A new large-scale study shows married couples diagnosed with cancer live longer.

Traditional wedding vows involve the phrase “until death do you part,” but a new study suggests that getting hitched can translate to departing later in life.

Researchers at Dana-Farber Cancer Institute in Boston say people who are married when diagnosed with cancers have much better outcomes.

Specifically, unmarried patients are 17 percent more likely to have metastatic cancers—cancer that has spread from its point of origin—and 53 percent less likely to receive the appropriate therapy, according to a study in the Journal of Clinical Oncology.

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Researchers discovered marriage’s protective effects by examining cancer records of 734,889 people from 2004 to 2008 in the National Cancer Institute’s Surveillance, Epidemiology and End Results Program. Researchers focused on the 10 most common cancer deaths in the U.S.: lung, colorectal, breast, pancreatic, prostate, liver/bile duct, non-Hodgkin lymphoma, head and neck, ovarian, and esophageal cancer.

Adjusting for other factors, the Dana-Farber team discovered the benefits marriage can have on a cancer diagnosis.

“Our data suggests that marriage can have a significant health impact for patients with cancer, and this was consistent among every cancer that we reviewed,” Dr. Ayal Aizer, chief resident of the Harvard Radiation Oncology Program and the paper’s first author, said in a statement.

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Researchers said the survival rates are propelled by the social support of a spouse, namely because they often accompany the patient to doctor visits and aid in asking questions or making sure their partner adheres to a doctor’s recommendations.

With or without formal vows, the study’s senior author, Dr. Paul Nguyen, a radiation oncologist at Dana-Farber, said the results show how doctors should encourage the needed social support at such a difficult time in a person’s life.

“We don’t just see our study as an affirmation of marriage, but rather it should send a message to anyone who has a friend or a loved one with cancer: by being there for that person and helping them navigate their appointments and make it through all their treatments, you can make a real difference to that person’s outcome,” he said.

In an accompanying editorial—“Marriage Is as Protective as Chemotherapy in Cancer Care”—David W. Kissane of Memorial Sloan-Kettering Cancer Center in New York City said taking the mindful, protective mindset of a caring spouse into the greater community could have larger implications on national health.

“Our humanity is relational at its essence—we are tribal people, drawn into connection with one another to share what is most meaningful and fulfilling in life. Our medicine needs to follow a parallel paradigm: healing care that is both person- and family-centered in its expression,” researchers wrote.