A new study by Carnegie Mellon University may change your view on marriage if you still insist on being single. "Married people tend to be healthier than both the previously ... and never married, but the mechanisms through which this occurs remain unclear," researchers say, according to ScienceDaily.Published in the Psychoneuroendocrinology journal, the study has found that married couples have lower levels of the stress hormone cortisol than singles or divorced individuals. The results emphasize the prolonged psychological stress that unmarried people experience, which increases the level of cortisol in the human body. "Research has increasingly focused on how psychological stress experienced by unmarried versus married individuals may differentially impact physiological systems related to health."To carry out the study, the researchers examined collected saliva samples from adults aged between 21 and 55. "It is exciting to discover a physiological pathway that may explain how relationships influence health and disease," said Brian Chin, a Ph.D. student in the Dietrich College of Humanities and Social Sciences' Department of Psychology.