New research provides the first evidence that, when exposed to a common cold virus, parents are 52 percent less likely to develop a cold than non-parents.

The study by Carnegie Mellon University exposed 795 healthy adults age 18 to 55 to a virus that causes a common cold. Participants reported their parenthood status, and analyses were controlled for immunity to the experimental virus, viral strain, season, age, sex, race, ethnicity, marital status, body mass, employment status and education.

Parents with one or two children were 48 percent less likely to get sick while parents with three or more children were 61 percent less likely to develop a cold. Both parents with children living at home and away from home showed a decreased risk of catching a cold. And, while parents older than age 24 were protected from the cold virus, parenthood did not influence whether those aged 18-24 became ill.

The reason was unclear. "We expect that a psychological benefit of parenthood that we did not measure may have been responsible," said Sheldon Cohen, the Robert E. Doherty Professor of Psychology within CMU's Dietrich College of Humanities and Social Sciences.

Read the study from Carnegie Mellon University.