Most men gain a new sense of responsibility and purpose in life when they become fathers. A new study suggests, on an average they also gain up to 2.3 kg.
Dr Craig Garfield of Northwestern University, the lead author of the study published Tuesday by the American Journal of Men's Health, said he could only speculate about what's behind the extra weight.
"For men who become fathers, their whole life changes," Garfield said. They may sleep less, exercise less, and experience more stress - all of which can lead to weight gain, he said.
It doesn't help that the food selection at home may gradually change to include more things like "making chocolate chip cookies with the kids," said Garfield.
For their work, the researchers looked at results from another study, which tracked the health of adolescents over two decades. The researchers focused on teen boys and young men, comparing weight changes in the 3,400 who became dads and the 6,800 who didn't.
There was a difference.
After becoming a first-time dad, a typical 6-foot-tall man who lives with his child will gain an average of about 2 kg, the study suggested. A same-sized man who does not live with his child can expect to gain nearly 1.6 kg.
But a 6-foot man who does not have children typically loses about 700 gm over the same time period, researchers found.
The study found men who lived with their children were a little heavier to begin with, on average, and ended up heavier than the absent fathers and the men who didn't have kids.
Nearly three-quarters of US men are overweight or obese, according to government statistics.