For better or worse, for richer or poorer, til death do you part...
The institution of marriage has gone through a radical transformation over the past few decades, including a rising divorce rate, the redefinition of marriage itself, and the rise of common-law marriage as an alternative to traditional marriage. Still, psychologists and researchers have been investigating how quality of marriage affects psychological well-being for decades. Fairly consistently, research looking at different measures of marital satisfaction has linked having a strong marriage to life satisfaction, general happiness, and mental health.
But does having a good marriage improve physical health as well? Various reviews published over the past few decades indicate that it does, though those studies have been relatively limited to date since they largely focus on comparing married and non-married individuals. Newer research studies have found that simply having a strong social support network can have powerful health benefits. Only recently have research studies investigated whether the benefits of marriage are necessarily greater than other types of long-term committed relationships that many people have as an alternative.
Two possible explanations have been suggested for why intimate relationships can improve health. First of all, being integrated into a strong social support network provides people with a sense of identity, purpose, and control as well as getting positive reinforcement for behaviours that promote health (and punishment for behaviours that are harmful to health). Also, having strong social support through meaningful relationships can help protect people from the daily stress that we all experience. This protection can come from the emotional support we receive as well as the active help people in our social support network can provide.
While this social support can come from family and friends, intimate relationships, such as what we experience in marriage, can be critical to our emotional needs. Not only do married spouses share most of their daily activities, they also share financial resources, childcare responsibilities, domestic chores, and sleep. This joint sharing means that marriage represents a unique source of both emotional support and possible conflict. While modern redefinitions of marriage have led to more alternatives for couples wishing to share their lives, the impact that this sharing has on physical health, whether through formal marriage or a common-law relationship has been largely overlooked up to now. Still, formal marriage remains the most popular choice for adults overall. According to United Nations statistics, over 90 percent of adults in most countries describe themselves as having been married at some point in their lives
A new meta-analytic study published in Psychological Bulletin examined 126 research studies published over the past 50 years looking at the relationship between marital relationship and physical health for more than 70,000 individuals. Led by Thomas F. Robles of the University of California at Los Angeles, the researchers conducting the study examined different measures of marital relationship quality and health as well as different demographic and medical factors involved. The study defined marital quality as "global self- or other-reported evaluation of the marriage and/or behaviors within the marriage, in terms of positive dimensions (happiness, support, satisfaction) and negative dimensions (conflict, tension, strain)." Since relying on self-reports can be a problem in measuring marital satisfaction, the researchers focused on behavioural ratings instead.
Along with health surveys to measure medical history and activities of daily living, the studies examined by Robles and his fellow researchers also included data on cardiovascular reactivity and related biological health markers. Though more than 350 studies were considered for the meta-analysis, only 126 studies were considered rigorous enough to examine further. In all, the studies included in the meta-analysis looked at 72,000 people with samples taken from Brazil, Canada, Finland, Germany, Hong Kong, Israel, the Netherlands, Sweden, the United Kingdom, and the United States.
Overall, despite wide variations, greater marital quality is related to greater physical health. Poorer marital quality, on the other hand, was a significant predictor for a wide range of health problems, including lower cardiovascular reactivity. While the effect sizes are relatively small (in the r = .20 range), they are still significant considering the large sample sizes involved. In fact, the effect sizes are equivalent to the results of medical studies linking exercise and diet to good health. For people with serious medical conditions, including heart and kidney disease, marital satisfaction was significantly correlated with living longer. Even when other factors such as age and medical history were taken into account, the link between marital satisfaction and health remains strong.
As for results linking marital quality to mental health, the relationship between marital satisfaction and depression was fairly strong for both men and women (with correlations ranging from .37 to .42). Greater marital quality was also linked to greater psychological well-being including self-esteem, life satisfaction, and happiness with larger effect sizes than with measures of physical health.
According to Robles and his colleagues, though this meta-analysis suggests a strong link between marital satisfaction and health, the question of why this link exists is harder to determine. While there seems to be a strong link between marital unhappiness and depression, that relationship is not enough to explain the health effects of marital quality. On the other hand, people in happy relationships seem more likely to follow medical advice and stick to diet and exercise routines that can ensure good health. One study linked marital happiness to better self-care for diabetes patients while other studies showed similar results with other serious illnesses. Marital satisfaction was also linked to fewer sleep problems which could be another factor in ensuring good health.
Emotional support may be another factor linking marital satisfaction to good health. How willing people are to open up to their spouses about thoughts and feelings appears to be linked to lower cortisol levels and other physiological measures of stress. Whether these same health benefits persist over time and in different kinds of stressful situations still remains to be seen, however. Other factors such as age, length of marriage, and socio-economic status may be important as well.
Robles and his fellow researchers also compared the effect size linking marital quality to good health to other lifestyle factors associated with health. Though there were only a small number of studies allowing direct comparison, marital quality appears to play a stronger role in promoting good health than factors such as not smoking, controlling drinking, and curbing caffeine. Only exercise and good nutrition were stronger predictors of positive health outcomes. The relationship between marital quality and health also appears fairly stable over time since the meta-analysis looked at studies completed over the past fifty years.
While gender differences were fairly small in general, spouses who are less powerful in their relationship (more dependent on the other person) experience greater levels of stress during conflicts. Even in dual-income households, the spouse who spends more time on housework at the end of the day is also more stressed overall. The dominant spouse (regardless of gender) also shows better cardiovascular performance.
As for same-sex couples, making direct comparisons is more difficult since same-sex marriage is still illegal in most U.S. states and the legalization to date is still too new for significant research to be completed. Available research to date suggests that same- and opposite-sex couples have a similar association between marital quality and health. If anything, research has shown that same-sex couples are more likely to engage in effective problem-solving and to not have the same gender disparities found in opposite-sex couples.
So, what do these results suggest for the future? While further research still needs to be done to explore this link between marital satisfaction and health, recognizing that improving marital happiness can be important in helping people with serious illnesses. Couples therapy can help with patients experiencing chronic pain or depression and is being extended to patients with other illnesses such as breast cancer. Although treating serious illnesses often requires looking at the "whole person", doctors may be reluctant to explore how marital happiness is affecting patient treatment since it is often something beyond their control. Encouraging couples to become partners in dealing with health issues may pay more dividends than anyone realizes.