The study found that administration of three or more courses of antibiotics before children reach an age of 2 years is associated with an increased risk of early childhood obesity.
Antibiotics have been used to promote weight gain in livestock for several decades, and our research confirms that antibiotics have the same effect in humans, said Researcher Frank Irving Scott, adding that the results do not imply that antibiotics should not be used when necessary, but rather encourage both physicians and parents to think twice about antibiotic usage in infants in the absence of well-established indications.
The researchers performed a large population-representative cohort study in the United Kingdom to assess the association between antibiotic exposure before age 2 years and obesity at age 4 years.
Children with antibiotic exposure had a 1.2 percent absolute and 25 percent relative increase in the risk of early childhood obesity. Risk is strongest when considering repeat exposures to antibiotics, particularly with three or more courses.
"Our work supports the theory that antibiotics may progressively alter the composition and function of the gut microbiome, thereby predisposing children to obesity as is seen in livestock and animal models," added Dr. Scott.
