration, which refers to the existence or quantity of social relationships, and (b) social network structure, referring to the structural properties that characterize a set of relationships. We further identify three social processes through which these structures may have their effects: (i) social support, which pertains to the emotionally or instrumentally sustaining quality of social relationships; (ii) relational demands and conflict, referring to the negative or conflictive aspects of social relationships; and (iii) social regulation...

Structures and Processes of Social Support

Gender, marital status and the social control of health behavior☆

Age-adjusted mortality rates are higher for the unmarried and nonparents than for the married and parents. The effects of marital and parental status on mortality are usually attributed to the positive effects of social integration or social support. The mechanisms by which social support or integration is linked to health outcomes, however, remain largely unexplored. One mechanism may involve health behaviors; the family relationships of marriage and parenting may provide external regulation and facilitate self-regulation of health behaviors which can affect health. The present study employs a national sample to examine the relationships of marital and parenting status to a variety of health behaviors. Results indicate that marriage and presence of children in the home have a deterrent effect on negative health behaviors. It is suggested, within the theoretical framework of social integration, that family roles promote social control of health behaviors which affect subsequent mortality.

Debra Umberson

Papers

Social relationships and health.

Social Relationships and Health: A Flashpoint for Health Policy

Structures and Processes of Social Support

Gender, marital status and the social control of health behavior☆

Family status and health behaviors: social control as a dimension of social integration.