“Compared to those managing conflict in positive ways like working together and validating each other’s perspectives, those who deal with conflict by rolling their eyes, speaking in a hostile tone, or criticizing their partners are more likely to have higher inflammation, higher stress hormones, and delayed wound healing,” says Shrout.

“Our brain is wired for social connection, and it’s the quality of those connections that profoundly influences our mental and physical health,” echoes Stephanie Cacioppo, a neuroscientist at the University of Oregon, who researches the effects of relationships on health. “Without a deep emotional connection, the protective benefits of marriage might not fully materialize.”

Benefits that last into the golden years

The good news is that when one is in a loving, committed marriage, research shows that the health benefits of mid-to-later-life marriages can be as profound as the marriages of people who wed much earlier. “The benefits of being married remain constant for those over age 60 and beyond,” says Kao. 

In some ways, later-life marriages may even be more beneficial to single people as that’s when preventative screenings are more important, hospital care is more likely, and musculoskeletal strength begins to decline. Older couples can help each other through such times and keep each other stronger and more active, explains Peter Martin, a human development and family studies professor at Iowa State University.

People in their sixties are also twice as likely to experience social isolation than younger adults, making the presence of a constant companion—spouse or otherwise—even more vital in staving off the dangers of loneliness.