Legal access to same-sex marriage leads to improved health for gay men, according to a new paper published by the National Bureau of Economic Research (NBER).

The report found access to gay marriage — even at the state level before its national legalization in 2015 — improved men’s health by significantly increasing the probability they would have health insurance, a primary-care physician and regular checkups.

“Legal access to SSM (same-sex marriage) significantly increased marriage take-up for gay and lesbian couples and also significantly improved healthcare access and utilization for adult gay men in same-sex households,” the report stated.

Prior to the Supreme Court’s landmark 2015 ruling in Obergefell v. Hodges, which legalized same-sex marriage across the U.S., individual states had varying marriage laws. The report’s authors exploited these legal disparities and — along with household surveys conducted by the Centers for Disease Control and Prevention (CDC) — were able to research the health effects of same-sex marriage access.

If same-sex marriage was legal in their state, the researchers found men living in a two-person, same-sex household were 4.2 percent more likely to have health insurance and a regular provider of medical care. They were also 7.3 percent more likely to have had a routine check-up in the past year.

While researchers had expected to find health benefits for gay men with legal access to same-sex marriage, not all of their findings matched the expectations they had prior to parsing the data.

“We hypothesized that same-sex marriage would lead to better health and better access to care for men and women,” Gilbert Gonzales, one of the report’s authors, told NBC News. “We were surprised not to find it.”

Legal access to same-sex marriage was also not found to significantly change certain unhealthy behaviors, including heavy drinking and smoking, which also contradicted the research team’s expectations.

Gonzalez said there are a few reasons why the team’s more ambitious hypothesis may not have panned out. Gonzalez noted it could be too early to determine all the health effects legal access to same-sex marriage may have on individuals. He also said a change in marriage policy may not be enough to have a bigger health impact on LGBTQ people. After all, he said, gay marriage “doesn’t mean that discrimination or stigma are going to go away immediately.”

In terms of the report’s main finding — the health benefits for gay men associated with access to same-sex marriage — Gonzalez said he has witnessed these health benefits firsthand.

“My partner and I had just moved to Tennessee, and because of the Supreme Court decision in 2015, we were able to get married, and my partner joined my health plan,” Gonzales explained. “I know many couples in Tennessee who also benefit from same sex marriage … They're enrolling in their partners' employer health plans.”

In 2017, 84 percent of employees working at firms with spousal health care benefits also reported access to same-sex spousal benefits, according to a Kaiser Family Foundation report.

The benefits of legal marriage are not unique to gay men. Marriage between a man and a woman has consistently been linked to health benefits, including higher disease survival rates and lower rates of depression. Support from a spouse can be physical, emotional and — in the case of employer-sponsored health insurance — financial.

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