Potential Link Between Antibiotic Use and Childhood Obesity

A new study conducted at Johns Hopkins Bloomberg School of Public Health in Baltimore, Maryland, suggests that children who receive antibiotic treatment on a regular basis gain weight faster than other children. The findings were reported in the International Journal of Obesity.

As current statistics show that 1 in every 3 children in the US is overweight or obese, the risk of childhood obesity is now topping the laundry list of parental concerns – even out-competing smoking and drug abuse. Childhood obesity numbers have more than tripled from 1971-2011, according to the American Heart Association (AHA), and overweight children are facing serious health complications including type 2 diabetes, high blood pressure and high cholesterol levels.

As early as the discovery of penicillin, researchers have noted that certain byproducts of antibiotic metabolism stimulated weight gain in animals. This finding has led to the current industrial farming practice of adding antibiotics to livestock feed in an effort to bulk them up relatively quickly.

Previous research has also identified a link between antibiotic use early in life and weight gain, however the current study is the first population-based, large-scale study to test the longitudinal effect of consistent antibiotic use on healthy children of a broad age group. Dr. Brian S. Schwartz, a professor in the Department of Environmental Health Sciences at the Bloomberg School, and his colleagues, used the electronic health records of 163,820 kids aged 3 to 18, between the years of 2001 and 2012.

The team used height and weight data to determine each child’s body mass index (BMI), and correlated the BMI with information about antibiotic use. The researchers found that children who were given antibiotics seven or more times during childhood, weighed on average 3 lbs heavier than their unmedicated peers, at age 15.

Alarmingly, the study found that almost 30,000 children – that’s 21% of the children in the study – had been prescribed antibiotics seven or more times during childhood. According to Schwartz, physicians are becoming more mindful in prescribing antibiotics however, parents often demand the drugs, even for illnesses such as cold viruses that cannot be treated using antibiotics

Schwartz said, “Systematic antibiotics should be avoided except when strongly indicated. From everything we are learning, it is more important than ever for physicians to be the gatekeepers and keep their young patients from getting drugs that not only won’t help them but may hurt them in the long run.”

Though the study results are worrying enough on their own, Schwartz believes that the weight gain as a result of frequent antibiotic use could be underestimated in some children. He points out that antibiotics obtained outside the healthcare system, as well as those prescribed during adolescence would not be included in the electronic health record.

“Your BMI may be forever altered by the antibiotics you take as a child,” said Schwartz. “Our data suggest that every time we give an antibiotic to kids, they gain weight faster over time.”

The study authors postulate that that the weight gain could be attributed to loss of beneficial gut bacterial – which help us digest our food – following a course of antibiotics. Once these so-called ‘good bacteria’ are lost, the microflora of the gut could be altered, leading to inefficient digestion and weight gain.

“While the magnitude of the weight increase attributable to antibiotics may be modest by the end of childhood, our finding that the effects are cumulative raises the possibility that these effects continue and are compounded into adulthood,” commented Schwartz.

Sources:

• Are antibiotics making our kids fat? – http://www.medicalnewstoday.com/articles/301423.php
• Schwartz, B., Pollak, J., Baily-Davis, L., Hirsch, A., Cosgrove, S., Nau, C., Kress, A., Glass, T., Bandeen-Roche, K. (2015). Antibiotic use and childhood body mass index trajectory. Journal of Obesity.