Humans are essentially sterile until birth. At birth, every body surface, including the skin, mouth and gut become host to an enormous variety of bacteria. Interestingly, babies pick up bacteria from their mothers and every person and thing that they touch. This means that babies who are born at home are exposed to different bacteria than babies born in hospital. These differences are still measurable months and even years after birth.
Under normal circumstances the bacteria play an important role in maintaining our health. Recent research has shown that they help us digest our food and build our immune system. The highest concentration of microbes in the body live in the gut, where there are over a trillion different microbes from over 500 different species. The scientific term for the ecosystem of microbes that live within the gut is ‘microbiota’.
Along with bacteria, there are also fungi and viruses that live within the gut. Collectively, all of these microbes are known as the ‘microbiome’. There is huge variance between microbiomes even among individuals of the same age and sex. Just like our genes vary, we differ in the type and abundance of each bacteria component. We know that the microbiome between individuals varies between gender, diet, climate, age, occupation, and hygiene.
Often referred to as our second genome, the microbiome represents a new, and still to be fully explored, frontier in human health and medicine.
Just as we are only beginning to understand the key role of bacteria in health, we are also just starting to understand the consequences of disturbances and dysfunctions within the microbiota. Indeed, dysfunction and imbalances of the bacteria that live within the gut have been linked to conditions ranging from inflammatory bowel disease through to obesity and antibiotic-resistant infections.
Scientific studies have shown that bacterial community composition is remarkably altered in these diseases, with healthy people typically exhibiting a stable and diverse community of bacteria when compared to people with disease symptoms.
The relationship between the bacteria that live within the gut and our health stretches further than the gut itself. There is even evidence that links imbalances of bacteria in the gut to conditions like depression and multiple sclerosis.
As imbalances within the microbiome are associated with a variety of diseases, addressing microbial imbalances through medical therapy offers an exciting new treatment avenue for patients.
One such medical therapy called Faecal Microbiota Transplantation (FMT) involves the transfer of bacteria from a healthy person into the bowel of someone suffering from a disease.
FMT has been shown in clinical trials to be a highly successful treatment for patients suffering from recurrent C.diff infection, with cure rates of around 90%. FMT has also shown promise as a treatment for a number of other conditions such as Ulcerative Colitis and Irritable Bowel Syndrome.