By Dr. Brian McDonough, Medical Editor

PHILADELPHIA (CBS) - Are you a young parent who is tired and looking for a break? Maybe you are jealous of your single friends because they have more freedom. Or are you someone who thinks that if you have children, every day with them is a gift?

The truth is probably somewhere in the middle but when it comes to health a new study has good news for parents.

Parents are about half as likely to catch a cold as people without children, regardless of their preexisting immunity.

According to the researchers, unknown psychological or behavioral differences between parents and nonparents might help explain their findings.

The work is from Carnegie Mellon University. And there is more. This protective effect increased along with the number of children parents had.

The study, which is published in the journal Psychosomatic Medicine, also found that being married had no effect on the findings.