Our ‘second’ brain: an investigation into the gut-brain axis

The Vitl Nutrition Team / 7 Sept 2021

Our in-house nutritionist takes a deep dive into the gut-brain axis.


You may have heard it before, but recent research suggests that our gut is our ‘second’ brain. What does that mean? Our nutritionists delve into the details…

Did you know that your gut microbiome weighs about 1-2kg, which is about the same as your brain? In fact, the microbiome is made up of trillions of microbes in the gut and plays a crucial role in our health. There is a growing body of research to suggest that the gut also regulates our mood, which might make sense considering that only 10% of the nerves that connect the brain with the gut (through the vagus nerve), deliver information from the brain to the gut. 

The other 90% of the nerves are actually sending information from the gut to the brain. Quite interesting right? 1 The gut and brain are so interconnected that in stressful situations, your gut will stop working (ie. digesting) to save energy for the brain to use to deal with the stressor.

So other than digesting our food what does our microbiome do? Our intestinal tract is about 40 times the surface area of our skin, it is the largest sensory organ in the body. It houses 100 trillion microorganisms that are doing all sorts of things; from training immune cells to synthesising certain vitamins from the food we eat (mostly the high fibre, indigestible foods) 2.

The nervous system is so complex in our gut that it is very sensitive to emotion. Do you know the feeling that you get before an interview or a big speech? Well, that feeling in your stomach is your gut responding to your environment. 

‌The gut-brain link is bidirectional and a dysbiosis* in the gut can cause inflammation, which may be the cause of certain mental health disorders 3. A disturbance in the gut results in disturbances in the hormone, neurotransmitter and immunological functions. This is the main reason that gut health is being warranted as an important player in achieving overall health 4

Certain interventions such as the consumption of probiotics have been looked at for the mitigation of anxiety or depression symptoms with some positive outcomes. More research is still needed, but so far evidence has shown a link between supplementing probiotics to improve the gut microflora 5.

Research suggests that IBS and IBD sufferers have a higher risk of developing anxiety and depression. This may be attributed to the concept that the gut is closely connected with the brain, however, the consensus is not completely clear yet from the research. 

A 2020 survey showed that 90% of the global population considers itself as ‘stressed’, with 95% stating that their stress and anxiety levels have an impact on their health. Feelings of stress can cause an imbalance in our microbiome, which may lead to inflammation and dysbiosis. 

At Vitl, we have developed a Tranquility blend to target stress and help improve sleep. Stress has been identified as one of our top goals by customers. The blend is formulated with calming plant extracts like ashwagandha and lemon balm to help you keep calm and prepare for a restful night's sleep. 

In a nutshell, a happy gut = a happy you.

We’ve also developed a Limited Edition Mind & Body to help support you to feel better, look better, sleep better and focus better. 

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