Breastfeeding mums' diet may affect children's asthma risk

A new preclinical study, led by QIMR Berghofer Medical Research Institute, has demonstrated that a high-fibre diet in breastfeeding mothers helped to reduce the risk of infants developing severe lower respiratory infections (sLRIs), which can predispose the infant to chronic lung diseases such as asthma.

Senior researcher Associate Professor Simon Phipps said the study’s findings were significant because they suggested a mother’s diet affects the quality of her breastmilk, which is key to triggering a baby’s immune resistance to sLRIs. The early results, published in the journal Immunity, could lead to improved guidance for breastfeeding mothers, along with efforts to modify baby formula to have a similar protective effect.

“Poor maternal diet increases the incidence of severe lower respiratory infections, such as pneumonia and bronchiolitis, in an infant,” Phipps said. “These infections are a major cause of infant morbidity worldwide, and increase childhood asthma risk.

“In preclinical models, we found that dietary fibre affects the composition of the mother’s milk microbiota, which in turn affects the development of the infant’s gut microbiota.

“When a breastfeeding mother eats a high-fibre diet, her healthy milk microbiota kicks off a process that promotes the development of an important population of immune cells. We have identified that the microbes talk to the cells that line the gut, and these cells then produce a growth factor that supports the immune cells in the bone marrow. These immune cells then protect the infant against severe lower respiratory infections.

“A low-fibre maternal diet disrupts this process of immune development.”

The study forms part of the ongoing effort by Phipps’s laboratory to understand the mechanisms linking maternal diet, breastfeeding and the microbiome to neonatal immune development and protection against acute and chronic diseases. He said the findings suggest researchers may be able to prevent asthma if they can identify the healthy breastmilk microbes that trigger an infant’s immune resistance to sLRIs.

“Our data indicates that if we can promote a healthy gut in the very young, we will prevent asthma and various other chronic inflammatory diseases,” he said.

“However, the research still has a very long way to go. We are presently examining human milk to identify the microbes that confer protection against a severe lower respiratory infection and to confirm that the same molecular processes are involved.

“The end result could be a targeted probiotic, which may be provided to all infants, and in particular those who are being fed baby formula, to ensure optimal development of the infant’s immune system and to lower the incidence of various diseases.”

Image credit: iStock.com/Anastasiia Stiahailo