Clamps, scissors and other surgical instruments are seen in the...

Clamps, scissors and other surgical instruments are seen in the operating room during a kidney transplant at Johns Hopkins Hospital in Baltimore, Md. Credit: Getty Images

When I mentioned my bout with breast cancer to a new acquaintance, his first question was, "Are you married?"

It was an unusual reaction - a more common query is whether I have kids. Later he told me that his daughter-in-law had been diagnosed with breast cancer while still in graduate school and that she and his son had moved in with him. He understood better than most people that being married makes it easier to cope with cancer.

The very next day the Journal of Clinical Oncology released a study offering more than anecdotal evidence that marriage is good for cancer patients.

Controlling for demographic factors such as age, race, education and household income, researchers who analyzed records of more than 730,000 cancer patients found that married patients did significantly better than single people. They lived longer, received better treatment and were more likely to be diagnosed before metastatic cancers developed.

It didn't matter whether the unmarried patients were lifelong singles, divorced, widowed or separated. All did worse than demographically similar married patients.

"This study is the first to show a consistent and significant benefit of marriage on survival among each of the ten leading causes of cancer-related death in the United States - lung, colorectal, breast, pancreatic, prostate, liver/bile duct, non-Hodgkin lymphoma, head and neck, ovarian, and esophageal cancer," the American Society of Clinical Oncology noted in its news release.

The study doesn't explain exactly why marriage makes a difference. It's possible that married patients just have better health insurance. But, the authors note, "even in nations with universal access to free care, such as Denmark, sociodemographic factors affect outcome in a multitude of health conditions." (Insurance differences also wouldn't do much to explain the disadvantage of widowhood, because widows tend to be covered by Medicare.) "The most likely reason," the authors conclude, "is that married patients have better adherence with prescribed treatments than unmarried patients." They have someone to watch over them.

What about couples who aren't formally married but in long- term relationships? What about widows with supportive kids? What about people with great friends? And what about unhappy marriages? The study didn't leave these people out. If it had - if it had measured only the difference between ideal marriages and lonely, miserable singles - the differences would presumably be even more distinct. In the big picture, marriage makes a difference.

Marriage is increasingly the big sociological divide in American life. Getting and staying married makes you part of a privileged elite.

As Charles Murray documents in his 2012 book "Coming Apart," that divide tracks the income divide, with low-income whites much less likely to be married than their high-income counterparts. (I criticized a different aspect of Murray's book in this column.) The causality is debatable. Maybe poorer people have a harder time getting married. Maybe being married makes it easier to earn more. Maybe some third factor causes both phenomena. But what is clear is that you're most likely to have a better life if you're married - even if, it turns out, you get cancer.

Friends are nice, but they are rarely equivalent to a spouse. The level of on-call commitment and intimacy is simply different. Your spouse knows you in a 24/7 way that few if any others do, especially in a society organized around the nuclear family rather than the extended one. (A spouse also multiplies your extended family by two.) As my economist husband likes to put it, being married also creates a "joint utility function." Your happiness becomes entwined with your spouse's, giving you strong incentives to make an extra effort.

Recalling how the "epidemic of care giving" in response to AIDS helped make the case for same-sex marriage, the writer Jonathan Rauch argued that by "assuming the burdens of marriage at its hardest," gay men demonstrated that "no relative, government program or charity is as dependable or consoling as a dedicated partner." What's true of AIDS is true of cancer as well.

People don't like to hear that. It's not fair to single people. It's not constructive. "Our results suggest that patients who are not married should reach out to friends, cancer support or faith-based groups, and their doctors to obtain adequate social support," lead author Ayal Aizer, chief resident in radiation oncology at Harvard Medical School, said in the oncology society's news release.

But trying to turn the study's findings into a general call for "social support" ignores its stark result. Single people aren't, of course, doomed to die of cancer. Their friends and family can in fact help them do better. But we shouldn't pretend that marriage isn't a huge advantage.

Virginia Postrel is a Bloomberg View columnist. Her next book, "The Power of Glamour," will be published Nov. 5 by Simon & Schuster.


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