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Jon Hamm is rocking the dad bod look.
Men with a dad bod have a "nice balance between a beer gut and working out," as defined by Clemson University student Mackenzie Pearson, who first brought the term to the Internet's attention back in March.
And, as it turns out, many men do put on a few pounds after their children are born, which likely contributes to this fit-but-flabby body type.
In the first study of this size, researchers at Northwestern Medicine kept track of the height and weight of about 10,000 men for 20 years, starting in 1994 when they were between 12 and 21 years old. By 2008, a third of them had become dads.
Those who became fathers for the first time gained anywhere from 3.5 to 4.5 pounds over that two-decade period, regardless of whether or not they lived with their kids.
The average 6-foot-tall father who lived with his kids gained about 4.4 pounds, while the average 6-foot-tall father who didn't live with his kids still gained about 3.3 pounds. In contrast, men of the same height who did not have kids actually lost weight - 1.4 pounds, to be exact - over that same time.
Numerous other studies have connected weightgain to fatherhood, but this is the first of its kind to look at BMI, which can be an indicator of one's proportion of body fat and point to potential health problems. The researchers found that the BMI for dads living with their kids increased by 2.6%, while the BMI of dads who lived elsewhere increased by 2%. The higher the BMI, the more the men are at risk for diseases like diabetes, cardiovascular disease, and cancer.
Not great news for the little tot or the spouse.
The researchers only collected numbers - they didn't try to explain their findings. But they mention some potential guesses, like dads who nosh on their kids' leftovers or put off exercise in favor of spending more time with kids.