Kids who had been exposed to antibiotics at least four times before age two were 11 percent more likely to be obese later than kids who had not been exposed to any antibiotics.
That’s a small change in risk for individual kids, but since obesity is so common and has so many causes it is important to track down as many of these causes as possible, Bailey said.
Other than the antibiotics, the cause of the increased risk of obesity may also be the disease that the child got the medication to treat, Bailey noted.
Additionally, he said that having other family members who are obese, whether or not an infant is breastfed, and an infant's diet and activity are also connected to later obesity risk.