Irritable Bowel Syndrome (IBS) is a common gut disorder that affects how the gastrointestinal tract functions. It is an issue for 7-15% of the population.
What are the symptoms of IBS?
A formal diagnosis should be made by a Doctor and IBS is typically indicated by two or more of the following symptoms
✔️ Abdominal pain
✔️ Excessive wind
✔️ Bloating
✔️ Change in bowel frequency (going a lot or not going much)
✔️ Change in bowel consistency (very runny or very hard stool)
How is IBS Diagnosed?
There is no specific laboratory or imaging tests to diagnose irritable bowel syndrome, rather a diagnosis is made based on the presence of certain symptoms. Your Doctor may use the Rome IV criteria to diagnose you, which, in simple terms means;
The following symptoms are present at least 1 day/week for at least the last 3 months;
✔️ Abdominal pain associated with going to the toilet (which either increases or decreases pain)
✔️ Change in stool frequency (going more or less than usual)
✔️ Change in the appearance of stool (runny or very hard stool)
Other symptoms which may also be present are;
✔️ Feeling sick
✔️ Bloating
✔️ Cramps
✔️ Excess wind
Subcategories of IBS
IBS can also be classified with subcategories, depending on the most dominant symptoms;
- Diarrhoea predominant (IBS-D)
- Constipation predominant (IBS-C)
- Mixed/alternating (IBS-M/IBS-A) (alternating between diarrhoea and constipation)
IBS symptoms can be very upsetting. Being uncomfortable, in pain, anxious about your gut, or worried about getting to the toilet in time, can really impact your quality of life. But, be reassured that, while these symptoms can be uncomfortable and painful, IBS doesn’t damage your digestive tract or raise your risk for colon cancer or other bowel related diseases.
What Causes IBS?
The gut is complex, which means both the causes and symptoms of IBS are complex and can vary from person to person. However, research suggests that several key factors may contribute to the condition.
Abnormal Intestinal Muscle Function
In a normal digestive system, the muscles in the intestine contract and relax in a rhythmic way, helping food and waste move through. In IBS, this process can become dysregulated, leading to:
✖️ Overactive muscles – Food moves too quickly through the intestine, reducing water absorption and causing diarrhoea.
✖️ Slow-moving muscles – Food takes longer to pass through, allowing too much water to be removed, leading to constipation.
✖️ Muscle spasms – These can cause cramping, bloating, and trapped gas, resulting in discomfort and wind.
While the exact cause of these muscle irregularities isn’t fully understood, research suggests it may stem from disruptions in gut-brain communication, affecting how the intestine functions.
Gut Hypersensitivity
Heightened gut sensitivity is another potential cause of IBS. People with IBS may produce more gas than usual, which can make the gut more reactive and sensitive to normal digestive processes. When the digestive system is under strain like this, even minor triggers can lead to discomfort and pain that wouldn’t normally be an issue. For some, this increased gut sensitivity begins after a bout of gastroenteritis (a stomach infection). The initial inflammation from the illness may lead to long-term hypersensitivity, making the gut more prone to irritation and discomfort.
Gut Microbiome
The beneficial bacteria in the gut play a crucial role in overall health and well-being. In people with IBS, the gut microbiome may be imbalanced—either with an overgrowth of certain bacteria or a deficiency of others—potentially disrupting digestion and gut function.
Stress and the Gut-Brain Connection
The gut and brain are deeply connected, meaning stressful life events can trigger or worsen IBS symptoms. Psychological stress—whether from work, relationships, or daily challenges—can manifest as physical symptoms in the gut.
Stress and anxiety can:
✔ Disrupt digestion by slowing down intestinal movement
✔ Increase muscle cramps, gas, and gut sensitivity
✔ Alter the gut microbiome, potentially leading to imbalances
✔ Weaken the gut barrier, increasing intestinal permeability (leaky gut)
Additionally, worrying about IBS symptoms can create a cycle, where stress worsens symptoms, leading to more anxiety and ongoing discomfort.
Body Chemicals and Hormones
The gut is home to a complex enteric nervous system, containing over 600 million neurons that regulate digestion by releasing hormones and neurotransmitters. These chemical messengers play a crucial role in gut function, helping to control movement, sensitivity, and overall digestive balance. When this system is disrupted or out of balance, it can lead to irregular digestion, heightened gut sensitivity, and IBS symptoms. Maintaining a healthy gut environment supports the proper release of these essential chemicals, promoting smoother digestion and overall well-being.
Food intolerances
If the gut becomes unsettled (because of any of the reasons above), it can become very sensitive to food triggers. In an already irritated digestive system, specific foods may worsen symptoms.
Please be aware that occasionally, symptoms may coexist with those of other serious illnesses. Talk about your symptoms with your Doctor, particularly if they include blood in your stools or unexplained weight loss. IBS should not be self-diagnosed; instead, talk to your Doctor about your symptoms.
Check out our article on TREATING IBS for research based solutions.
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