Is the gut-brain axis the key to better health?

Happy young woman with long brunette hair laughing and enjoy the outdoors
3 November 2021|5 min read

Key points about the gut-brain axis

  • Science is starting to understand that a major part of the gut’s job description is related to the gut-brain connection, known as the gut-brain axis.
  • Supporting a healthy gut is important for a well functioning gut-brain axis to send positive healthy messages to your brain.
  • It's a good idea to seek help from a health professional to understand your gut health.

Ever had a ‘gut feeling’ that something isn’t right? Had butterflies in your stomach when you were nervous about an event? There might be more to that connection than many of us realise.

Ongoing research into gut health and its connection to the rest of the body’s overall health is allowing us to explore the relationship between the gut and the brain. This connection has been coined the ‘gut-brain axis’, and it could potentially affect other parts of our lives.

Let’s start with the science

While the gut technically starts at your mouth, the majority of the gut is housed inside your abdomen. The gut’s main job is digesting food, releasing the nutrients into the bloodstream and escorting the waste out the back door.

The body is great at letting us know when something is not quite right.

Sarah Gray - Pharmacist & Nutritionist

Science is starting to understand that another major part of the gut’s job description is related to the gut-brain connection. 

The gut-brain axis is the communication link between the central nervous system, which consists of the brain and the spinal cord, and the enteric nervous system which controls the digestive system. It links the interaction of the emotional and thought processing parts of the brain with intestinal functions. The enteric nervous system is affectionately known in scientific circles as the ‘second brain’. 

Registered Pharmacist and Registered Nutritionist Sarah Gray explains that the research being released shows “how important gut health is to not only digestive health, but other areas such as the immune system and mental wellbeing, to name a few.”

Communication is a two-way street

The research into the gut-brain axis is starting to show how crucial this link is. But it’s important to understand how the communication link works so it may be maintained at that optimum level. And that it's a two-way link – not just top-down. 

low FODMAP diet
The link between IBS and stress

The link between IBS and stress

There's more than one thing that can trigger IBS symptoms, including stress. Find out how your mood and stress can affect IBS and why it's not a one way street.

read more

So, it’s not just about the brain feeding information down to your gut and telling it how to respond. The gut has its own response and sends those messages to the brain, potentially changing the brain’s activity. 

For example, research is starting to uncover how changes in the gut, such as inflammation, may potentially change the messages being sent to the brain via the gut-brain axis. 

Factors such as stress have been considered a possible cause of certain issues in the gut. But with the increased understanding around the two-way link, recent research is now suggesting it could be the other way around. 

Basically, you might have thought it was being stressed which caused something like diarrhoea. But it could possibly be the changes in your gut causing the diarrhoea that are sending stress messages to your brain. 

A man stares into the camera, he looks serious and a little concerned. Perhaps about his gut bacteria and brain health?

The gut-brain axis could potentially affect other parts of our lives.

What could affect the gut-brain axis?

If your intestines are affected by the health of your gut microbiome, this may potentially link the health of your gut with things like your mental wellbeing. So, if you’re worried about something, you may possibly feel queasy in your stomach due to the gut-brain axis.

Poor gut health may have effects such as:

  • Low production levels of serotonin, which plays a role in many functions, including controlling wellbeing and happiness. Your gut creates 95% of the body’s supply of serotonin, and 90% of serotonin receptors are located in the gut. And, as we know, serotonin influences mood. 
  • Too much histamine in the gut, which could have an impact on the brain and cause what’s known as ‘brain fog
On a table, two glasses of yogurt stand on a wooden chopping board. One is still being poured.

The benefits of fermented foods, which include creating probiotics, have been shown to help support a healthy gut.

Ways to support a healthy gut-brain axis

Understanding all those intricate connections is complicated and studies are still in their early stages. But one thing is clear: supporting a healthy gut is important for a well functioning gut-brain axis to send positive healthy messages to your brain.

Sarah says there isn’t a blanket list of ‘bad’ foods for gut health. But it's a good idea to seek help from a health professional to understand any food triggers you may have. 

gut health
What you need to know about how probiotics work

What you need to know about how probiotics work

Did you know that not all fermented foods contain live cultures? And that different strains of probiotics do different things?

read more

“Some people can be sensitive to certain foods, and a dietitian can assist with a special plan to remove and re-introduce these over time,” she says.

Learning how to improve gut health and what foods could improve your gut health is a good way to start. As your gut microbiome is as unique as your own fingerprint, it's important to learn what works for your body.

The benefits of fermented foods, which include probiotics, have been shown to help support a healthy gut. And the use of probiotics has shown connections between gut bacteria and brain health.

A 2018 study looked at a range of foods to determine which were the most effective at increasing mental wellness. It found that “the highest-scoring foods were bivalves, such as oysters and mussels, various seafood and organ meats for animal foods. The highest scoring plant foods were leafy greens, lettuces, peppers and cruciferous vegetables.”

A man stares into the camera - he looks satisfied and content.

A healthy gut is important for a well functioning gut-brain axis to send positive healthy messages to your brain.

Healthy gut + healthy brain = healthy gut-brain axis

“The body is great at letting us know when something is not quite right,” concludes Sarah. 

When you recognise these signs and what they could possibly mean for your body, you could take a step towards knowing what to do to improve your overall health. 

If you have any concerns with your health, your first stop needs to be a health professional such as your GP. Having healthy connections with your GP could lead to healthy connections with your body and your gut-brain axis.

Related:

Sarah Gray is both a Registered Pharmacist and Registered Nutritionist with a particular interest in health education and helping people to take small steps to big change in their health journey. Sarah is the Head of Health and Nutrition on the healthylife Advisory Panel.

Reviewed by the healthylife Advisory Board October 2021.

Spread the word

This article is for informational purposes only and does not provide medical advice, diagnosis, or treatment. Any information published on this website or by this brand is not intended as a substitute for medical advice. If you have any concerns or questions about your health you should consult with a health professional.