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Your second brain: the gut-brain axis

1st May, 2023

Go with your gut!

‘Go with your gut’, ‘I’ve got a gut feeling’, ‘Butterflies in my tummy’. We’ve been using these tummy terms to talk about our feelings for decades, and now there’s science behind them too!

You see, our tummies and brains are closely connected, constantly chatting to each other with two-way communication. So much so, that our tummies almost act as a second brain, with the power to influence our emotions and mental wellbeing, as well as our physical health. Pretty amazing, right?

We call this special link the ‘gut-brain axis’. And the latest science suggests its power and potential for supporting our health and happiness could be huge.

So how does it work?

Just like you and your BFF, the brain and the tummy are there for each other for the good times and the bad. They can feel each other’s emotions, from happiness and excitement, to anxiety, nervousness, sadness and anger.

That means when things are smooth sailing, and you’re happy, calm and stress-free, a happy brain helps keep a happy tummy. Likewise, when your tummy is in tip-top condition, your brain can feel that boost too.

But what happens when this gut-brain communication goes out of order?

When one is troubled, they empathise with the other. And just like a burned-out brain sends messages to the tummy, a troubled tummy can send stress signals back up to the brain too.

Ever heard of the “fight or flight” response?

When you’re faced with a stressful event. The brain’s warning messages can shut down your digestion, so you have more energy directed to running away or fighting back.

This was useful in cavemen times when dealing with real threats, but not so much nowadays…

The thing is, our bodies still have a similar stress response today, ditching digestion and triggering tummy troubles like bloating, tummy pain and pooping problems.

BRAIN
You’re feeling stressed, so your brain releases chemicals like cortisol and adrenaline. These chemicals tell your tummy something is wrong.		Your brain receives stress signals from your tummy and it’s microbes. In response, your brain activates “fight or flight” mode.

TUMMMY
In true “fight or flight” response, your tummy – stops digesting food properly leading to an increase in tummy troubles like bloating, pain and problems pooping.		When your tummy is troubled your microbes also becomes distressed too. Together, your tummy and it’s microbes pump out chemicals that travel up through the vagus nerve to your brain.

Mighty microbes and your mind

One of the main things holding this relationship together is the community of trillions of tiny microbes in our tummies, the microbiome. This has lead scientists to rename it the gut-microbiome-brain axis.

Your gut microbiome refers to this mix of over 1,000 different types of microorganisms (mostly bacteria, as well as fungi and even viruses) in your gut. All together, they work hard in your tummy to keep you healthy, from helping your digestion, supporting your immune system and so many other parts of your overall health. You can read more about the gut microbiome here.

Your mighty microbes like to be balanced but this balance can be disturbed by a few different factors. As well as stress, things like what you eat (not getting a varied diet), as well as illnesses, antibiotics and other toxins in the environment can trigger your tummy and disrupt the balance of bacteria

When upset, your gut microbes start to send signals to your brain via the vagus nerve. The vagus nerve is basically a highway of nerves which connects the brain and gut.

For this gut-microbiome-brain communication to be working well, it’s always a good idea to give your tummy and it’s microbes a little extra TLC.

It’s our tummy, not our brain, that makes 90-95% of our serotonin!

So what can you do to look after your tummy and in turn help look after your mind?

The good news is there are simple steps you can take for a tip-top tummy, which could give your mental health a boost too.

Here are 4 ways to get your gut-brain axis back on track:

1.Mix up your meals.

Variety is the aim of the game, so try to pile up your plate with plenty of diverse, colourful plant-based foods – including fruit and veggies, wholegrains, beans and pulses, as well as nuts and seeds. They’re filled with fibre and packed with tummy-loving plant chemicals (called polyphenols) that nourish your friendly gut bugs.

Find out more about foods for your mood here

2. Move your muscles.

Exercise can be a great stress-reliever – and science shows moving your body could be linked with having more diverse microbes in your tummy (remember, we want a varied mix of microbes for the win!)

So whether it’s a yoga flow, a power walk or a sweaty sports session – aim to get your heart racing for 30 minutes regularly for your microbes (and your muscles).

3. Get some more shut-eye.

Sleep is super important for a healthy brain and a healthy tum. You might have felt the effects of poor sleep on your mood, and on your tummy. This goes both ways too, as having tummy troubles can also lead to sleep struggles.

We know it might be easier said than done, but clocking 7-8 hours of sleep every night could boost beneficial bacteria and help take care of your tummy health.

4. Mindfulness meditation

A bunch of scientific studies show practising mindfulness and breathing techniques could be just as effective for your tummy troubles as changing up your diet.

We know what you might be thinking – who has time for that in our busy lives? But hear us out. Even just 10 minutes of daily deep belly breathing or mindful meditations can help to relax and rewire the gut-brain axis. How? When we take the time for mindfulness and breathing, it helps to reset our body’s stress response – moving us from that “fight or flight” mode to “rest and digest”.

It could be just the thing that works wonders for the wellbeing of your tummy and your brain.

That’s the gut-brain basics covered – read on to dig deeper…

The role of your microbiome

We mentioned your microbiome as a key player when it comes to the gut-brain axis. So let’s dive a little deeper…

Those microbes influence a lot of the messages sent to the brain by:

Producing vitamins (including K and B vitamins) that are essential to lots of body processes.
Producing hormones like serotonin (aka ‘the happy hormone’) and dopamine (aka ‘the pleasure hormone’) that help to regulate digestion as well as brain functions.

But if your microbiome is messed with (such as by poor diet, infections, medications, as well as stress), this can disrupt the bacteria balance.

The result?

The diversity of microbes in your gut can be reduced and it’s this diversity that’s linked to better tummy and overall health. In turn, this can mean fewer important vitamins and hormones are produced in the gut, including serotonin and your mood can drop.

How exactly do they communicate?

The gut-brain axis links the brain’s central nervous system (CNS ) with the gut’s enteric nervous system (ENS). Our tummies and brains communicate with each other bidirectionally (aka both ways), sending messages to each other in two main ways:

Physical messages (via the Vagus nerve): Messages between your brain and your tummy can be physical, like two friends chatting face-to-face. These physical messages are sent by the vagus nerve. The vagus nerve is the main nerve of your parasympathetic nervous system, acting like a long highway carrying information between the two.

Chemical messages (via hormones): Messages can also be chemical, sent by hormones called neurotransmitters – just like two friends texting.

The brain and your bowels

This close friendship may also explain some longer lasting tummy troubles. In fact, irritable bowel syndrome (IBS) is considered to be a disorder of the gut-brain axis, where stress, alongside other factors, is thought to play a central role.

That’s why lifestyle changes targeted at reducing stress, like mindfulness, meditation and breathing exercises can be game-changing. They’re now even being prescribed for managing IBS symptoms – the link really is powerful!

More and more research is being done on this gut-brain connection every day and it’s becoming even more clear how strong this communication really is. We’re here to help you get on top of your tummy for the brain benefits and more.

Interested in the nitty gritty? Read the research

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Your second brain: the gut-brain axis

Go with your gut!

So how does it work?

Ever heard of the “fight or flight” response?

Mighty microbes and your mind

Here are 4 ways to get your gut-brain axis back on track:

1.Mix up your meals.

2. Move your muscles.

3. Get some more shut-eye.

4. Mindfulness meditation

The role of your microbiome

The result?

How exactly do they communicate?

The brain and your bowels

Interested in the nitty gritty? Read the research

Related articles

Want to be a part of the movement?

Let’s stay connected

Go with your gut!

So how does it work?

Ever heard of the “fight or flight” response?

Mighty microbes and your mind

Here are 4 ways to get your gut-brain axis back on track:

1.Mix up your meals.

2. Move your muscles.

3. Get some more shut-eye.

4. Mindfulness meditation

The role of your microbiome

The result?

How exactly do they communicate?

The brain and your bowels

Got tummy pains and diarrhoea?

Let’s stay connected