The 'Dad Bod' exists, study says

Marc Cugnon
USA TODAY Network
Young males' body mass index (BMI) numbers actually do increase during the transition from adolescence to fatherhood.

The increasingly popular "dad bod" is more than just a viral trend. Children do impact men's waistlines, according to a new study.

The study, spearheaded by Craig F. Garfield, an associate professor in Pediatrics-Hospital-Based Medicine and Medical Social Sciences at Northwestern University, has proven that young males' body mass index (BMI) numbers actually do increase during the transition from adolescence to fatherhood.

Through an examination of 10,253 men over a period of 14 years, the team revealed the science behind the "dad bod."

(For anyone who needs a refresher, the "dad bod" is defined is a man who looks as if he may frequently go to the gym, but a thick layer of belly fat reveals a high-carb, junk-food and beer-induced diet.)

The research team also demonstrated how a number of outside factors, including socio-economic status and race, can affect the development of this type of body.

Young men who became "resident fathers" (essentially, men who live at home with their child and, usually, wife), demonstrated a 2.6% larger BMI increase on average than non-fathers, of similar age, over the same period of time, according to the study from Northwestern University's Feinberg School of medicine.

The researchers also uncovered a correlation between race and BMI increases following the birth of one's first child. While Caucasians and Asians were typically on the lower end of BMI upticks, Blacks and Latinos were often near the higher end of the spectrum, the study found.

"Having a kid is a major life event," Thom McDade, a Northwestern University professor and member of the study's research team said. "It turns your life around in a number of ways. You don't sleep as well, you might not eat as well as you're used to and you may not have as much time to participate in sports, or maintaining personal health because you prioritize your children or spouse," he said.

"The good news is that these are all short term challenges. Once you come out of the fog of having a child, you can work your kid into exercise and learn how to sleep better, and work through things," said McDade.

Non-resident fathers, or individuals who do not live with their children, also demonstrated variations in their BMI increase. While resident fathers often experience a BMI increase prior to fatherhood, non-resident fathers usually decrease in average BMI during this same period.

However, non-resident fathers, the study claims, are at a high risk for increased BMI in early fatherhood. Usually, McDade added, resident fathers boast a higher level of income and education than non-resident dads, both factors that are associated with better health.

“I think the study is a wake-up call to the important time that becoming a father is for men," Garfield said.  "We’re just starting now to understand the social determinants of health. Doctors ask women about their past pregnancies and histories of breastfeeding, because we know about the impact these have on them. We don’t ask men about things like this."