What is Irritable Bowel Syndrome?
Symptoms of Irritable Bowel Syndrome (IBS) include pain or discomfort in the lower abdomen (below the belly button area) and changes in bowel habit that involve frequent, urgent diarrhea or constipation. Bloating is another common symptom. IBS is a medical disorder primarily affecting the lower ‘gut’ (the small and large intestine) which is one part of the gastrointestinal (GI) tract.
IBS is a disorder of gut-brain interaction, meaning there are communication disruptions between the brain and the gut. IBS is understood to be a problem of the functioning of the gut. Research suggests that people with IBS experience abnormal gut motility (changes in the rate of contractions of the gut muscles), enhanced visceral sensitivity (an increased sensitivity to gas or sensations from routine activities that occur in the bowel), and changes in the gut microbiome (communities of microbes in the digestive tract, made up of bacteria, fungi, and viruses that, when balanced, help with digestion, nutrient absorption, and immune function).
It is not clearly understood what causes IBS. For some people it begins in childhood with a ‘sensitive stomach’ that develops into more intense symptoms as an adult; for others, the GI problems start suddenly during a period of stress or persist after an infection in the bowel. IBS is diagnosed based on the presence of the symptoms described above in combination with the absence of other ‘red flag’ symptoms (such as weight loss or bleeding).
IBS is very common. It is estimated to affect up to one in five Canadians. It often starts in young adulthood and occurs much more frequently in women than men. It is the second most common reason for missing work and is one of the most common reasons that people visit their doctor. In Canada, IBS has been estimated to cost over $350 million in direct and over $1 billion in indirect health care and productivity costs each year.
While the impact on society is quite significant, IBS can be very challenging for the individual. Pain, cramping, or urgent trips to the washroom may interfere with work and home activities. The bloating, gas, and urgency can be embarrassing, so people often suffer in silence.
Many people think certain foods must be the culprit but there is no evidence to support the idea that IBS is directly related to food allergies or food sensitivity. Once IBS develops, however, the bowel is over-reactive to or easily disrupted by a variety of potential triggers including diet, stress, emotional state, and even hormone fluctuations.
Stress does not cause IBS, but it does appear to play a particularly important role in triggering IBS symptoms, likely because of the close communication via nerves and chemical pathways between the brain and the gut. In fact, two-thirds of healthy individuals without IBS report GI symptoms of pain or bowel upset in response to stress and the numbers are even higher for people with IBS.
Research suggests that both ‘acute stressors’ such as deadlines, exams, job interviews, or conflict with others as well as ‘chronic stressors’ such as financial concerns, time pressures, or family issues can aggravate the gut.
How Can Psychology Help?
For those with milder IBS symptoms, use of over-the-counter medications and changes in lifestyle that ensure more regular eating and sleep routines, a healthier diet with increased fibre and water intake, as well as more regular moderate intensity exercise such as walking, swimming, or cycling, are usually sufficient to provide some relief.
However, for those with moderate to severe IBS symptoms, medical and psychological treatments are recommended. These treatments usually target specific symptoms, like pain, diarrhea, or constipation, or aim to decrease the triggers, such as stress, that aggravate the symptoms. Further, there is evidence that for some, implementing a special diet such as the low FODMAP diet for a focused period of time can improve aspects like abdominal pain and bloating, and provide direction for potential aggravating foods.
Conventional medical treatment has included fibre supplements, antispasmodics, gut motility agents, and medications that act on biochemicals such as serotonin in the GI tract and central nervous system. Medication decisions are usually guided by the predominant IBS symptoms. At this point, reviews of the effectiveness of the medication treatments have concluded that they are helpful for small subsets of people with IBS but have been disappointing overall in their impact. Newer medications in development are focusing on brain-gut pathways and the microbiome. For the most up-to-date information on medication treatments as they apply to your situation, you are encouraged to discuss the use of these medications with your family doctor.
Psychological treatments, which also target brain-gut connections, have been found to be effective in providing relief of IBS symptoms and reducing the distress and coping difficulties that often occur when dealing with a chronic illness. These psychological therapies focus on ways to decrease stress and cope differently so that the stress does not ‘go to the gut’.
What Psychological Treatments are Effective?
Psychological approaches have been carefully evaluated over the past number of years; Cognitive Behavioral Therapy (CBT) and related therapies, as well as gut-directed hypnotherapy have specifically demonstrated well-established and lasting benefits. These brain gut behaviour therapies are provided by professionals trained in psychological interventions for health problems and can be delivered effectively in person or online. Medication, in contrast, tends to cease to have an effect when patients stop taking the medicine. Some research suggests that the amount of improvement in psychological treatment relates in part to the effort and time the individual contributes to working with the strategies.
Cognitive Behavioural Therapy (CBT) incorporates a number of steps aimed at changing behaviour to improve health and coping. It often involves providing information to ensure a better understanding of the illness (to help with fears and worries), teaching strategies to change thinking patterns that can contribute to strong emotional and physical reactions, teaching skills to deal with challenging or stressful situations that can trigger the gut, and goal setting to establish optimal health habits. CBT typically includes relaxation training.
Mindfulness and Acceptance-based therapies (ACT) are variations of CBT and emphasize learning ways to relate differently to symptoms, find meaning, and engage in valued activities despite the illness, broadening day to day functioning and overall wellness. These therapies may be offered on their own, or strategies from these therapies may be incorporated into CBT for IBS. Emerging evidence shows good effectiveness for those with severe and refractory IBS symptoms.
Gut-Directed Hypnotherapy uses mental imagery and deep relaxation to alter gut-brain communication, reduce unpleasant gut sensations, and reduce stress-related gut activity.
These psychological therapies are recommended by North American and European gastroenterology treatment guidelines for IBS. Cognitive behavioural therapy is the most commonly available type of psychological treatment for IBS in Canada and the United States, although medical hypnotherapy has become more accessible through scientifically evaluated online programs as well as digital apps.
Where Can I Go for More Information?
For more information about irritable bowel syndrome and steps you can take based on these psychological therapies:
- Scarlata, K., & Riehl, M. (2024). Mind your gut: The science based, whole-body guide to living well with IBS. Hachette Book Group.
- Hunt, M. G. (2022). Reclaim your life from IBS: A scientifically proven CBT plan for relief without restrictive diets (2nd ed.). Routledge.
For general information about IBS and similar gastrointestinal disorders please visit the International Foundation for Functional Gastrointestinal Disorders at http://www.iffgd.org or the Canadian Society of Gastrointestinal Research at https://badgut.org/.
You can consult with a registered psychologist to find out if psychological interventions might be of help to you. Provincial, territorial, and some municipal associations of psychology may make available a referral list of practicing psychologists that can be searched for appropriate services. For the names and coordinates of provincial and territorial associations of psychology, go to https://cpa.ca/public/whatisapsychologist/PTassociations/.
This fact sheet has been prepared for the Canadian Psychological Association by Dr. Lesley Graff, Professor and Head, and Dr. Maia Kredentser, Assistant Professor, Department of Clinical Health Psychology, Max Rady College of Medicine, University of Manitoba. Drs. Graff and Kredentser are registered clinical psychologists who work at Health Sciences Centre, Winnipeg, Manitoba and whose research focuses on gastrointestinal disorders and behavioural medicine.
Revised: October 2025
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