Legal marriage may be a boon for the health of same-sex couples, according to new research that finds cohabitating doesn't provide the same health benefits for gay couples that marriage does for straights.
The research echoes previous work released last year, which found married gay couples are happier than those in domestic partnerships or those who are single. Marriage is also linked to happiness among straight couples.
"Past research has shown that married people are generally healthier than unmarried people,” Michigan State University sociologist Hui Liu, who led the new study, said in a statement. "Although our study did not specifically test the health consequences of legalizing same-sex marriage, it's very plausible that legalization of gay marriage would reduce health disparities between same-sex cohabitors and married heterosexuals.”
Health and relationships
Liu and his colleagues used nationally representative data from the National Health Interview Surveys, an ongoing study run by the U.S. Census Bureau. As part of the survey, respondents rated their physical health as excellent, very good, good, fair or poor.
The data in the current study came from 1,659 same-sex cohabitating men and 1,634 same-sex cohabitating women. The researchers compared these couples with straight married couples, cohabitating heterosexual couples as well as single, divorced and widowed individuals. Respondents were between 18 and 65 years old and answered the survey questions between 1997 and 2009.
After taking socioeconomic status into account, the researchers found that same-sex cohabitating men were 61 percent more likely to report only fair or poor health compared with men in heterosexual marriages. Women in same-sex cohabitation relationships were 46 percent more likely to report fair or poor health than married straight women. [5 Myths About Gay People Debunked]
The findings are correlational, meaning researchers cannot prove that the relationship arrangements directly caused the health responses. However, Liu and his colleagues did control for factors such as income and ethnicity that would affect the results.
Same-sex cohabitors were actually healthier than opposite-sex cohabitors, the researchers found, but the effect vanished when taking into account socioeconomic status. In other words, same-sex couples who cohabitate are better off economically than opposite-sex couples who chose to live together unmarried, and their extra health benefits stem from that economic security.
Why marriage might matter
Numerous studies have found that sexual minorities suffer discrimination and heightened stress compared with straight people, Liu said, which could explain why same-sex couples reported feeling less healthy.
Same-sex cohabitation may also fail to bring the same benefits as legal marriage, he said.
"Legalizing same-sex marriage could also provide other advantages often associated with heterosexual marriage — such as partner health insurance benefits and the ability to file joint tax returns — that may directly and indirectly influence the health of individuals in same-sex unions," Liu said.
The researchers report their findings in the March issue of the Journal of Health and Social Behavior.
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Stephanie Pappas is a contributing writer for Live Science, covering topics ranging from geoscience to archaeology to the human brain and behavior. She was previously a senior writer for Live Science but is now a freelancer based in Denver, Colorado, and regularly contributes to Scientific American and The Monitor, the monthly magazine of the American Psychological Association. Stephanie received a bachelor's degree in psychology from the University of South Carolina and a graduate certificate in science communication from the University of California, Santa Cruz.