Marriage and health are closely related. Married people experience lower morbidity and mortality across such diverse health threats as cancer, heart attacks, and surgery. There are gender differences in these effects which may be partially due to men's and women's relative status. Most research on marriage and health has focused on heterosexual couples, and more work is needed to clarify the health effects on same-sex marriage. Simply being married, as well as the quality of one's marriage, has been linked to diverse measures of health. Research has examined the social-cognitive, emotional, behavioral and biological processes involved in these links.
Compared to other relationships
Beyond marriage, social relationships more broadly have a powerful impact on health. A meta-analysis of 148 studies found that those with stronger social relationships had a 50% lower risk of all-cause mortality. Conversely, loneliness is associated with increased risk for cardiovascular disease, and all-cause mortality. Little work has directly compared the health impacts of marriage compared to those of non-romantic relationships, such as connections with friends or colleagues. However, there are several reasons why marriage may exert a greater health impact than other relationships, even other cohabiting relationships: married couples spend time together during a wide variety of activities, such as eating, leisure, housekeeping, child-care and sleep. Spouses also share resources and investments such as joint finances or home-ownership. Relative to other relationships, the increased interdependence of marriage serves as a source for more intense support.
Romantic couples who live together, but are unmarried, may represent a middle ground in health benefits between those who are married, and those who self-identify as single. However, people live together without getting married for many different reasons; cohabitation may serve as a prelude to marriage. Selection factors of race, ethnicity, and social-economic status predispose certain groups to cohabit unmarried, and these factors also affect the health benefits of marriage and cohabitation.
Same-sex marriage
Most research on marriage and health has studied heterosexual couples. Same-sex and opposite-sex couples share many similarities. Both begin marriage with high levels of relationship satisfaction, followed by later declines, and both argue with similar frequency about similar issues.
However, same-sex couples resolve conflicts more effectively, and distribute household labor more fairly compared to their heterosexual counterparts. Same-sex marriage is or was illegal in many countries, including many parts of the United States (where much research on marriage and health has been conducted) until 2015. In these regions same-sex couples are not granted the institutional protections of marriage or its accompanying legal barriers to relationship dissolution. Moreover, same-sex couples are more likely to experience discrimination against their sexual orientation, contributing to problems with mental health and relationship quality.
Gender differences
The health-protective effect of marriage is stronger for men than women. Marital status — the simple fact of being married — confers more health benefits to men than women. Women's health is more strongly impacted than men's by marital conflict or satisfaction, such that unhappily married women do not enjoy better health relative to their single counterparts. Laboratory studies indicate that women have stronger physiological reactions than men in response to marital conflict.
These gender differences may be partially due to men's and women's relative status in a relationship. Research in humans and animals suggests subordinate status is linked to greater physiological reactions to social stress. Indeed, subordinate spouses show greater physiological reactions to arguments with their partner. Both husbands and wives show stronger physiological reactions to arguments when making demands for change from their partner. Women's heightened physiological reactions to marital conflict may be due to their relative subordinate position in marriage.
Measuring health
Research on the links between marriage and health has measured diverse outcomes. These are broadly categorized as clinical endpoints, surrogate endpoints, and biological mediators. Clinical endpoints are variables which affect how people feel, function, and survive. They are recognized as important outcomes by health care providers and patients, for instance being hospitalized, or having a heart-attack.