Antibiotic Exposure Does Not Lead to Obesity: True or False?

Studies in mice show that exposure to antibiotics affects the gut microbiome, alters metabolism, and results in increased adiposity. In addition, observational studies have suggested an association between antibiotic exposure and obesity in children. To assess the association between early antibiotic exposure and weight gain during a child's first 8 years of life, researchers reviewed records of children born between 2001 and 2011 (≥35 weeks gestation; weight ≥2000 g) in a network of 30 mid-Atlantic pediatric practices.

Of 38,522 children, 14% were exposed to antibiotics in the first 6 months of life (mean age, 4.3 months) and 67% were exposed by 24 months (52% received broad-spectrum antibiotics, 19% macrolides). In regression analysis, exp…