In the intricate dance between body and mind, the gut has emerged as an unusually powerful choreographer.
My ‘gut feel’ is that we are truly in the infancy of our understanding of this interplay, but research increasingly points to the important role of our gut–brain axis in overall health and wellbeing. It doesn’t just improve digestive and nutritional health. It plays a very direct role in our mental and neurological health.
“The stomach is more intelligent than the brain. It informs you when it’s empty. The brain does not!”
The gut–brain axis directly links the galaxy of neurons in your brain with the trillions of microbial companions in your digestive tract. They communicate through nerves like the vagus nerve, as well as via immune signals and microbial metabolites.
These intricate microbial colonies can directly influence where and how the brain spends its energy and focus and can help provide many neuroprotective molecules, but they can also contribute to neurological decline and brain fog.
Over the past decade, our natural human curiosity around this complex interaction has created quite a buzz, with the subject becoming a bit of an obsession for many. Research has exploded, with studies consistently showing that gut dysbiosis—an imbalance in the microbiome—correlates with a wide range of mental health challenges.
For instance, inflammation triggered by gut irritation can send distress signals to the central nervous system, exacerbating mood disorders such as depression, anxiety, and bipolar disorder, and worsening brain fog.
Clinical trials have shown that eating more fermented foods and including a greater diversity of fibre in our diet can measurably improve symptoms of anxiety disorders and mild to moderate depression, show promise for ADHD symptoms, and even support the management of bipolar disorder.
One intriguing area is schizophrenia, where promising early animal and small human studies are exploring how changing the microbiome—including through faecal microbiota transplants—might one day complement existing treatments.
“All disease begins in the gut.” — Hippocrates (~400 BCE)
Our neurological health is equally dependent on a healthy gut. The connections between gut health and neurodegenerative disorders such as Parkinson’s, Lewy body dementia, vascular dementia, and Alzheimer’s disease are increasingly taking centre stage. Several studies link gut dysbiosis with progression from mild cognitive impairment to dementia.
In a substantial percentage of people with Parkinson’s, there seems to be a ‘gut-first’ trajectory, where gastrointestinal changes and alpha-synuclein build-up in the gut appear years before motor symptoms.
The beta-amyloid plaque and tau tangles associated with Alzheimer’s also have a compelling gut dysbiosis origin story.
Research, including preclinical and human observational studies, indicates that increasing fermented food intake and dietary fibre diversity offers significant benefits in managing Parkinson’s symptoms, reducing the progression of Alzheimer’s, and supporting overall neurological health.
Healthy Gut, Healthy Brain
A thriving gut microbiome produces neuroprotective metabolites in far greater variety and abundance than previously suspected. These include a variety of short-chain fatty acids, neurotransmitters, indole derivatives, secondary bile acids, branched-chain amino acids, GLP-1, polyphenol-derived compounds, and so much more.
These compounds help reduce neuroinflammation, support neuronal survival, modulate oxidative stress, preserve the blood-brain barrier, promote neurogenesis, and slow the progression of neurodegenerative conditions.
For these reasons and more, it is imperative to look after your gut and its mind-blowingly complicated microbial ecosystem.