Being married, having close friends and family members may lead to better mental and physical health in older adults, according to a recent study.

Researchers from Carnegie Mellon University in Pennsylvania found that belonging to social and religious groups may positively impacts pulmonary function in the elderly. Lung function, which decreases with age, is an important physiological quality that affects cardiovascular disease, asthma and other lung disorders.

"We knew that when older adults have friends and family and belong to groups, they have lower mortality rates and less disease and illness risk, but now we can start to understand why that happens," Sheldon Cohen, the Robert E. Doherty University Professor of Psychology in CMU's Dietrich College of Humanities and Social Sciences, said in a statement.

For the study, the research team analyzed data collected from more than 1,000 healthy adults between the ages of 70 and 79 who participated in the MacArthur Study of Successful Aging. The data included a measure of the participants' social roles and assessed their pulmonary function according to peak expiratory flow rate (PEFR).

The researchers found that the more social roles people engaged in, the better their lung function. While analysis of specific social roles indicated that marriage was the strongest positive connection to lung function, greater numbers of roles also were associated with better lung function even in those who were not married. Being a relative or a friend were also individually linked to improved lung function, but more social roles also were associated with better lung function independent of being a relative or a friend.

"Older people need to get out because any sort of social interaction will improve their health," Crista Crittenden, lead author of the study and a visiting assistant professor of psychology at Carnegie Mellon in Qatar, said in a statement. "I am really interested in how social and psychological factors influence lung health, and not only have we shown that more social roles, like being married or having friends, improve lung function, we found a link between more social roles and increased happiness and physical activity that could also help with lung function and overall health."