Breastfeeding can 'protect infants from antibiotic-resistant bacteria'

Breastfeeding your newborn can protect them from bacteria that are resistant to antibiotics, according to a new study.

Research carried out at the University of Helsinki found that infant formula, which acts as a substitute for breastmilk, was associated with a roughly 70 per cent higher occurrence of antibiotic-resistant genes in the infant gut, more than the other factors studied.

The study, which reanalysed gut microbiota data of more than 600 newborns from previous research, also demonstrated that breastfeeding newborns was associated with a reduced proliferation of opportunistic pathogens resistant to antibiotics in the infant, which may lessen the risk of difficult infections.

According to the researchers, a considerably higher abundance of resistance genes was seen in children whose diet consisted at least partially of infant formula compared to children who were exclusively breastfed or consumed donated breastmilk.

However, infant fortifier based on cow's milk, which is routinely used to improve the diet of breastfed infants, did not have any perceptible effect on the number of resistance genes. The effect of infant formula exposure was also markedly more significant than that of antibiotic regimens given to the mother or infant.

The increasing prevalence of bacteria resistant to antibiotics constitutes a significant risk to human health but is most often thought to result from abundant antibiotic use, as exposure to antimicrobial drugs promotes the enrichment of microbes that are resistant to them.

However, Dr. Katariina Pärnänen, who conducted the research as part of her doctoral thesis, said that breastfeeding can also help as it reduces these antibiotic-resistant bacteria in newborns.

"Breastmilk is the primary source of nutrition for all infants, and its health benefits are of particular importance to premature infants," she said. "The new findings indicate that breastfeeding premature and newborn infants also reduces the proliferation of bacteria resistant to antibiotics in the infant gut, thus potentially reducing the risk of difficult infections, which I consider a particularly important find due to the ever-increasing prevalence of antibiotic resistance."