Dad bod is real! First-time fathers experience weight gain and an increase in body mass index, a new study on more than 10,000 men has found.
In one of the first studies to examine how fatherhood affects BMI, researchers tracked the weight of more than 10,000 men from adolescence to young adulthood.
They found that a typical 6-foot-tall man who lives with his child gained an average of about 1.9 kg after becoming a first-time dad.
The 6-foot-tall father who does not live with his child gained about 1.5 kg.
That amounts to a 2.6 per cent rise in BMI for resident dads and a 2 per cent rise in BMI for non-resident dads.
By contrast, the average 6-foot-tall man who was not a father actually lost 0.6 kilogrammes over the same time period.
The study controlled for other factors that could contribute to weight gain such as age, race, education, income, daily activity, screen time and marriage status.
It is already known that marriage results in weight gain for men. The fatherhood weight gain is in addition to the increase resulting from marriage, the researchers said.
"Fatherhood can affect the health of young men, above the already known effect of marriage," said lead author Craig Garfield, associate professor at the Northwestern University Feinberg School of Medicine.
"The more weight the fathers gain and the higher their BMI, the greater risk they have for developing heart disease as well as diabetes and cancer," Garfield said.
New fathers' weight gain may be due to changes in lifestyle and eating habits, the researchers said.
"You have new responsibilities when you have your kids and may not have time to take care of yourself the way you once did in terms of exercise," Garfield said.
Eating habits may shift as the house fills with cookies, ice cream and other snack food.
"We all know dads who clean their kids' plates after every meal," Garfield said.
Over the 20 years of the study, all 10,253 participants had their BMI measured at four different time points - early adolescence, later adolescence, mid-20s and early 30s.
Each participant was categorised either as a non-father, resident father or non-resident father. Then researchers looked at each person's BMI at each time point and took the average of all those measurements to determine whether their fatherhood status was associated with their BMI.
Since many new dads don't have a personal physician, pediatricians are in a good position to counsel dads about taking care of their health, the researchers said.
The study was published in the American Journal of Men's Health.
