Gut Instinct: Methods Of Being Born And Fed Affect The Immune System

Our gut does not only help us in food digestion. It affects almost everything in a human body from mental health and sleep, to cravings for certain foods and weight gain. Earlier it was believed that foetuses had no presence of bacteria in their gastrointestinal tract but then it was observed that the babies begin to accumulate microbes while being born.

It is clear that new born babies have minimum, if any, diversity in the collection of bacteria that accumulates in their gut, known as microbiota. This collection becomes much more diverse as the child is exposed to different environments and surroundings. A new born baby's gut microbes are of importance because they have been shown to affect the risk of development of certain diseases in the baby's childhood or adulthood, according to IFL Science.

How a baby is born, has a remarkable impact on his gut microbes. During vaginal delivery, there is a direct contact with the mother's vaginal and intestinal flora which helps in shaping up a newborn's gut bacteria colonization. However, newborns that are born via caesarean section do not have such a direct contact.

Various studies have been done previously in order to establish a relationship between the mode of delivery and accumulation of gut microbiota. One of those studies has shown that newborns delivered vaginally had colonies of lactobacillus while those delivered via caesarean section were colonized by a mixture of bacteria, such as Acinetobacter and Staphylococcus that are typically found on skin and in the hospitals.

These differences tend to sustain throughout the life. However, the impact these early differences have on a child's health and the association with risk of disease is still unknown.  

Gut bacteria plays a vital role in the growth of an infant's immune system. Altering the development of white blood cells in the immune system could help in achieving the maximum level of disease protection as these white blood cells are responsible for defense against invading microbes that make a person sick.

Researchers found that mice born in a germ-free environment were more prone to bacterial infection since they had lesser number of white blood cells as compared to healthy mice with normal population of gut bacteria. Children born via caesarean sections are at a higher risk of encountering asthma and hay fever. They are also more likely to be hospitalized for acute gastroenteritis.

Although newborns delivered via caesarean section are more likely to fall sick, it is important to note that all caesarean section cases are not the same. Sometimes women deliver babies via caesarean section after a long period of labour where her waters have broken. In such a case, the baby would be exposed to a much different microbial environment than a planned caesarean section carried out while the waters are still in place.

Also, breast-fed babies have higher proportions of the beneficial species of bacteria, Bifidiobacterium, than babies who are formula-fed. Breast milk can promote a healthy crosstalk between the newborn's immune system and gut microbiome.