Do you know that up to 60% of people who have irritable bowel syndrome (IBS) could develop chronic stress, anxiety, and depression?
Irritable Bowel Syndrome (IBS) is a common gastrointestinal disorder characterized by symptoms like abdominal pain, bloating, and altered bowel habits.
People with IBS are struggling with a restricted diet, constant abdominal bloating and pain, diarrhea, constipation, and bathroom urgency.
Moreover, these symptoms may appear unpredictably; imagine rushing to the bathroom right before an important meeting. That's the reality for many IBS sufferers.
While it's not life-threatening as it doesn't cause permanent damage to the intestines, its symptoms can be chronic and significantly impact a person's quality of life.
This article explores the key aspects of IBS, including its causes,gut-brain relation, how IBS affects mental health, and management strategies.
Whether you are newly diagnosed, living with IBS, or seeking ways to improve your digestive health, understanding this condition is the first step toward better management.
What is Irritable bowel syndrome(IBS)?
Irritable bowel syndrome(IBS) is a functional gastrointestinal disorder, meaning it affects how the digestive system works rather than causing structural damage or visible disease.
IBS has three primary types: IBS with diarrhea (IBS-D), IBS with constipation (IBS-C), and IBS with mixed bowel patterns (IBS-M).
The causes of these types are unclear and not specific; many factors could result in IBS.
However, it is often linked to stress, gut microbiome imbalances (living organisms in your gut), and abnormal gut motility (too fast or too slow digestion).
Each cause could have specific symptoms, which also vary from person to person; for example, some people may experience abdominal discomfort while others experience excessive watery stool or bloating during stressful situations(Occhipinti & Smith, 2012).
Researchers found that in primary health care, 12 out of 100 seek treatment for IBS, most of them between 20-40 years old.
Among these patients, women form the majority and usually come with abdominal pain and constipation, unlike men who are less and usually report diarrhea. Researchers also found that IBS decreases with age, explaining why most patients are under 40 (Patel & Shackelford, 2025).
Breakdown of the most common known causes
A system review of 139 studies suggests these causes, and the researcher explains the disease as a cluster of symptoms resulting from diverse pathologies(Chey et al., 2015).
Problems with gut movement (food moving too fast or too slow).
Increased gut sensitivity(certain foods trigger symptoms).
Brain-gut communication issues (signals between the brain and gut not working correctly).
Stress and mental health factors.
Other causes suggested when doctors examine the digestive system tissue of people with IBS, they find signs of inflammation and changes in specific cells and nerves(Patel & Shackelford, 2025).
Chronic inflammatory cells (suggesting mild ongoing inflammation).
Mast cells (immune cells that may contribute to gut sensitivity and pain).
Enteroendocrine cells (which help regulate digestion and gut movement).
Enteric nerves (nerves in the gut that can affect sensation and motility).
Researchers found that people with IBS-D (diarrhea-predominant IBS) have a higher number of immune cells (T-lymphocytes) in their guts than those with IBS-C (constipation-predominant IBS).
They also find increased nerve fibers and specific substances (Patel & Shackelford, 2025). The increased immune cells and nerve fibers alongside other substances contribute to IBS.
The most common substances that play a significant role in IBS are:
1. Serotonin: a neurotransmitter that regulates mood, digestion, and gut movement.
About 90% of the body's serotonin is found in the gut, where it helps control digestion and bowel movements.
It regulates gut motility (how food moves through the intestines).
Too much serotonin can cause diarrhea (IBS-D), while too little can lead to constipation (IBS-C).
2. Substance P: A neurotransmitter involved in pain signaling and inflammation.
In the gut, it increases pain sensitivity, making IBS patients more likely to feel discomfort.
It also stimulates muscle contractions, which can lead to diarrhea or cramping.
The Gut-Brain Connection
Your digestive system communicates with your brain through a network that includes nerves, hormones, and immune signals.
This network, called the gut-brain axis, influences your appetite, mood, emotions, and cognitive function.
It aims to maintain digestion and overall body balance(Carabotti et al., 2015).
Abnormality in the Gut-Brain Axis could result in IBS as follows:
Hormonal System (HPA Axis - Stress Response):
When you feel stressed, your brain stimulates the adrenal gland to release cortisol (the stress hormone) to cope with environmental demands.
This cortisol hormone impacts your digestive function by affecting digestive cells, nerves, immune cells, and muscle activity in the intestines. Thus, stress is a major trigger for IBS symptoms(Tsigos & Chrousos, 2002).
Gut Microbiome:
Gut bacteria are found throughout the digestive system and play a significant role in producing hormones like serotonin, which regulate bowel movement and enhance mood.
As I mentioned above, the cortisol hormone affects many cells in your digestive system. Therefore, imbalances in gut bacteria by cortisol or other factors may lead to IBS and contribute to anxiety and depression(Foster & McVey Neufeld, 2013).
How IBS Affects Mental Health
A study analyzed ten different studies comparing patients with IBS to healthy individuals. The results indicate that patients with IBS experience higher levels of anxiety and depression compared to healthy individuals. (Fond et al., 2014).
The study found that up to 60% of IBS patients experience major psychological issues, including anxiety, depression, and somatization (physical symptoms caused by stress).
This result confirms that abnormality in Gut-Brain communication ultimately impacts mental health.
For this reason, consider seeking mental health therapies that may help improve your IBS symptoms and quality of life.
Don't only focus on managing the physical symptoms of IBS; your mental health plays a significant role in IBS.
How Mental Health Affects IBS
The gut-brain connection explains how mental health issues could affect IBS; for example, when you are stressed out, your body secretes the stress hormone, and this stress hormone is the primary trigger for IBS.
Key Effects of Stress Hormone on IBS:
Increases gut sensitivity and motility:
High cortisol increases colon sensitivity, leading to abdominal cramps and changing bowel movements(Ibs, 2022).
Weakens gut lining (increases permeability):
Your gut lining tissue plays a role in defense against harmful bacteria. In chronic stress, this lining becomes weak. It increases permeability, allowing harmful bacteria and substances to pass through the lining more efficiently in your blood. Subsequently, this results in inflammation(Chang, 2011).
Activates immune system responses in the gut:
When harmful bacteria and substances migrate through the weak gut lining, your immune system tries to eliminate these unknowing substances and bacteria, leading to inflammation that worsens IBS symptoms(Chang, 2011).
Alters digestive microorganisms and nervous system function:
Cortisol affects the normal function of gut microorganisms in hormone secretion and nerve fibers, which causes a higher pain sensation and changes in bowel movements (Irritable Bowel Syndrome, 2022).
Triggers flare-ups and worsens symptoms:
Flare-ups mean sudden worsening of IBS symptoms, and this is mainly related to stress, which is the primary trigger of IBS symptoms (Stress Triggers Ibs Symptoms, Impacts Quality of Life More than Diet, Study Finds, 2024).
The Treatment of IBS and Mental Health Together
The treatment of IBS mainly depends on managing stress. Many traditional methods fail to manage stress, so people are looking for non-pharmacological approaches such as Cognitive Behavioral Therapy, hypnotherapy, Dietary Changes, and Exercise.
Follow up with your doctor to determine what fits you. However, here are some fundamental steps to try to implement them:
Stress Management:
Understanding that stress isn't just in your mind but also in your gut is the first step toward fewer flare-ups, discomfort, and frustration. Psychological therapists could help you determine a strategy to manage stress, like cognitive-behavioral therapy(CBT) and gut-directed hypnotherapy.
Dietary Changes:
I know sticking with consistent food is frustrating, but cutting that good food will make you healthier.
One of the foods you should restrict is FODMAPs. This rich carbohydrate diet is poorly absorbed in the small intestine, usually resulting in bloating, gas, loose stool, constipation, and stomach pain.
Low-FODMAP diets are a proven way to reduce IBS symptoms; a study published in the Journal of Gastroenterology found that patients who followed them experienced significant improvements in their digestive symptoms and overall well-being(Böhn et al., 2015).
Exercise and Lifestyle Adjustments:
Regular physical activity and adequate sleep are known to enhance mood. They also reduce gut sensitivity and bloating, improve digestion and bowel movements, and lower stress(Johannesson et al., 2015).
Pharmacological Advances in IBS Treatment
Researchers link mental health issues like anxiety and depression to serotonin abnormality in IBS, and several serotonin-based drugs showed efficacy in the treatment of IBS(Tack et al., 2006).
Here are the most commonly used drugs and newer drugs:
1. Serotonin-based medications (Help regulate gut motility and sensitivity)
2. 5-HT4 Agonists (New drugs in trials, showing promise for symptom relief)
3. Ramosetron (Used for IBS-related visceral pain)
4. Antidepressants & Antipsychotics (Help manage stress-related symptoms)
IBS is not just a digestive issue—it's a complex condition influenced by stress, gut health, and the brain. While it doesn't cause permanent damage, its unpredictable symptoms can disrupt daily life, impact mental health, and lead to frustration.
Managing IBS isn't just about avoiding certain foods or taking medication; it requires a holistic approach that considers both physical and mental well-being.
By understanding the gut-brain connection, you can control your symptoms. Managing stress, adjusting your diet, staying active, and exploring therapies like CBT or gut-directed hypnotherapy can make a significant difference.
If IBS affects your quality of life, don't ignore it—seek professional guidance and the right strategy.
Your health is in your hands, and small changes can lead to significant improvements.