It may seem contradictory to the plots of countless classic sitcoms, but a new study suggests marriage may very well be the best thing for you.  

While past research has suggested married people tend to be healthier than those flying solo, a new study from Carnegie Mellon University provides the first biological evidence to explain marriage’s effect on health.

The study, published in Psychoneuroendocrinology, found that married people had lower levels of the stress hormone cortisol, compared with those who were never married or who were once married.

The study supports long-held theories that single people have more psychological stress than married couples. Persistent stress is linked to increased levels of cortisol, which can get in the way of the body’s ability to fight off disease.  

"It is exciting to discover a physiological pathway that may explain how relationships influence health and disease," said Brian Chin of the Dietrich College of Humanities and Social Sciences' Department of Psychology.

The researchers gathered saliva samples from 572 healthy adults over three days. Once the samples were tested for cortisol, the researchers noticed that married participants had lower cortisol levels than single participants.

"These data provide important insight into the way in which our intimate social relationships can get under the skin to influence our health," said co-author Sheldon Cohen of the Robert E. Doherty University Professor of Psychology.

It seems a happy wife means more than just a happy life – it means a healthy one, too.

h/t Science Daily