breastfeeding is essential to the formation of the intestinal microbiota

Breastfeeding is essential to constituting a newborn’s intestinal microbiota, confirms a new study published in the journal Jama Pediatrics.


A baby’s intestinal microbiota develops over the course of the first months of its life: the child’s health depends on the quality of its microbiota and its ability to defend itself against diseases. We know that breastfed individuals’ intestinal flora has a different composition than that of bottle-fed individuals, even when they are adults.

To determine in what proportions bacteria from the mother are transferred to the child during breastfeeding, American researchers studied 107 mother-child pairs for a year. They tracked the bacterial composition of the breast milk, cutaneous microbiota from the area of the mother’s areola, and the babies’ intestinal microbiota.

In the first months of life, up to 40% of the bacteria in the intestinal microbiota of breastfed children comes from the mother’s milk and skin. Conversely, the introduction of solid food before six months leads to the premature evolution of the microbiota. Furthermore, bacterial diversity depends on the quantity of milk drunk, even after the introduction of solid food. This observation supports the WHO recommendations for mothers to breastfeed exclusively until 6 months of age, and to continue doing so as a supplement to solid food until 12 months of age, the authors conclude.


Pia S. Pannaraj et al. Association Between Breast Milk Bacterial Communities and Establishment and Development of the Infant Gut Microbiome. Jama Pediatr. Published online May 8, 2017. doi:10.1001/jamapediatrics.2017.0378