April 19, 2023

Is it stress, or IBS?

April is IBS Awareness month, so KIC’s resident dietitian, Liv Morrison, answers all our burning questions about gut health and the link between stress & IBS.

1. Can stress or poor mental health cause IBS?


Although the research on irritable bowel syndrome (IBS) is constantly being updated, developing this digestive condition after a period of extreme stress, chronic stress, depression, anxiety or a traumatic event is a known cause and aggravator of symptoms.

Between 40%-60% of people with anxiety or depression develop IBS and up to 50% of individuals with IBS have experienced psychological trauma the year prior to diagnosis.

Traumatic events like; a death of a loved one, breakdown of a serious relationship, sexual or emotional abuse are linked to developing IBS.
This is why the most effective IBS treatments focus on stress reduction and management. 

When considering the 2022 Australian mental health statistics show that 1 in 2 Aussie women are currently experiencing psychological distress, it’s not surprising that majority of the 30% of Australians diagnosed with IBS are female. 

2. What is stress?

Before we jump into the relationship between stress & IBS, it’s important to understand what stress is & how it affects your body… 

Stress is a natural, protective response to situations that demand action, triggering the sympathetic nervous system (SNS) or the ‘fight, flight, freeze, faun’ reaction, to escape from a perceived threat. 

This happens by our brain recognising stress hormones (adrenaline, noradrenaline, cortisol) and an increase in heart rate, causing mobilisation of glucose into the blood stream to provide our muscles with energy to run away. At the same time, our body reduces blood flow to other organs and slows digestive processes to allow our us to focus on survival.

Although it sounds worst-case scenario, our body also does this even with positive forms of stress, called ‘Eustress’, which occurs we feel positive emotions like excitement or when we’re simply going to a run. 

Once the ‘threat’ is gone, our body returns to normal and relaxes. The issue arises with chronic stress as our body can’t return to baseline, forced to constantly react and adapt to stressors, to the point where your body can no longer effectively deal with the stressor.

As a result, this long-term stress can cause numerous, scary health conditions including; poor immunity, inflammatory conditions, heart disease, stroke, various cancers, weight gain, infertility and psychological conditions.

You may not be aware of the added stress you are under but learning to recognize the symptoms of stress is the first step in effectively managing it.

Some signs of excessive stress include:

  • Difficulty sleeping or insomnia. 
  • Irritability or moodiness.
  • Decreased satisfaction with tasks.
  • A persistent feeling of urgency.
  • Clammy and sweaty hands.
  • Cold hands and feet.
  • Tension headaches, backaches, stomach-aches or other physical discomforts.

3. Why does stress cause digestive symptoms?

As your body activates the SNS ‘flight, fright, freeze, faun’ nervous system in response to stress, it reduces blood flow and energy to the gastrointestinal tract (GIT). When we’re in this stressed state, our stomach and intestines aren’t able to digest, squeeze and move food through the bowel properly which can cause a lot of digestive discomfort. 

This stress-response also acts on the gut-brain axis and microbiota-gut-brain axis, which affects gut function and composition of good vs bad gut bacteria. Our gut bugs and brain are in constant communication so when we don’t have enough positive bacteria interacting with our brain, our physical and mental health are negatively affected. 

Stress causes other physical changes that lead to IBS. It increases pain perception, which can cause us to be highly sensitive and conscious of bodily sensations leading to abdominal pain. When we’re stressed, we’re also more likely to crave and consume unhealthy foods that can trigger GI discomfort e.g., foods high in sugar and fat, alcohol, caffeine and tobacco. 

It’s a vicious cycle… high stress can trigger IBS symptoms (stress-induced IBS) and then those digestive symptoms often increase stress!

Without this response to stress, we wouldn’t have made it far when we were living in a cave. However unfortunately for us, in today’s society we are still wired the same. We’ve swapped running from animals for deadlines, unescapable online bullying & never-ending emails. 

4. How can I tell if my stomach issues are caused by stress or from something more serious?

As IBS is a stress sensitive disorder, it can be hard to tell if what you’re experiencing is a just bodily response to heightened stress or a food intolerance, allergy or more serious health condition.

Symptoms to look out for are:

  • Diarrhoea.
  • Constipation.
  • Nausea.
  • Vomiting.
  • Gas and flatulence.
  • Bloating. 
  • Abdominal pain and cramps.
  • Headaches and migraines. 
  • Reflux or heartburn.
  • Changes in the colour of your poo e.g., pale, green, very dark. 
  • Rashes, hives or itching. 
  • Mood change. 
  • Changes to your menstrual cycle.  

I highly recommend tracking your symptoms either in your phone, on paper or a food-symptom-diary app over a few weeks-months and taking note of changes in your diet, stress, sleep quality, menstrual cycle and exercise. 

The more detailed you are in your note taking, the easier it is for a professional to help you if need be. Rating your symptoms severity out of 5 or 10 and tracking bowel movements on the Bristol Stool Chart are great ways to do this. If your IBS symptoms are mild, very infrequent and align more with your mood, it’s likely stress-induced IBS.

If you are concerned, regardless of how mild or few symptoms you may have, there is no harm in seeing a health professional!

5. How do I know when to seek professional help? Who should I go to?

Ideally, we should all be checking in with our GP at least once a year. It’s a great opportunity to tell them about your digestive issues so they can support you, pick up on any warning signs early and refer you to a Gastroenterologist or dietitian.

A Gastroenterologist can determine whether your symptoms are due to stress or due to another condition. 

If you are experiencing any of the below symptoms, it’s best to book in with your GP… 

  • Unintentional weight loss
  • Increased bruising
  • Shortness of breath or difficulty breathing.
  • Chest pain.
  • Noticing blood, pus, black or very dark stools.
  • Bruising easily.
  • Excessive hair loss.
  • Wounds or cuts not healing quickly. 

If you have a family history of Crohns Disease, Ulcerative Colitis, Coeliac Disease, bowel, stomach or pancreatic cancer, let your GP know as sometimes these genetic conditions are best prevented by regular screening.

Liv Morrison