Are your stomach problems caused by stress? What is ‘leaky gut’, and expert tips to avoid it

How does stress affect gut health?

To understand the impact stress has on your digestion and gut health, it's firstly important to understand exactly how the brain and the gut is connected – through something called the gut-brain axis.

“It’s essentially a communication network involving the brain, spinal cord, the enteric nervous system (our gut's own nervous system) and our gut microbiome,” explains Dr Sarah Bonza. “This connection allows exchanges of messages via nerve pathways like the vagus nerve and other biochemical signals like hormones.”

This means when you’re exposed to something like stress, it can disrupt this complex connection. For example, a spike of cortisol (the body’s primary stress hormone) during a stressful event can affect how our intestines move and contract.

“Something like a cortisol spike can also increase gut permeability, which we call ‘leaky gut’. This can disturb the good microbiome in our gut and lead to symptoms like bloating, pain and bowel movement changes,” adds Dr Bonza.

What is ‘leaky gut’?

Leaky gut, also known as increased intestinal permeability, is a condition where the lining of the small intestine becomes damaged, causing undigested food particles, toxins, and bacteria to ‘leak’ through the intestinal wall and into the bloodstream. This can trigger inflammation and immune responses in the body, leading to a variety of potential health issues, one of them being poor digestion.

Persistent stress can weaken the immune system and increase gut permeability, as can other factors including a poor diet, an imbalance in gut bacteria, certain medications and conditions like Crohn’s disease, coeliac disease, and irritable bowel syndrome (IBS).

If you’re suffering with leaky gut, or to tell if stress is affecting your gut, you should look out for indications like digestive problems, food sensitivities and even persistent tiredness.

“You might have symptoms like bloating, feeling gassy, cramping, diarrhoea, constipation, acid reflux, appetite changes, nausea, and possibly vomiting,” notes Dr Bonza.

Gut health connection is way more important than you think, and the long-term effects of chronic stress on your gut is profound – and can even go as far as causing the development of conditions like IBS, gastroesophageal reflux disease (GERD), and ulcers.

“Stress can also exacerbate existing digestive disorders if you have them,” warns Dr Bonza. “Furthermore, constant stress can affect your digestion and ability to absorb nutrients, so you can develop nutrient deficiencies, changes in weight, and as expected, since your body isn't nourished, your immune system weakens, making you’re prone to inflammation and more diseases. It's really a huge chain reaction.”

6 ways to de-stress your gut:

Introduce strength training to your exercise routine

Exercise is an amazing way to de-stress, and therefore one of the best (and free!) tools we have to boost our gut health. And while exercise in general is an excellent way to de-stress your brain and your gut, strength training is particularly beneficial.

“Strength training is a great way to boost the gut, not only from, a de-stress perspective,” explains personal trainer and women’s health coach Emma Simarro. “It has been proven to help reduce inflammation in the gut by boosting certain anti-inflammatory proteins.”

Meditative forms of exercise, including yoga and pilates, are also fantastic, but if you’re someone who likes to get sweaty through HIIT sessions or running, Simarro has a word of warning. “If that is what you like to do to de-stress, that’s fine, however, I would specify that doing too much of very intense forms of exercise could work against you,” she says.

“Try and really balance it out. That may be two intense HIIT sessions a week, mixed with some yoga and strength training, so you've got a good balance across the board.”

Support your gut bacteria

Probiotics and prebiotics can easily be mistaken as a gimmick, but they can in fact help restore a health balance of gut microbiota in your system.

“Probiotics are foods that have beneficial bacteria in them, while prebiotics are foods that ‘feed’ the bacteria,” explains registered nutritionist Michaella Mazzoni. “Fermented foods like yogurt, kefir, sauerkraut and kimchi are all great sources of probiotics, while prebiotics include things like garlic, onions, oats and stewed apples.”

A healthy gut breakfast could look something like a bowl of porridge, topped with nuts, seeds and cooked apples, for example. Chickpeas, lentils and foods that contain resveratrol (red grapes and red onions), are also great for feeding the gut too, adds Mazzoni.

Introduce breathing exercises

The right breathing techniques can positively impact our gut health, especially when we focus on ‘upregulating’ – increasing the activity of the parasympathetic nervous system (PNS) which promotes relaxation, digestion and recovery.

“The sympathetic nervous part of our nervous system, which most of us spend a lot of time in, is that ‘fight or flight’, high-stress part,” explains Simarro.

“Then we have the PNS, which we call the 'rest and digest' part of our nervous system, and this is where the breathing techniques really come into play. We want to upregulate that PNS, as it’ll help our whole body to calm down and relax. Breathing techniques can especially help with this.”

Two breathing techniques to try:

Nostril breathing

Take a deep breath out to get rid of all the air; then use your right thumb to close your right nostril, and take a big, deep breath in through your left nostril, and then close your left nostril and take a deep breath out through the right, and vice versa.

Belly breaths

If you watch a baby sleep, they breathe right into their bellies; they’re nice and relaxed. Sit, relax and take nice, big, deep belly breaths, breathing right into the ribcage.

Sleep better

Studies show that there’s a direct link between insomnia and lack of sleep and poor digestion, so improving your sleep hygiene can really help in getting your gut health on track.

“When you don’t sleep, you have a harder time managing your blood sugar and your cortisol the next day, which increases stress, which then impacts your gut,” warns Mazzoni.

Try to establish a good sleeping routine and avoid irritants and disruptions in the evening such as caffeine, alcohol and sugar. Instead, Mazzoni recommends factoring in better nutrients such as magnesium, zinc and omega 3.

Practice mindfulness

Like the breathing techniques, meditation and mindfulness is a great way to clear the mind, de-stress and upregulate the PNS mentioned earlier. In fact, it has been shown that meditation lowers oxygen levels, which in turn helps with greater blood flow and circulation. Proper circulation ensures that the gut receives the oxygen, nutrients, and immune support it needs to function properly, while also helping to remove waste products and toxins.

It's important to practice mindful eating too, according to Simarro. “Take your time when eating meals, chewing properly and sitting at the dinner table if you can,” she recommends. “Ways in which we can really calm the body down and increase relaxation, boost sleep and increase movement and mobility is really important.”

Improve your diet

It goes without saying, but bettering your diet by increasing your fibre intake, adding in those pre and probiotics that help support gut bacteria, and limiting processed foods can all help with better gut health.

It’s important to look at your caffeine intake, too. Caffeine, particularly in large amounts, can irritate the gut lining, increase cortisol, and stimulate the production of stomach acid.

“I often see people in my clinic that have switched to decaf to help with sleep, but decaf still affects the gut because it’s quite acidic,” warns Mazzoni. “So, if you do have issues around loose bowel movements and quick gut transit time – avoiding coffee completely, even decaf, is the best option. However, if you do want caffeine, try matcha – it has more caffeine in it than tea, and doesn’t damage the gut in the same way coffee does.”

It's important to note that if there are any changes in your bowel habits, and gut, or you have persistent symptoms, or symptoms that you’re concerned about, you should check in with your GP who can help investigate whether other factors can be involved aside from stress.

Read more about stress:

• What are the symptoms of stress?
• 10 tips to manage stress eating
• Why stress makes you hungry