The study results showed that breastfeeding beyond three months supports the gradual maturation of the microbiome in the infant’s digestive system and nasal cavity the upper part of the respiratory tract. Conversely stopping breastfeeding earlier than three months disrupts the paced development of the microbiome and was linked to a higher risk of preschool asthma.

Some components in breast milk such as complex sugars called human milk oligosaccharides can only be broken down with the help of certain microbes. This provides a competitive advantage to microbes capable of digesting these sugars. By contrast infants who are weaned earlier than three months from breast milk and who then rely solely on formula feeding become home to a different set of microbes ones that will help the infant to digest the components in formula. While many of these microbes that thrive on formula do eventually end up in all babies the researchers showed that their early arrival is linked to an increased risk of asthma.

Just as a pacemaker regulates the rhythm of the heart breastfeeding and human milk set the pace and sequence for microbial colonization in the infant’s gut and nasal cavity ensuring that this process occurs in an orderly and timely manner said study co-senior investigator and computational biologist Liat Shenhav PhD.Healthy microbiome development is not only about having the right microbes. They also need to arrive in the right order at the right time said Dr. Shenhav an assistant professor at NYU Grossman School of Medicine its Institute for Systems Genetics and the school’s Department of Microbiology.

The data provided by the CHILD Cohort Study enabled researchers to detangle the impact of breastfeeding on an infant’s microbiome from a range of other environmental factors including prenatal smoke exposure antibiotics and the mother’s asthma history.

Even when these factors were accounted for they found that breastfeeding duration remained a powerful determinant for the child’s microbial makeup over time. They also used these microbial dynamics and data on milk components to train a machine learning model that accurately predicted asthma years in advance. Finally they created a statistical model to learn causal relationships which showed that the primary way breastfeeding reduces asthma risk is through shaping the infant’s microbiome.

Our research highlights the profound impact of breastfeeding on the infant microbiome and breastfeeding’s essential role in supporting respiratory health. By uncovering the mechanisms behind the protective effects of breast milk as demonstrated in this study we aim to inform national guidelines on breastfeeding and weaning from breast milk in a data-driven manner.

Source: https://nyulangone.org/news/breastfeeding-crucial-shaping-infants-microbes-promoting-lung-health