How this one life decision can affect longevity

Tying the knot is likely one of the biggest decisions a person will ever make. According to the CDC, there are 2 million marriages in the United States every year, with 6.1 marriages per 1,000 people. And, although an unpleasant topic, there are 746,971 reported divorces.

With all this marrying (and divorcing) going on, it’s intriguing to wonder what effect matrimony exerts on health. Indeed, research shows there are tangible health benefits to being in love, such as lower blood pressure, reduced anxiety, improved immunity, less pain, and longer life. But in the aggregate, the impact of marriage on health represents a mixed bag, complicated by a number of factors. 

In a bid to better understand the relationship between marriage and health (pun intended), here’s a look at the research. 

Studies supporting marriage

Authors of a study published in Psychoneuroendocrinology assert that married people are usually healthier than those who are unmarried. Compared with those who are married, people who are divorced, separated, never married, or widowed exhibit higher rates of morbidity and mortality. Those who were previously married experience more social isolation, a loss of social support, and stigma secondary to separation. Moreover, married people may experience better access to health insurance, enjoy a wider social network, and benefit from additional regular routines, which all promote health.

In the study, the authors examined the associations between salivary cortisol levels—which served as a proxy for stress—and marriage in a sample of 572 adults aged 21 to 55 years. They found that married people exhibited lower cortisol levels vs never-married or previously married men and women. 

“Differences in cortisol levels were due at least in part to currently married individuals having a more rapid decline in cortisol through the afternoon hours compared to individuals who were never married (but not those who were previously married),” the authors wrote.“

Furthermore, there was an interaction between perceived stress and marital status in predicting cortisol levels. Specifically, higher stress was associated with higher cortisol levels for previously married individuals but not for the married or never married. The results of this study support cortisol as one candidate mechanism accounting for the association of marital status and health.”

One important caveat that tempers any findings linking marriage to better health has to do with the quality of marriage. In a study published in the Journal of Happiness Studies, the authors note that unhappy marriages affect health outcomes. “[O]ur results suggest that individuals in unhappy marriages may be a vulnerable population. We conclude that subjective well-being and relationship quality contribute to the health benefits of marriage,” the authors wrote.

The flip side

As previously mentioned, not all researchers have discovered a reliable link between health and marriage. 

According to the results of a study published in the Journal of Marriage and Family, the authors found that married adults were only slightly happier than unmarried adults, and that married people do not usually garner greater health benefits than unmarried people. One exception could be improved mental health in men who are continuously married.

The researchers noted that confounding variables influence the results of studies examining the link between marriage and health.

“[C]omparing the associations between marriage and health status across only one component of the likelihood of marriage may lead to describing differences in the benefits of marriage that are largely due to other characteristics,” they wrote. “Therefore, without accounting for a broad range of premarriage selection factors, we may incorrectly estimate the overall marriage effect on health and any heterogeneity in this marriage effect.”  

Results from a Swedish study also indicated that the physical and mental health benefits of marriage are likely overstated. Moreover, health measures in divorced people often rebound considerably in the years after divorce.

The authors noted that “results are highly sensitive to the outcome studied. Effects are strongest for life satisfaction, weak for mental health, and almost absent for two concrete health measures. We speculate that marriage is primarily linked to a more positive evaluation of one’s life rather than to better health.”

Bottom line

Studies linking health and marriage are rife with confounding variables and often misgauge primary outcomes and endpoints, according to the experts. If it’s true that there are mental and physical health benefits to marriage, they are likely small. Moreover, an unhappy marriage doesn’t yield health benefits, and those who divorce—from ostensibly unhappy unions—exhibit rebounding health in subsequent years. One possibility is that marriage improves worldview and well-being rather than objective health measures.