The collection of bacteria residing mainly in our gut – known as the human microbiome – is of huge significance to our health and wellbeing. Many studies have demonstrated how changes to the make up of the bacteria and microbes in our microbiome have been linked with a huge range of health issues and diseases – ranging from digestive disorders and food allergies, to skin problems, metal health disorders, obesity, diabetes and metabolic conditions, to a range of auto immune diseases such as parkinsons and MS.
Numerous studies have shown how the way in which we are born and fed in infancy can affect the development of our microbiome and also our predisposition to these conditions and diseases in later life. However scientists are still years away from understanding what the different bacteria in our microbiome do for us, both individually and collectively.
Now in a study published in msphere, scientists have shown how they can influence and even change the make up of the microbiome in babies when they were breastfeeding by giving them a certain strain of bacteria for a month.
Babies are particularly vulnerable from disease and infection in infancy and the development of their microbiome in early life is understood to be important to their health and i ensuring the correct function of their metabolic and immune system. Before birth babies are believed to be largely sterile of bacteria – and so their passage through the birth canal provides an important introduction of friendly bacteria to lay the foundations of their microbiome. The subsequent milk they receive through breast feeding continues to provide a rich source of the right friendly strains of bacteria – allowing these bacteria to colonise effectively and establish a strong presence.
Doctors and Scientists now know that factors such as cesarean section birth delivery, the use of antibiotics at or following birth, and formula feeding all result in significant changes to the development and make up of the infants microbiome and put them at a higher risk of contracting certain diseases later in life.
However with such a huge number of bacteria and species – with a make up that is unique to each of us – researchers are still struggling to understand what exactly a normal microbiome looks like.
This new study set out to establish whether it was possible to change the make up of the microbiome of a baby in infancy.
Researchers gave new born babies a subspecies of Bifidobacterium longum – a common commensal (or friendly) strain of bacteria for three weeks. They analysed the babies poo for the next six months to understand if this species would actually able to colonize and establish itself in the gut. At the end of six months after the treatment they found this subspecies were still present in significant numbers.
The findings could pave the way to shape the development of the microbiome and help prevent such diseases in later life.
As part of the study, the researchers investigated two groups of infants; One group born through normal vaginal birth and the second group born through cesarean section, which is known to disrupt an infant’s microbiome. The researchers noted that the bacterial colonies in the two groups were different at the start of the study – but that after they were all given the same bacterial strain, the group born via cesarean section developed microbiomes that more closely resembled vaginally-delivered newborns. “The probiotic was able to eliminate the differences inherent to c-section delivery,” said Mark Underwood, a neonatologist at the University of California, who was behind the study.
Mark Underwood, a neonatologist at the University of California, who was behind the study said: “We hypothesize that this will have a long-term impact on the immune system, even decades later ‘However he explains “this isn’t what usually happens in adults, but infants have gut microbiomes and diets that are much simpler, making them easier to manipulate.
Still the findings are exciting as the raise the possibility of treating infants at risk of developing unhealthy microbiomes and associated conditions and diseases.
However, while the results are exciting, we just don’t know much of an influence these changes in an infants gut microbiome has on the risk of the development of disease. While these changes and adjustments to the make up of the microbiome could have a long-term impact it will take many decades to know for certain.
There will need to be many of these long-term comparative studies to truly understand what constitutes a healthy or unhealthy microbiome, and how much the birth factors – such as cesarean section and being formula fed harms the development of our microbiome.