And the more children you have the strong the affect, the study from the Carnegie Mellon University in the US found. While parents with one or two children were 48 per cent less likely to get sick, those with three or more children were 61 per cent less likely to develop a cold, it found.
Surprisingly the scientists don't think this is because parents have immune systems that have been strengthened by constant viral attacks. Instead it comes down to "mental toughness", they claimed.
This explains why parents with children living at home and away from home showed a decreased risk of catching a cold, said Prof Sheldon Cohen who led the study. "Although parenthood was clearly protective, we were unable to identify an explanation for this association," Cohen was quoted as saying by the Daily Mail.
He said: "Because we controlled for immunity to the virus, we know that these differences did not occur just because the parents were more likely to have been exposed to the virus through their children.
"Moreover, parents and nonparents showed few psychological or biological differences, and those that did exist could not explain the benefit of parenthood. "We expect that a psychological benefit of parenthood that we did not measure may have been responsible."
For the study, published in Psychosomatic Medicine, Prof Cohen and his team exposed 795 healthy adults between the ages of 18 and 55 to a virus that causes a common cold.
The 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.
Overall non-parents were half as likely to develop colds than parents, the researchers found. Prof Cohen said: "We have had a long-term interest in how various social relationships influence health outcomes.
"Parenthood was especially interesting to us because it has been proposed that it can have both positive and negative effects on health. For example, being a parent can be stressful but at the same time can be fulfilling, facilitate the development of a social network and provide purpose in life."