The Gut Microbiome

In the last decade, exciting advances in medical technology have meant that we can now easily sequence the gut microbiome. The research has followed rapidly, however we are only at the tip of the iceberg in our understanding of this fascinating field.

So what is the gut microbiome and why is it important?

Microbiome refers to a community of micoorganisms (including bacteria, viruses, fungi) that inhabit the human body. Therefore the gut microbiome refers to organisms that inhabit the gastrointestinal tract.

There are more than 100 trillion organisms that inhabit the human body. In fact there is more bacterial DNA in the human body than human DNA!

A large number of the microorganisms inhabit the gastrointestinal tract with the highest percentage being in the large intestine. Analysing a stool sample gives us a peek into the large intestine’s microbiome and this is where the research gets fascinating.

With the use of DNA sequencing techniques, called metagenomic sequencing, all the genes of the organisms in the stool sample can be assessed and from this the functional potential of the organisms, even if they have never been identified before. So not only are we learning about the metabolites that certain organisms can produce, but also the potential to impact our health and well being in both positive and negative ways.

The Importance of the Gut Microbiome

As the research advances at a rapid pace, we are only just beginning to unravel the effect of the gut microbiome on our health. Currently there is evidence to support the following links between gut health and certain disease states:

1. Inflammatory bowel disease

Diseases such as Crohn’s Disease, Ulcerative Colitis, colorectal cancer and even Irritable Bowel Syndrome are associated with altered microbial diversity and presence or absence of specific organisms.

2. Diabetes Type 2

Studies have revealed that glucose metabolism is affected by gut bacteria. Interestingly a common diabetes medication called Metformin achieves its regulation of glucose by changes in the gut microbiota!

3. Anxiety and Depression

It appears that the gut-brain connection is bidirectional with gut microbes producing various neurotransmitters and metabolites that can act directly on the brain via the Vagus nerve or interact with the immune system, which then communicates with the brain. It’s fascinating to think that the brain then works directly on the gut, altering the microbial makeup in response to these signals.

4. Cardiovascular Disease

Various metabolites produced by gut organisms have been shown to be associated with increased risk of developing atherosclerotic plaques, even if there are no other risk factors for cardiovascular disease.

5. Neurodegenerative Disorders

Alzheimer’s Disease, Parkinson’s’ Disease and Multiple Sclerosis patients have been shown to have an altered microbial composition compared to healthy individuals. There is a direct link with inflammatory metabolites produced by gut microorganisms and the response of certain immune cells of the central nervous system such as microglia. Although this may sound concerning, the good news is that research is also showing that certain metabolites can act directly on microglia to prevent inflammation.

This is an exciting time in the evaluation of the gut microbiome and the links to our health and well being. There is much yet that we still don’t understand but as DNA sequencing technology becomes widespread and affordable, revolutionary new approaches to traditional disease management and even novel strategies for prevention of disease are just on the horizon. Stay tuned!

You can book and appointment with Dr Lyn Tendek at Next Practice Sydney appointment page or read more about Lyn here.