Mothers considering the merits of formula vs. breast milk have mostly weighed nutritional qualities, which are similar though not identical. Babies fed formula miss out on the immunological protection available through breast milk (Nutrients, May 11, 2016). Now scientists have found another reason to feed newborns breast milk if at all possible: bacteria with antibiotic resistance.
Antibiotic-Resistant Bacteria in Babies Fed Formula:
Bacteria that do not respond to antibiotics are especially dangerous for newborn babies. Doctors have long blamed antibiotics administered early in life for encouraging antibiotic resistance.
A new study suggests, however, that formula feeding may also contribute to greater numbers of antibiotic resistant bacteria (American Journal of Clinical Nutrition, online Oct. 22. 2021). The scientists studied the genomes of gut bacteria in 46 neonates. Babies fed formula instead of breast milk had more bacteria considered potentially pathogenic. In addition, these bacteria had 69 percent more antibiotic resistance genes. Overall, breastfed infants had more Bifidobacteria and other beneficial types of bacteria than infants getting formula.
Pediatricians have known for a long time that breastfeeding promotes more microbial diversity for little babies. Nearly five years ago, we were fascinated to read such a study.
Breastfeeding Helps Babies Get the Right Bacteria in Place:
The scientists examined microbial samples from more than 100 pairs of mother and infants (Pannaraj et al, JAMA Pediatrics, July 2017 ). They found that important microbes in the babies’ stool matched bacteria in their mothers’ milk and on their mothers’ skin.
The milk microbes that colonized the infants’ digestive tracts were associated with more diverse microbial communities. This is how breastfeeding gives them a good start, presumably making for better digestive health both in infancy and at later ages.
In response to this report, Ellie posed an interesting question:
“For years, low income and minority women have not breastfed their babies while educated women have embraced breast feeding. At the same time, obesity has grown in the lower income, minority population. Is anyone doing a study on beneficial bacterial derived from breast feeding and non-breastfed lower income children?”
So far as we know, that particular question has not been answered through research. Lack of maternity leave or breaks to pump breast milk makes it far more difficult for low income women to establish or continue breast feeding.
You can learn more about the importance of diversity in the gut microbiome, not for babies but for adults, from our interview with Dr. Robynne Chutkan, author of The Microbiome Solution.
