Will Antibiotics Make Your Baby Fat?
A new study raises questions about the long-term effects of antibiotic use in infants
Over-use of antibiotics has long been blamed for the rise of drug resistant “superbugs.” Now, they may also be partly to blame for the childhood obesity epidemic, according to a new study from New York University that shows infants treated with antibiotics tend to be heavier than those who are treated without them.
The NYU School of Medicine researchers looked at antibiotic use among over 11,000 children born in the United Kingdom during 1991 and 1992. On average, infants prescribed antibiotics at any point from birth to 5 months of age weighed more for their height than babies who didn’t use antibiotics; by their third birthdays, the early antibiotics users had a 22 percent greater likelihood of being overweight. Using antibiotics for the first time a few months later—from 6 months to 14 months—appeared to have no effect on childhood weight.
Researchers say their study does not prove that antibiotics in early life cause young children to be overweight. But it does appear to show a newly discovered relationship.
“We typically consider obesity an epidemic grounded in unhealthy diet and exercise, yet increasingly studies suggest it’s more complicated,” said Leonardo Trasande, M.D., MPP, associate professor of pediatrics and environmental medicine at NYU School of Medicine, and one of the study’s lead authors.
How do antibiotics lead to weight gain? It may be because in their quest to go after bad bacteria, antibiotics also kill off “good bugs” in the gut that are helpful for weight regulation.
“Microbes in our intestines may play critical roles in how we absorb calories, and exposure to antibiotics, especially early in life, may kill off healthy bacteria that influence how we absorb nutrients into our bodies, and would otherwise keep us lean,” explains Trasande.
What do moms think about this study? “My baby never needed an antibiotic at this age, thankfully, but with all the stuff that’s coming out about antibiotics, if I had a little one right now, I would want to really understand why our doctor thought medication was needed,” says mom Ann Conlin of Clifton Park, New York.
Amy Brown’s son took antibiotics early on when he developed a series of severe ear infections starting at 3 months old. Her take? “My son is 9 and a string bean. When he was a baby, he really needed antibiotics, so he got them. The last thing on my mind was whether he would be a little bit heavy three years later!”
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