Babies who are breastfed that are given antibiotics are more prone to coming down with infections and obesity later on, according to a new study.
Finnish researchers found that children who had received no antibiotics before weaning was associated with fewer uses of antibiotics, as well as decreased body mass index (BMI) later in childhood.
They believe this is the case since a mother’s breast milk contains certain bacteria that help an infant develop helpful intestinal bacteria known as microbiota. But the introduction of antibiotics may blunt microbiota growth, which is essential to the development of an infant’s immune system and metabolism.
The study, published in JAMA Pediatrics, included 226 Finnish children who had participated in a probiotic trial from 2009 to 2010. A questionnaire given to mothers determined which children received breast feeding and antibiotics. About 97% of the children were breastfed for nearly a month, and the average duration was 8 months.
Among 113 children with no antibiotic use before weaning, breastfeeding linked to fewer postweaning antibiotic courses and decreased BMI later in childhood. However, the other children who were given antibiotics were more susceptible to infections and obesity.
“The protective effect of breastfeeding against high [BMI] in later childhood was evident only in the children with no antibiotic use during the breastfeeding period,” the authors wrote. “The results suggest that the metabolic benefits of breastfeeding are largely conveyed by the intestinal microbiota, which is disturbed by antibiotic treatment.”