What is the root cause? It depends on the individual person. IBS is a multi-factorial disorder and it can have multiple root causes. They may include:
- Eating highly processed, low-fibre diet
- Low water intake
- Altered gut flora (dysbiosis): Dysbiosis happens when the bad bugs in your gut take over. People with imbalance of GI bacteria are more prone to symptoms of IBS (2). Dysbiosis is common due to overuse of antibiotics, as well as alcohol, high sugar diet and stress. Healthy gut flora contributes to production of amino acids, certain vitamins, as well as neurotransmitters, such as your happy hormone serotonin.
- Food sensitivities and intolerances: IBS sufferers often report sensitivity to certain foods, commonly to certain carbohydrates (especially foods containing gluten), as well as certain fats (3,4). Lactose intolerance is also a common cause of IBS and it can be diagnosed by simple breath test.
- Stress: Those under a lot of stress, as well people suffering from anxiety and depression are more prone to experience IBS symptoms (5). Our gut is also called a “second brain” and many IBS sufferers link their emotions and stress levels to worsening of the symptoms.
- SIBO – Small Intestinal Bacterial Overgrowth: a condition characterised by abnormal overgrowth of bacteria in the small intestine. It is estimated that up to 84% of IBS sufferers have SIBO (6). Most of the gut bacteria is meant to be located in the large intestine, where they help to break down food, synthesize vitamins, and eliminate waste. In SIBO these healthy bacteria colonise the small intestine. People with SIBO will have excess levels of hydrogen, methane or both, and it can be diagnosed by hydrogen and methane breath test (7).
- Increased intestinal permeability (“leaky gut syndrome”): Studies have also shown an association between IBS and increased intestinal permeability (8). The gut lining is like a net with extremely small holes to allow certain substances to pass through. In a leaky gut those holes become bigger allowing undigested food particles, proteins, toxins and bad bacteria to pass through. An unhealthy gut lining makes it harder for digestion to work at optimal level.
- Gut infections: Certain gut infections have been associated with IBS. For example intestinal parasites such as Blastocystis hominis and Dientamoeba fragilis, as well as food poisoning caused by Campylobacter bacteria may trigger IBS (9,10).
- Lack of exercise: Exercise is crucial for the functioning of your digestive system. If you are inactive, so will be your digestion. On the other hand, if you are active, your digestion will follow.
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