Causes of IBS
The exact cause of IBS is unknown – IBS has been linked to food passing through your gut too quickly or too slowly, stress and oversensitive nerves

What are the causes of IBS ?
The exact causes of IBS (Irritable Bowel Syndrome) are still unknown. This is one of the reasons why the NHS often struggles to provide comprehensive support for patients with IBS.
The good news is that there are several areas your GP may not have explored — areas that our specialist IBS clinic can investigate and help with.
A key challenge in treating patients with IBS is that multiple underlying conditions may be driving the symptoms. In fact, no single test can assess all possible root causes at once.
Potential causes of IBS include Small Intestinal Bacterial Overgrowth (SIBO), food intolerances (such as dairy or gluten), Candida overgrowth, parasitic infections, and chronic stress.
Scroll down to learn more about each of these possible causes or contact us for personalised support.
What are the Main causes of IBS?
Food Intolerances may cause symptoms of IBS
We’re seeing an increasing number of patients whose IBS symptoms are linked to food intolerances. The most common culprits include gluten, dairy, and yeast — found in foods like bread, Marmite, beer, and pizza.
Food intolerances can be tricky to identify because reactions are often delayed. You might eat pasta today but not experience symptoms like bloating or pain until several days later.
Other signs of food intolerances include fatigue, skin issues, and joint pain. We offer IgG antibody testing via blood, which has produced excellent results in our clinic.
Is a Fungal Overgrowth - Candida Albicans, the cause of your bloating and fatigue?
Do you experience symptoms such as bloating, sugar cravings, brain fog, fatigue, constipation, diarrhoea, thrush, or fungal toenails?
Candida albicans is a type of yeast that naturally lives in the body. In small amounts, it doesn’t usually cause any problems. However, it can overgrow and proliferate — especially if you’ve taken multiple courses of antibiotics in childhood or consumed a diet high in sugar or yeast. Common foods that may contribute include bread, stock cubes, soy sauce, balsamic vinegar, and alcohol.
This is an area we specialise in, and we’re confident we can help you.
SIBO VS IBS
One of the causes of IBS may be linked to a condition known as Small Intestinal Bacterial Overgrowth (SIBO). This condition is prevalent among IBS patients. While it remains unclear whether SIBO causes IBS, many individuals with IBS test positive for Small Intestinal Bacterial Overgrowth.
The most common symptoms of SIBO include flatulence, bloating, constipation, and diarrhoea. We can test for this at our clinic using a hydrogen breath test.
If you’d like to read an article on SIBO that Victoria Tyler wrote for Positive Health magazine, please visit this link:
Lactose Intolerance and IBS-D
Lactose intolerance is also very common among patients with IBS- particularly with patients who have IBS-D. (Source)
Lactose is a type of sugar that is normally broken down by an enzyme called Lactase.
Typical symptoms of lactose intolerance include wind, gas and diarrhoea soon after drinking a food with large amounts of lactose such as milk. We can also test for this at our clinic.
Can Parasites cause IBS?
Parasites are another common cause of both IBS-D and IBS-C.
Patients typically experience symptoms such as diarrhoea, constipation, gas, abdominal pain, and a gurgling or churning sensation in the gut. More than 30% of our patients have tested positive for a parasite. Testing for parasites is simple and can be done via a stool test.
Parasites are often contracted during foreign travel — with countries like India, Turkey, Greece, Egypt, and Mexico being common sources. However, they can also be acquired within the UK.
Lack of Digestive Enzymes or Stress
If you are lacking the ability to produce and secrete digestive enzymes including stomach acid you may be experiencing feeling of fullness after eating, bloating diarrhea and constipation. You can test for pancreatic enzymes via a comprehensive stool test and our IBS specialists will also recommend pancreatic enzymes to help you break down and absorb your food.
Psychological factors such as stress may also play a part in IBS.
The Real Causes of IBS by Michael Franklin
If you would like to read the cover story article Michael Franklin wrote recently for Positive Health magazine, please click here.