Understanding Irritable Bowel Syndrome (and how to treat it)

IBS is a complex condition that can significantly affect your health. But, with the right diagnosis and treatment, you will be on your way to restoring your health. 

Irritable Bowel Syndrome or IBS is a condition that affects the colon, characterised by abdominal pain, bloating, diarrhea, constipation and discomfort, among other symptoms.

IBS is a common problem, affecting up to 15% of the world population. In Australia, as many as one in five adults experience IBS-related symptoms at some point of their lives. IBS is also more common in women, who are twice as likely to develop it.

IBS is a serious condition that can impair your everyday functioning, limiting your productivity. It is estimated that people with IBS are three times more likely to develop depression or anxiety1.

IBS is not the same as inflammatory bowel disease (IBD), characterised by chronic inflammation of all or parts of the digestive tract and includes conditions like Crohn’s disease and ulcerative colitis. In contrast, IBS specifically occurs in the colon and does not necessarily involve inflammation.


What causes IBS?


The underlying causes of IBS are not fully understood but the condition is likely to have a genetic basis1-2. It may also be influenced by the composition of your gut microbiota, increased intestinal permeability as well as by environmental factors like diet3, 5, 21-22. Hence, it can be difficult to identify IBS and mainstream medical approaches often struggle to identify and accurately treat this condition. Instead, medications are given to ameliorate specific symptoms, without targeting the root of the problem.[KG1]


Common IBS symptoms


Most people with IBS suffer from chronic diarrhoea or constipation, bloating, and/or gut pain. Many of these symptoms may be more common in women than in men and for women some symptoms may worsen near menstruation. IBS can also lead to depression and anxiety in some people1.


Generally, IBS can be classified into five major subtypes6:

  • IBS-D, characterised by chronic diarrhea
  • IBS-C, characterised by chronic constipation
  • IBS-M, where patients alternate between diarrhea and constipation
  • Post-infectious IBS, this type of IBS occurs after an infection.
  • IBS-U, this is called unspecified IBS, and it applies to people who experience IBS symptoms but do not fit with any of the previous IBS types.


Do you have IBS?


IBS is commonly diagnosed when a patient suffers from two or more IBS-related symptoms. According to current standards, IBS should be considered as a possible diagnosis when a patient has been suffering from recurrent abdominal pain at least three times per month over the past three months4. In addition, the patient must be experiencing improvement of his symptoms with defecation, and/or changes in the consistency and frequency of stools.

However, it can also happen that an entirely other condition, not IBS, is at play. Other conditions, like Small Intestine Bacterial Overgrowth (SIBO) or parasitic infections can produce similar symptoms.

Accurate diagnosis of requires a complete evaluation from a health practitioner. A full medical check-up along with specific tests will help identify what is causing your IBS problems. A test of your gut microbiota might also be performed, as gut dysbiosis and SIBO have been linked to IBS7.

Altogether, these tests are meant to help identify a potential role for other conditions that produce similar symptoms, such as:

  • Coeliac disease
  • Bowel cancer
  • Inflammatory bowel disease
  • Diverticulitis
  • Polyps
  • Small Intestine Bacterial Overgrowth (SIBO)
  • Parasite infections

Once your test results have been assessed, a diagnosis can be made, and a treatment plan can be designed.


Avoiding IBS triggers


While the underlying causes of IBS are not fully understood, we know that certain factors act as triggers in some people. These include,

  • Diet – A low-fibre diet is known to worsen constipation in IBS patients.
    • Recent studies propose following a low-FODMAP diet to reduce symptoms but consult with your healthcare specialist first before embarking on a new diet. More on the FODMAP diet below.
    • Check for food intolerance. If you suffer from lactose, fructose or sucrose intolerance, for example, you may be more likely to develop IBS8-9.
  • Infections – episodes of gastroenteritis (inflammation of the stomach and intestines) can trigger IBS, as well as other infections, such as:
    • Clostridium difficile – Infection by this pathogen can leave patients susceptible to developing IBS10.
  • Medications use – the use of broad-spectrum antibiotics, such as macrolides or tetracyclines, has been shown to be associated with the development of IBS.
    • Excessive use of antibiotics can also have negative effects on the gut microbiota, potentially leading to dysbiosis11.
    • Antibiotics aside, medications such as antacids or painkillers can have negative effects on some IBS-related symptoms, such as constipation or diarrhoea12-14.
  • Stress – people suffering of high levels of stress and / or anxiety are more likely to develop episodes of IBS15-16.



IBS Treatment and cure


There is no simple cure for IBS and accurate diagnosis is key. Treatment for this condition usually involves a combination of medications and lifestyle changes, depending on the underlying problems.

Taking care of the gut microbiota and avoiding episodes of dysbiosis has been shown to have various benefits in gut and overall health17-21. Current research linking the gut microbiota with the development and maintenance of IBS is ongoing and, so far, studies have shown that at least some people with IBS experience gut dysbiosis5, 21. Studies exploring the use of probiotics as treatment for IBS have, so far, obtained mixed results, with only some studies reporting improvements of IBS symptoms, whereas others report no significant effect22-24.

In terms of diet, some IBS patients have obtained benefits from a diet low in Short-chain fermentable carbohydrates (commonly known as FODMAPs). A low FODMAP diet is commonly advocated to help reduce IBS symptoms, and various studies support the benefits of its use in IBS, particularly for symptoms like abdominal pain and bloating25-26.

However, care should be taken before undertaking a low FODMAP diet, as it may cause significant changes in your gut microbiota and may affect other health aspects due to the strict dietary restrictions it involves. For example, a low FODMAP diet may result in low intake of fibre, calcium, iron, zinc, folate, B and D vitamins, and antioxidants27-29.

At the Australian Centre of Functional Medicine, we take a comprehensive approach that includes multiple testing, which will help design a personalised treatment plan.

IBS infographic




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[KG1]Rob, are you happy with this statement?