Does your gut affect your mental health?

How your gut affects your mental health:

There is growing evidence that the gut microbiota, our collection of bacteria that live in the gut, play an important role in depression and mood disorders as these microorganisms produce different neurochemicals which our brains utilise to remember, learn and even regulate our mood.

Read on for a deep dive into how looking after our gut health can have a positive knock-on effect on our mood and happiness too!

How gut health and our mood are related:

Ever heard of the gut-brain axis? You’re not alone if you haven’t. The gut-brain axis describes the relationship that occurs between the gut and the central nervous system, also known as the brain. The gut-brain axis encompasses the way in which your gut and brain communicate and work with each other, at both chemical and hormonal levels. There are 3 main neurotransmitters/compounds that play a role in this connection including serotonin, GABA and short-chain fatty acids. 

SEROTONIN- The gut is often referred to as our second brain – and for a good reason! Serotonin, our feel good happy hormone,  plays a vital role in the communication between the gut and the brain, in addition to the proper functioning of the gut. (1)

Serotonin is a neurotransmitter, also known as a chemical messenger, that has the ability to control and stabilise mood and brain functions, and over 95% of serotonin is created in the gut! What better excuse to look after your gut health! Fluctuations in serotonin levels can impact your gut health as well as brain health. Low levels of serotonin may impact mood, leave individuals feeling low, anxious and in the long-term even depressed. 

Serotonin is vital for gut function, controlling:

  • How fast food moves through your system
  • How much fluid is secreted into your intestines
  • How sensitive your intestines are to different sensations such as pain and fullness 

GABA – The brain contains many neurotransmitters that trigger or inhibit special reactions in the body. Gaba aminobutyric acid (GABA) is an amino acid that works as a neurotransmitter in the brain. GABA is an inhibitory neurotransmitter as it blocks certain brain signals and decreases activity in the nervous system, and can work to help calm the nervous system. This is why GABA is often referred to as the calming, anti-anxiety brain hormone. 

Low levels of GABA have been linked to mood disorders, chronic pain and anxiety. Common environmental factors such as stress and excessive alcohol use may also decrease GABA, which can result in symptoms of depression (2). If GABA is not released efficiently in the body, it can impact mental health and contribute to disorders of the brain and nervous system. (3) 

SHORT CHAIN FATTY ACIDS (SCFAs)- SCFAs are produced by the friendly bacteria in the gut, and are the main source of nutrition for the cells in our colon. Studies have shown the correlation between a higher intake of plant foods and increased levels of short-chain fatty acids in stool! (4)

In addition to SCFAs being crucial for gut health, they also play an important role in our mental wellbeing. They have the ability to influence emotional problems and cognitive disorders, in addition to stimulating the production of serotonin and other gut hormones. SCFAs can also directly affect the vagus nerve, which connects the brain and the gut. They do this by helping the body respond to inflammation and the production of neural growth and development.  

Overall, keeping our gut bacteria balanced and thriving is key for the production of these important neurotransmitters to further avoid alterations in mood, energy, sleep patterns, memory, concentration, managing stress levels and more. So now to the juicy bit – what can we do to support a healthy gut population? Read on.

Tips to support your mental health through your gut health

  • Meditation and gentle exercise are known to increase the production of neurotransmitters- try swapping your HIIT or spin class for some pilates or yoga to give your gut and stress levels some love. (6)
  • Get extra diversity in your diet- aim to include a range of colourful fruits and vegetables at every meal as a more diverse microbiome is usually a healthier one.
  • Include fermented foods that contain live strains of beneficial bacteria – try kimchi, kombucha, kefir and sauerkraut three times a week.
  • Include prebiotic foods as these insoluble fibres will help to feed the existing microorganisms in the gut. Consume raw garlic, onions, asparagus, leeks, flax seeds, Jerusalem artichokes and apples on the regular!
  • Up your protein- ensure you are consuming enough protein, especially highlighting tryptophan which is an essential amino acid that is a precursor to the production of serotonin. Think organic turkey, oats, nuts and seeds. 

References:

https://pubmed.ncbi.nlm.nih.gov/15790796/ (1)

https://pubmed.ncbi.nlm.nih.gov/8550953/ (2)

https://www.frontiersin.org/articles/10.3389/fncel.2014.00119/full (3) 

https://pubmed.ncbi.nlm.nih.gov/26416813/ (4)

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8428857/ (5)

https://commons.clarku.edu/cgi/viewcontent.cgi?article=1017&context=surj (6)