Like Marriage, Committed Relationships May Protect Against Stress

By Sharon Jayson, USA TODAY

Studies have long shown that married people are less susceptible to the effects of stress. Now a new study finds that being in a committed relationship, even without being married, appears to have the same protective effect, according to a study published in the journal Stress.

A research team from the University of Chicago and Northwestern University in Evanston, Ill., studied 501 masters of business administration students (348 men and 153 women) and found the romantic bond of being in a committed relationship alters hormones that can buffer against stress.

Participants were asked to take a 90-minute computerized test in which they played games that assessed their economic decision-making. They were told the test was a course requirement and the results would impact their future career placement, so that the test was a potentially stressful experience.

Before and after the test, researchers took saliva samples to measure cortisol and testosterone two hormones that the study says "are particularly sensitive to psychological and social influences." Cortisol is often called the stress hormone. Testosterone can potentially influence responses to take risks.

The study found cortisol concentrations increased for all participants, but the results suggest that single people were more susceptible to psychological stress than those who are married or in a relationship, says study co-author Dario Maestripieri, a University of Chicago professor of comparative human development, evolutionary biology, neurobiology, and psychiatry.

"The magnitude of the increase how much it went up related to whether they were in relationships," he says. "The ones who were married or in relationships had less of an increase. Somehow, they were protected from stress. They were better able to cope. For the ones that were single, cortisol really shot up."

About 40% of men and 53% of women in the study were married or in a relationship.

Men had higher concentrations of testosterone and cortisol than did women, both before and after the test. The research found single men, in general, have higher testosterone than men in stable relationships or who are married.

"We don't know whether it's the result of being single or you have high testosterone and that makes you more likely to be single and less likely to settle down in a stable relationship," Maestripieri says.