A study conducted by researchers from Northwestern University revealed that men tend to gain weight when they become fathers for the first time.

Study lead author Craig Garfield said in a statement that the more the new fathers gain weight and body mass index (BMI) the greater is the risk of developing heart disease, diabetes and cancer.

Researchers for the study tracked weight of more than 10,000 men from adolescence to young adulthood for 20 years, reported ABC News. As the time passed, BMI of the study participants was measured at four different time points i.e. early adolescence, later adolescence, mid-20s and early-30s.

Researchers categorized each participant either as a non-father, resident father or non-resident father. Then researchers looked at each person’s BMI and took the average of all those measurements to determine whether their fatherhood status was associated with their BMI.

Researchers found a difference in the weight gained by fathers who lived with their kids and those who do not, the Washington Post reported.

They also found that a 6-foot-tall man who lives with his child gained an average of about 4.4 pounds after he became father for the first-time whereas another 6-foot-tall man who does not live with his child gained about 3.3 pounds, the study found.

Changes in lifestyle and eating habits could be responsible for weight gain in first-time fathers.

“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. Your family becomes the priority”, Garfield said.