Gut, brain and sleep
IBS and anxiety: how they are linked, and what helps both
IBS and anxiety often occur together. In pooled studies, about four in ten people with IBS have symptoms of anxiety and about three in ten have symptoms of depression. Neither is simply the cause of the other. They share nerve pathways and stress chemistry, and each makes the other worse. Several treatments help both at once, including cognitive behavioural therapy, regular exercise and, where needed, medicines that act on the nerves of the gut.
In short
- IBS is a disorder of gut-brain signalling. It is not a mental illness, and anxiety is not a weakness.
- In a 12-year study, anxiety predicted later gut disorders, and gut disorders predicted later anxiety.
- Psychological therapies designed for IBS reduce gut symptoms in trials.
- Treating one condition usually eases the other.
Why do IBS and anxiety occur together?
Shared wiring
The gut and the brain are linked by the vagus nerve and by stress hormones. An alert nervous system speeds up the colon and makes the gut more sensitive.
A circle that feeds itself
Symptoms cause worry about the next episode: where the toilet is, what to eat, whether to travel. That worry keeps the nervous system alert, which brings on more symptoms.
A common starting point
IBS often begins after a gut infection. Psychological distress around the time of the infection raises the chance that IBS will follow.
Sleep
Both conditions disturb sleep, and poor sleep worsens both.
A circle that feeds itself. Symptoms cause worry about the next episode. That worry keeps the nervous system alert, which brings on more symptoms.
Which comes first?
Either. In a study that followed about 1,000 adults for 12 years, people who had anxiety but no gut disorder at the start were more likely to develop one. People who had a gut disorder but no anxiety at the start were more likely to develop anxiety or low mood.
About 1,000 adults, followed for 12 years
- Anxiety, but no gut disorder, at the start more likely to develop a gut disorder
- A gut disorder, but no anxiety, at the start more likely to develop anxiety or low mood
How do I know if anxiety is part of my IBS?
- Symptoms flare before meetings, travel or social events
- You plan your day around toilets
- You avoid eating out, long journeys or certain foods out of fear, not because of a clear reaction
- You check your body for symptoms through the day
- Sleep is poor, and worries are hard to switch off
- You have a racing heart, sweating or restlessness
Which treatments help both?
| Treatment | Effect on IBS | Effect on anxiety |
|---|---|---|
| Cognitive behavioural therapy for IBS | Among the psychological therapies with the most evidence | Treats anxiety directly |
| Gut-directed hypnotherapy | In one trial, 41% of patients had adequate relief with individual sessions, compared with 17% with education alone | Eases gut-focused worry. It is not a treatment for an anxiety disorder. |
| Regular exercise | Improved IBS severity in a randomised trial | Benefits mood and anxiety as well |
| Yoga | Six small trials suggest fewer bowel symptoms. Their quality was limited. | The same trials reported less anxiety |
| Low-dose medicines that calm gut nerves | Reduce pain and urgency | Little effect at these doses. A different medicine or dose is chosen when anxiety is prominent. |
| Sleep correction | Lowers gut sensitivity | Lowers anxiety |
Both therapies are available through my centre. See gut-directed hypnotherapy and CBT and low-dose antidepressants for gut pain.
What can I do myself?
Keep a two-week diary
Note symptoms, meals, sleep and stressful events. Patterns become visible, and many feared foods turn out to be innocent.
Practise slow breathing daily
Five to ten minutes, twice a day. See ways to stimulate the vagus nerve.
Move on most days
A brisk walk of 20 to 30 minutes is a good start.
Return to what you have been avoiding, in steps
A short outing first, then a longer one. Each one that goes well lowers the alarm for the next.
Do not over-restrict food
Long lists of banned foods add worry and can worsen symptoms. Use a low FODMAP diet only for a limited period, with guidance.
Cut down caffeine
It stimulates both the bowel and the nervous system.
A short guided breathing practice to follow along with.
When should I see a doctor?
See a doctor promptly for blood in the stool, weight loss, fever, anaemia or symptoms that wake you from sleep. These are not features of IBS or of anxiety.
See a doctor, a psychiatrist or a psychologist if anxiety or low mood has lasted more than two weeks, if you have panic attacks, or if you are avoiding work or travel. Tele-MANAS, the Government of India’s free mental health helpline, is available on 14416.
Questions patients ask me
Can anxiety cause IBS?
Anxiety raises the risk of IBS and worsens its symptoms, but it is not the only cause. Gut infections, gut bacteria, food and the sensitivity of gut nerves all play a part.
Can IBS cause anxiety or panic attacks?
It can contribute. Unpredictable symptoms create worry, and in long-term studies people with a gut disorder were more likely to develop anxiety later.
Does yoga help IBS and anxiety?
Small trials suggest that it reduces both bowel symptoms and anxiety, though the studies had weaknesses. It is a reasonable addition to treatment, and it is taught in my integrative medicine centre.
Will a medicine for anxiety help my IBS?
It depends on the medicine. Some act mainly on mood and some mainly on gut pain. The choice is made after an assessment of which symptoms trouble you most.
Is IBS a mental illness?
No. It is a disorder of how the gut and the brain signal to each other, with measurable changes in gut sensitivity and movement.
Sources
This page is written for patients and is based on the guidelines and studies below. It is for education and does not replace a consultation.
- Meta-analysis of anxiety and depression in irritable bowel syndrome. Zamani M et al. Aliment Pharmacol Ther. 2019. PubMed 31157418
- Twelve-year study showing the brain-gut pathway runs in both directions. Koloski NA et al. Gut. 2012. PubMed 22234979
- Rome Foundation report on irritable bowel syndrome that follows a gut infection. Barbara G et al. Gastroenterology. 2019. PubMed 30009817
- Network meta-analysis of psychological therapies for irritable bowel syndrome. Black CJ et al. Gut. 2020. PubMed 32276950
- Trial of individual and group hypnotherapy for irritable bowel syndrome. Flik CE et al. Lancet Gastroenterol Hepatol. 2019. PubMed 30473202
- Trial of physical activity for irritable bowel syndrome. Johannesson E et al. Am J Gastroenterol. 2011. PubMed 21206488
- Systematic review of yoga for irritable bowel syndrome. Schumann D et al. Clin Gastroenterol Hepatol. 2016. PubMed 27112106
- Rome Foundation report on neuromodulators for gut-brain interaction disorders. Drossman DA et al. Gastroenterology. 2018. PubMed 29274869
- American College of Gastroenterology guideline on irritable bowel syndrome. Lacy BE et al. Am J Gastroenterol. 2021. doi:10.14309/ajg.0000000000001036