Gut health for mental health

How do I improve gut health for mental health?

Registered Nutritionist Ceri Ball delves into the science behind the gut-microbiota-brain axis.
Caitlin Hall
by Ceri Ball
BSc qualified Nutritionist (BANT) specialising in Women’s health, Gastrointestinal Health, Mood, Energy Support and Weight Management.

Both mental health and gut health seem to be much-talked about health topics, and although there is still much to discover within the realm of nutrition psychiatry, it is an extremely exciting unfolding. But how exactly are the gut and brain linked? More importantly, how can we improve gut health for mental health?

What is the gut-brain axis?

A concept that many have heard is ‘Mood Food’ which describes how the food we eat affects our mood. Our gut-microbiota-brain connection plays a key role in this exchange.

Over the last decade or so, this fascinating connection has acquired an important position in science. The gut-microbiota-brain axis is a dynamic matrix of tissues and organs, including the brain, glands, immune cells, and of course, the gut microbiota – consisting of a huge family of bacteria, fungi and archaea that live throughout our gastrointestinal tract. 

Communication between the gut- brain-axis (GBA) is a complex bidirectional affair via the wondrous vagus nerve, which is the longest and most widely distributed nerve within the body; think of it as the telephone line between the GBA, which comprises a vast neuronal network found within the gut which enables this cross talk.  The GBA connection links your central nervous system (CNS), including your brain, with the Enteric Nervous System (ENS) within your gut.  

The emerging field of Nutritional Psychiatry has shown that imbalances to emotional health are mostly associated with hormones, neurotransmitters, microbiota, and micronutrients, coupled with imbalanced blood glucose, resulting in the production of the stress hormone, cortisol. Fortunately, lots can be done to nourish our brilliant brains and tired adrenal glands with targeted nutrition interventions offering support to these factors.  

How do I improve gut health for mental health?

Although research continues, some evidence suggests that owing to the intimate link between the GBA, a first and fundamental step is to feed and fuel the gut microbiota.

🍌 Fibre

Prebiotics are specific types of fibre that aren’t digestible by your body. They can be found in leeks, garlic, onions, oats, asparagus, and bananas.  These specific fibres help feed the beneficial gut bacteria and produce anti-inflammatory substances called short chain fatty acids (SCFAs) of which the most common types are butyrate, acetate, and propionate. 

🍶 Fermented foods

Other ways that may improve gut health is by increasing fermented food such as miso, sauerkraut, kimchi, kefir, kombucha. Fermented food contains live beneficial bacteria, which support the diversity of bacteria within the gut. 

🍣 Essential Fatty Acids, (EFAs)

Particularly omega 3 polyunsaturated fatty acids (PUFAS) found in oily fish, walnut, hemp, and chia seeds are beneficial for brain health and function. 


The SMILES trial, conducted in 2017, was a poignant study which found that those following a Mediterranean based diet,  experienced significant improvement in their mental wellbeing,  and although future human trials are necessary, overall, one of the best ways to support mental health via the gut is by eating a wide variety of plant based whole foods, including a bounty of vegetables, wholegrains, nuts and seeds, herbs, and spices.



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