MICROBIOME: Does It Control Everything?
Researchers now estimate that a typical human body is made up of about 30 trillion human cells and 39 trillion bacteria.
These are key in harvesting energy from our food, regulating our immune function, and keeping the lining of our gut healthy.
Interest in, and knowledge about, the microbiota has recently exploded as we now recognise just how essential they are to our health.
A healthy, balanced microbiome helps us break down foods, protects us from infection, trains our immune system and manufactures vitamins, such as K and B12.
It also sends signals to our brain that can affect mood, anxiety and appetite.
Imbalances in the gut are increasingly being linked to a range of conditions. Last year, scientists at California Institute of Technology found the first ever link between the gut and Parkinson's symptoms.
The composition of our gut microbiota is partly determined by our genes but can also be influenced by lifestyle factors such as our diet, alcohol intake and exercise, as well as medications.