Key facts
- What it is: two-way communication between gut microbes and the brain.
- Channels: the vagus nerve, microbial metabolites, immune and hormonal signalling.
- GI-MAP's role: profiles the gut microbiome relevant to the axis; it does not diagnose mood or neurological conditions.
- Status: an active, emerging area of science.
The gut-brain axis is the two-way communication network between the gut, its microbes, and the brain. Research increasingly describes a distinct microbiota-gut-brain axis, in which the trillions of microbes in the gut influence — and are influenced by — the nervous system. A comprehensive stool test like the GI-MAP (Gastrointestinal Microbial Assay Plus) profiles the microbiome that sits at the centre of this axis.
What the science says
A comprehensive review of the microbiota-gut-brain axis describes how gut microbes communicate with the brain through multiple routes — the vagus nerve, microbial metabolites, immune signalling and gut hormones — and how this axis is being studied in relation to stress, mood and behaviour (PMID: 31460832).
This is a fast-moving research field. The associations are real and important, but they do not mean a stool test can diagnose or treat a mood or neurological condition.
How testing fits in
Because the axis begins with the microbiome, some people and practitioners use a comprehensive stool profile to understand the beneficial flora, dysbiosis and gut-function markers that research links to gut-brain communication. Any findings are educational inputs, interpreted with a qualified practitioner, and are not a substitute for mental-health care.
The GI-MAP™ reports this and 85+ other markers from one at-home sample.
Order Your GI-MAP™ Test → See pricingReferences
- Cryan JF, O’Riordan KJ, Cowan CSM, et al. The microbiota-gut-brain axis. Physiol Rev. 2019;99(4):1877–2013. PMID: 31460832.