Can Reduced Antibiotic Misuse Prevent Childhood Obesity?

A new study published this week in Obesity raises an important question. Can reducing antibiotic misuse for infants be an effective obesity prevention strategy?

This study by Melissa Poulson and colleagues is the first study ever to measure how much prenatal and early childhood antibiotic use might contribute to the risk of obesity. Using the rather complete electronic medical records of the Geisinger Health System, Poulson et al examined antibiotic use in 8,793 pairs of mother and child during pregnancy and in the first year of life. The outcome they measured was obesity, measured by BMI z-scores at age 3.

They found no elevated risk of obesity linked to prenatal antibiotic use. But they found a significant increase in obesity risk linked to both antibiotics in the first year of life and to the first three years. This study adds to a growing body of evidence. At this point, the association between antibiotic use and obesity is pretty clear. The authors take it one step further in their conclusion:

By avoiding use of broad-spectrum antibiotics when feasible, limiting repeated antibiotic exposure, eliminating antibiotic use in cases that lack evidence of efficacy, and recognizing the role of cumulative antibiotic exposure in weight gain throughout childhood, this common, population-wide exposure presents a modifiable factor for reducing obesity risk.

At this point, we must remember correlation is not causation. Though the link is clear, cause and effect is not. Professor Diana Thomas offers caution about jumping to conclusions about cause and effect:

The available research shows that infections may influence BMI, and BMI status may influence response to certain infections, as well as to preventive and treatment measures. Perhaps obesity is causing more infections and leading to more antibiotic use. This study cannot resolve the question of cause and effect.

So this important new study raises an important question. Is antibiotic misuse in the first three years of life a modifiable risk for obesity?

It’s a research question worth answering.

Click here for the study by Poulson et al. For an analysis of the relationship between obesity and infections by Thomas and Nikhil Dhurandhar, click here. Finally, you can find more on recent trends in prescribing antibiotics for children here.

Antibiotics, photograph © Michael Mortensen / flickr

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January 28, 2017