You may have you heard about the gut-brain connection, or heard the gut being referred to as our ‘second brain’. But what if I were to tell you that you could fundamentally change your mental health and how you feel, by treating your gut? 

Sounds “out there”, doesn’t it...

But if you’ve ever “followed your gut”,

had “butterflies” in your tummy from excitement,

or a “knot” in the pit of your stomach when you’ve been worried,

a “gut-wrenching” experience,

“lost your appetite”,

found yourself “hangry”  (being a moody-chops because you haven’t eaten in a while),

or had the proverbial “s**ts” with something;

then you’ve experienced the gut-brain connection first-hand, and can probably conceptualise how inextricably linked our gut, mood, and emotions are.

It may come as little surprise to you, that anxiety and other mood and mental health disorders can be directly linked to poor gut health...

Whilst gut health has always been at the core of Naturopathic philosophy and treatment (we’re talking in the realm of a couple-thousand years, since Hippocrates ‘The Father of Modern Medicine’ time). It is only in more recent times that we are seeing both a huge shift in paradigms and awareness; with more promising research on the gut-brain relationship emerging, the idea is coming into a space of more understanding and general acceptance. There are now even bestseller books based solely on gut health at the local book store! It’s wonderful to be able to discuss the relevance of the gut and how it is linked to mood, skin, autoimmune disorders and more -and suddenly it’s actually kinda plausible; not just some crazy thing you might hear about in a Naturopathic consultation...

Did you know that you are about 90% bacteria?! I’m not kidding...And the make-up, or balance, of this bacteria (our personal “ecosystem”) can impact not only our gut, digestion, and immune system function; but can also profoundly impact our mental health and emotional wellbeing.

There is a rapidly expanding body of research showing that specific strains of bacteria are indeed influencing our brain. They are actually termed ‘psychobiotics’, because their actions are not dissimilar to that of psychiatric pharmaceutical drugs (like common anti-anxiety drugs that work by targeting GABA receptors). These bacterial strains have been observed toinfluence our emotions, higher cognitive functions, ‘intuitive’ (perhaps quite literally, “from the gut”!) decision-making and motivation. In studies on both mice andhealthy human volunteers, using an array of brain-scanning and psychological tests, psychobiotics are having distinguishable effects.

One study on mice of calm vs. anxious highlighted the psychiatric possibilities of modulating gut flora when faecal microbiota was transplanted from an anxious strain of mice caused a previously calm mouse to behave very anxiously. And, yep, you guessed it... A transplant of gut content from the calm strain had a relaxing (and even confidence-boosting) effect on the anxious strain.

Our mircobiome is influenced by factors like how we were born (vaginal vs c-section), if we were breastfed or bottlefed, our diet or stress levels, metabolism, medications -especially antibiotics, age, geography, and genetics. Whilst there is much more to learn, especially on the exact mechanisms of action; what we are understanding is their ability to modulate our brain chemistry. With a serious percentage of neurotransmitter (NT) production and receptor sites residing in the gut (40 NTs in the gut have been identified, to date), it makes sense that if the ecology of our gut is out, our mental and emotional wellbeing is going to follow (and vice versa).

But our mental health and emotional wellbeing is not just governed by the health status of our microbiome. It is also profoundly influenced by an orchestra of nervous system data, endocrine, inflammatory and immune messengers...

The gut pretty much has an entire nervous system cosmos of its own. This is the Enteric nervous system, which is embedded in the gastrointestinal lining, and also referred to as the “second brain”. The Enteric nervous system contains an estimated 500 million neurons -yup; and it is thought to house more neural tissue than that the spinal cord or the peripheral nervous system (everything outside of the brain and spinal cord!).This means there is a veritable information superhighway in there; that is constantly sending, receiving and reacting to various neural and chemical signals!  Some of these messengers that traverse it include:

●      Stress hormones such as Adrenalin, Noradrenalin, Cortisol

●      Metabolites including toxic materials produced by the microbiome -which, Sarkis Mazmanian, a Medical Microbiologist and Professor at the California Institute of Technology, says function as “equally drug-like chemicals” in their communication with the brain.These metabolic molecules have a demonstrated ability to cause behavioral abnormalities in mice that are associated withanxiety (and even autism) when otherwise healthy mice are inoculated with them.

●      Inflammatory cytokines: messengers of inflammation

●      Serotonin: the happy, calming, feel-good NT (95% of which is produced in the gut, meaning only 5% is made in the brain)

●      GABA: the chillaxing NT (significant amounts of GABA are synthesised by the bacteria species Lactobacillus and Bifidobacterium, which are known to inhabit the gut);

●      Dopamine: the pleasure and motivation NT (about 50% produced by the enteric nervous system in the gut)


“Stress” can be experienced on different levels (mental, emotional, physical), and originate from various sources (e.g. nutritional, chemical, psycho-social, environmental, visceral). Now, consider how extensive this nerve plexus in our bellies I’m talking about is; and how positively connected this neural superhighway is to our brain... This (enteric) nervous system, and the vagus nerve are highly attuned to our thoughts, moods, emotions, and of course, stress response. In fact, stress signals release neurotransmitters and proinflammatory cytokines, affecting the gut in a number of ways, one of which being the initiation of an inflammatory cascade, which compromises intestinal integrity; contributing to ‘leaky gut’ issues.

Some studies have demonstrated how bacterium exposed to noradrenaline (a stress hormone) clearly responded to stress, and may even induce stress, as a heightened perception of stress or anxiety-like behaviour has been demonstrated.

So, whilst the ‘beneficial’ bacteria are associated with more positive mood and mental health states, greater nerve plasticity and repair; the pathogenic bacteria appear to have the opposite effect.

As you can see, a crucial part of treating anxiety, and other mood and mental health disorders (even more serious disorders such as bi-polar and schizophrenia) actually lies within addressing the gut.


The basis of Naturopathic treatment uses the tenets of ‘Nutritional Psychiatry’ (that is, a nutritional medicine approach to prevention and treatment of mental disorders) to restore mental (emotional and behavioural) wellbeing.

From a Naturopathic standpoint, it is always important to work holistically. So one would also consider the regulation of these pathways through not only the modulation of the microbiome inhabiting the system; but also the repair the intestinal lining to resolve any pervasive“leaky” gut issues. The latter being where toxic metabolites may be escaping into the bloodstream causing a cascade of chemical messengers to ensue. This inflames the system and the brain; which is a mechanism shown to cause, drive, and exacerbate mood and mental health disorders.

The power of a few significant dietary and lifestyle changes are utilised; avoiding those things we understand have a negative impact on our gut, microbiotica, and mood -such as: processed, fried, and sugary stuff.  And getting stuck into real, whole foods; fresh, from the source, non-adulterated, that grows in the ground, on trees, in your garden, or hails from a farm, and are recognisable as foods (wild-caught fish, organic, grass-fed meat, free range eggs, legumes, leafy greens, and an array of fresh, seasonal fruit and veg for example), rather than packaged goods. Along with specific, individualised supplementation to replete and balance the system, where necessary.


The Journal of Neurogastroenterology and Motility reported the probiotic Bifidobacterium longum NCC3001 normalised anxiety-like behavior in mice with infectious colitis by modulating the vagal pathways within the gut-brain. The gut-brain connection is actually via the vagus nerve, which acts as a direct neuronal higway between our gut, brain and organs.

Craniosacral therapy can work to activate and “tone” the vagus nerve. This downregulates the sympathetic stress response in the body, and promotes your natural relaxation response, elevating feelings of calm and stability, and decreasing inflammatory mediators.

As your vagus nerve is activated, you are reassociated with what it feels like to be at ease. It stimulates the release of oxytocin (aka the “hug” or “bliss” hormone), and has a myriad of other benefits on the gut, digestion, organs and wellbeing.


If you would like to make a Naturopathy or Craniosacral therapy appointment, you can book online

Shanna is a qualified Naturopath and EFT Practitioner, and member of the Australian Natural Therapists Association (ANTA). 

Shanna's interest in natural medicine came about through her own health challenges. She has a special interest in helping people with natural fertility, hormone balance, stressanxietydepression, fatigue and general wellbeing. 

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