Nourishy Blog Gut Microbiome

Breastmilk is truly remarkable. Did you know that within our intestines, we harbour an ecosystem of 100 trillion or more living microorganisms, including bacteria, viruses, and fungi? These microorganisms play crucial roles such as breaking down food, synthesising vitamins, and defending against pathogens. This ecosystem is known as our intestinal microbiome. So, what does this have to do with breastfeeding? Well, breastfeeding is key to establishing a healthy microbiome in our babies, which has long-lasting effects on their overall health.

Breastmilk is a complex mixture of nutrients that are unique to each mother and baby. This incredible milk also contains beneficial bacteria and prebiotics. Nursing directly from the breast enhances the transfer of these beneficial organisms, as the baby is exposed to bacteria from the mother's skin around the areola.

The health benefits of a healthy microbiome begin in the first three years of life and continue throughout one's lifespan. Breastmilk helps to seed and nurture the microbiome with beneficial bacteria until the baby's gut is fully developed. These beneficial gut bacteria play a crucial role in reducing the risk of chronic diseases like asthma, obesity, allergies, inflammatory bowel disease, and neurodevelopmental disorders. They also contribute to regulating mood, cognition, and pain through the brain-gut axis.

While breastfeeding is a major factor in shaping a baby's microbiome, other factors also influence it, such as the method of birth (vaginal or caesarean), the mother's microbiome and BMI during pregnancy and lactation, gestational age at birth, maternal stress levels, antibiotic use, duration of breastfeeding, introduction of complementary foods, presence of siblings, maternal diet while breastfeeding, milk composition at different stages of lactation, and even the presence of pets in the home.

Regardless of these factors, the overwhelming evidence shows that breastmilk is incredibly beneficial, whether provided for a short or long duration. Even if the baby does not nurse directly from the breast, breastmilk still offers numerous health benefits. Research has shown that breastfed newborns have a more stable and uniform population of microorganisms compared to formula-fed babies. Even small amounts of formula can lead to shifts in the microbiota composition.

The type of feeding a baby receives in the early months of life appears to be a crucial determinant of their well-being in childhood and adulthood. The protective effects of breastfeeding seem to stem from its ability to modulate the composition of intestinal microflora in the early stages of life.

Breastfeeding and the Microbiome | OHSU. (n.d.). Www.ohsu.edu. https://www.ohsu.edu/school-of-medicine/moore-institute/breastfeeding-and-microbiome#:~:text=Breastmilk%20seeds%20and%20nurtures%20the
‌ Breastfeeding, bacteria and your baby’s gut | Australian Breastfeeding Association. (n.d.). www.breastfeeding.asn.au. https://www.breastfeeding.asn.au/resources/breastfeeding-bacteria-and-your-babys-gut
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