The microbiome is the trillions of microorganisms (also called microbes or microbiota) of thousands of different species that live over and inside the surfaces of our body, like a ‘living’ paint, which at a microscopic scale, is teeming with life. These living microorganisms include not only bacteria, but also fungi, parasites, and viruses. 

The largest concentrations of microbes are found in our gut, particularly in our large intestine (although there is growing evidence these microbe populations are everywhere, including the lung and even the brain). Since 2007, when the massive human microbiome project was first launched, research has exploded and we have discovered that these microorganisms (the number of them, types of different ‘bugs’ and the interplay between them) all have a profound effect on our health. In a way, our microbiome could be said to be the most important ‘organ’ in our body.

The organisms in the microbiome can be either helpful or potentially harmful, and even those deemed harmful can react differently in different environments, meaning there is still a lot to learn! Most microbes are symbiotic (both they and our human body benefit from them being there), but some have been identified as being pathogenic (damaging or causing disease). 

These gut microorganisms can produce chemical signals and proteins that interact with our immune system (80% of which live in our gut), our enteric nervous system (a vast nerve network, which connects directly to our brain, via the vagus nerve) and also our gut wall, either improving our health, or creating ‘leaky gut’

Many of our gut villains can disrupt the healthy microbiome balance and when this disruption is severe and prolonged, we call it dysbiosis. Dysbiosis is thought to be a root cause of many chronic diseases, mental illness, inflammation and multiple health symptoms.