A new study solved the mystery of the dadbod by proving becoming a father does, in fact, lead to weight gain.
According to The Washington Post, researchers at Northwestern University's Feinberg School of Medicine examined the BMI (body mass index) measurements of 10,253 men; the data was collected over the course of 20 years.
The researchers obtained data throughout four periods of the participants' lives, from early adolescence and to the early 30s.
New fathers gained weight regardless of race, education, income and even marriage status.
There was a slight difference, however, in the weight gain of fathers who lived with their children and those who did not.
Fathers who lived with their children saw their BMI increase by an average of 2.6 percent over the study's time span, while fathers who didn't saw their BMI go up by 2 percent in the same period.
When height was taken into account, the study found the average 6-foot dad who lives with his child gains 4.4 pounds compared to a 3.3 pound increase for a dad who doesn't live with his child.
It has already been proven getting married causes weight gain, but researchers discovered as long as he didn't have kids, the average 6-foot-tall man actually lost 1.4 pounds over the study period.
The researchers called their estimates for the increases in BMI and weight gain "conservative," which suggests a number of participants experienced much more significant changes.
In a press release, lead author and Northwestern Associate Professor Craig Garfield said,
Fatherhood can affect the health of young men, above the already known effect of marriage. 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 attributes the weight gain to the lack of time new dads have for exercise due to the new responsibilities they must take on in raising their children.
The findings, he added, show new dads are in great need of solutions for breaking this trend since it could result in their children gaining weight as well.
We now realize the transition to fatherhood is an important developmental life stage for men's health.
The American Journal of Men's Health originally published the study.