The mind-gut connection: Exploring the relationship between mental and digestive health
Ever had a ‘gut feeling’ about something? Or felt queasy before a big moment? Turns out, that’s not just a figure of speech, your gut and brain are in constant communication, influencing everything from your mood to how well you handle stress. Scientists call this the gut-brain axis, and it’s a two-way street impacting everything from our emotions and how well we handle stress to our physical wellbeing.
So, how does this connection work, and what can you do to support both your mind and your gut?
Understanding the gut-brain axis
The gut-brain axis is the name for the intricate communication pathway between our brain and our gut. This system includes the nervous system, immune system and hormones, which work together to send signals back and forth.
One of the key players in this axis is the vagus nerve, which acts like a communication superhighway connecting the brain to the gut. The brain can influence gut function through neural signals, and the gut can send signals to the brain that affect our mood, stress levels and cognitive function. But it's not just about the nerve pathways – hormones and immune responses also play major roles in this to-and-fro interaction.
When we're stressed, for example, our brain signals the gut to slow down or speed up, which can lead to symptoms like nausea, constipation or diarrhea. On the flip side, gut-related issues can also impact mental health, with imbalances in the gut microbiome triggering or worsening conditions like anxiety and depression.
The impact of mental health on gut health
When we're stressed our body releases cortisol, a hormone that can affect the way our digestive system functions. High levels of cortisol can increase gut permeability (also known as leaky gut), which can lead to inflammation and digestive issues.
How stress affects the gut
Stress and gut health are more connected than you might think. Research shows that stress can contribute to conditions like Irritable Bowel Syndrome (IBS), bringing on symptoms like stomach pain, bloating, and irregular digestion. Since IBS is a stress-sensitive disorder, feeling overwhelmed or anxious can not only trigger it but also make symptoms worse.
Anxiety and depression: The gut’s emotional triggers
The gut is often referred to as our "second brain" because of the vast number of neurons in the digestive system. When we’re feeling anxious or depressed, the gut's neurons are activated, leading to changes in digestion and gut motility (the movement of food, liquids and waste through the digestive tract). People with depression, for instance, often suffer from digestive issues such as constipation, bloating or stomach discomfort.
The role of the microbiome on mental health
The gut microbiome refers to the trillions of micro-organisms – bacteria, viruses, fungi and other microbes – that live in our intestines. These play a vital role in mental health. In fact, the gut microbiome has been linked to the production of serotonin, the "feel-good" hormone. About 95% of serotonin is produced in the gut, not the brain.
When the balance of gut bacteria is disrupted, it can affect the production of neurotransmitters (serotonin being one of them), which positively affect mood and cognition.
How to improve your gut health
Taking care of your microbiome, managing stress, and making healthy lifestyle choices can do wonders for both your body and mind. So, how can you support your gut health?
Eat well: A balanced diet packed with fibre, healthy fats, and plenty of fruits and veggies helps keep your gut microbiome thriving. Foods rich in polyphenols and antioxidants – like berries, dark chocolate, coffee, olives, and broccoli – are also great for gut health.
Related: how improving your gut health can support your immune system
Boost good bacteria: Probiotics are live, beneficial bacteria found in fermented foods like yoghurt, kefir, and sauerkraut. Prebiotics, on the other hand, feed those good bacteria, helping them grow. You’ll find prebiotics naturally in onions, beetroot, peas, asparagus, grains, legumes and some nuts and fruit.
Manage stress: Your gut and brain are closely linked, so keeping stress in check can help. Mindfulness meditation, yoga, and regular exercise are all great ways to support both your microbiome and your mental wellbeing. Discover more mental wellbeing techniques on The Check Up.
When should I speak with a GP?
If you’ve been dealing with ongoing digestive troubles – like bloating, constipation, diarrhoea or stomach cramps – and they get worse when you’re stressed, it might be time to talk to your GP. The same goes if you’re often feeling anxious, sad or irritable– especially if it’s starting to affect your everyday life. Changes in your appetite, weight loss or signs you’re not getting enough nutrients can also mean your gut and mind aren’t working well together.
Need to chat with a medical doctor? nib members can book a telehealth appointment with a medical doctor or nurse practitioner through our partner hub.health using the nib App.
If you or someone you know needs help, please call:
Lifeline 13 11 14
Beyond Blue 1300 22 4636
The information on this page is general information and should not be used to diagnose or treat a health problem or disease. Do not use the information found on this page as a substitute for professional health care advice. Any information you find on this page or on external sites which are linked to on this page should be verified with your professional healthcare provider.