The month of April is recognised as IBS awareness month. We’ve asked Kirstin Kadé from Taste and See blog, an MSc Nutrition student and IBS sufferer herself, to dig into the facts and fiction that might be circulating online when it comes to tackling this troublesome syndrome.

We’ve read a bit about irritable bowel syndrome (IBS) and learnt about some really practical tips how to best manage it earlier this month. In this article Kirstin will tackle six common IBS myths and share evidence-based information to help you better understand the condition.


#1 – IBS isn’t a big deal

Although early theories around IBS suggested that it was a psychosomatic or mental disorder, we know know that it is actually a functional gut disorder that affects the way that muscles of the gastrointestinal tract (GIT) work, and how signals between the GIT and the brain are sent.

The pain and discomfort caused by IBS is highly variable between people and even within the same person on different days and times. Some people find it to be slightly irritating, whilst others can find IBS symptoms to be rather debilitating. This can make symptom management and life in general pretty difficult.

In the United States it is estimated that IBS accounts for 3.1 million ambulatory care visits and 5.9 million prescriptions each year, costing the healthcare system over $20 billion dollars [1].

IBS is a very real problem that can significantly reduce health-related quality of life, and has an impact on work, social activities, and the ability to live life without fear of having to find the nearest toilet.


#2 – There is no concrete diagnosis for IBS

Although there are no specific diagnostic tests to confirm IBS, it is diagnosed according to strict criteria known as the Rome IV Criteria. These updated guidelines are based on current available evidence and are updated as new evidence emerges[2]. For an IBS diagnosis, these criteria require that patients have experienced recurrent abdominal pain on average at least 1 day per week during the previous 3 months that is associated with ≥2 of the following:

  • Related to defecation (either increased or unchanged)
  • Associated with a change in stool frequency
  • Associated with a change in stool form or appearance

There are three main types of IBS, namely IBS-C (with constipation), IBS-D (with diarrhoea), and IBS-M (with mixed bowel pattern), which can change throughout the life of an IBS patient.

Finally, it’s really important that screening takes place to rule out other concerning symptoms, other GIT disorders, and infections before a diagnosis can be made. It is also very important that this is done by a qualified healthcare professional, and that you do not self-diagnose.


#3 – The low FODMAP diet should be followed for life

Several well-designed studies have consistently shown the value of a low FODMAP (Fermentable Oligosaccharides, Disaccharides, Monosaccharides And Polyols) diet in reducing symptoms in IBS patients[3]. FODMAPs are found in many different types of foods, from onions and leeks, to dairy, apples, and wheat. Consumption of some FODMAPs can lead to increased small intestinal and colonic water secretion and fermentation, which can trigger unpleasant IBS symptoms[1].

The FODMAP diet includes a period of full exclusion followed by the gradual reintroduction of FODMAPs once at a time in order to figure out what foods trigger IBS symptoms. It is really important that the FODMAP diet is done alongside a qualified nutrition professional who knows what they’re doing, and that the exclusion stage isn’t be followed for life.

To date the long-term effects of a low FODMAP diet are unknown, and it is not recommended to follow the stringent restrictive FODMAP restriction following the re-introduction and testing phase due to risks of inadequate nutrient and fibre intake, and potential adverse effects that may result from altered gut microbiota[3].


#4 – IBS is only triggered by food

Although most IBS sufferers identify foods as a trigger for unpleasant symptoms, it is not the only trigger worth noting. IBS has actually been shown to be influenced by various different factors including alterations in the gut microbiome, intestinal permeability, gut immune function, gut motility, visceral sensitivity, brain-gut communication, and psychosocial status[1].

Environmental factors such as early life stressors, antibiotic use, GI infection, and food intolerances may also play a role in its development[1]. Psychological stress is another important trigger that is often overlooked in IBS patients, and in fact various ‘psychological therapies’ such as cognitive behavioural therapy, hypnotherapy, and various forms of psychotherapy have been shown to be very beneficial for managing IBS symptoms[1].


#5 – IBS is just a reaction to gluten. Cut out gluten and you’ll be fine!

Although some of the symptoms experienced by IBS sufferers are prevalent in patients with coeliac disease, these two conditions are not the same. Having said that, IBS sufferers often report intolerances or sensitivities to specific foods that trigger flare-ups. The effect of gluten was assessed by Biesiekierski et al. in 2011 using a randomised, double-blind, placebo-controlled trial in 34 IBS patients[4].

During a 6 week intervention gluten-containing foods were shown to significantly affect IBS symptoms including abdominal pain, bloating, and stool consistency. Although at the time, the results of this study led some to conclude that gluten was a primary cause of IBS symptoms, there were a number of factors that weren’t properly controlled for.

A follow-up study by the same research group better controlled for other components of wheat, including fructans (a group of fermentable, poorly absorbed, short-chain carbohydrates)[5]. They found that in a group of 37 IBS patients with wheat sensitivity, symptom relief was more closely linked to exclusion of these poorly absorbed short-chain carbohydrates than gluten[5].

It is thus likely that the widespread ‘anti-gluten’ messages portrayed by the media and influential personalities has contributed to the perceived negative effects of gluten-containing foods rather than gluten itself.


#6 – Just eat more fibre

Although GPs have been advising patients to eat more fibre as a means of controlling IBS symptoms for years, there is actually limited evidence surrounding increasing fibre consumption or supplementation for functional bowel disorders[6].

It is very important to assess the type of fibre and its associated characteristics in IBS patients, as different types of fibre can affect symptoms in each IBS subgroup differently[6]. Certain types of fibre undergo partial or total fermentation in the colon, leading to the production of short-chain fatty acids and gas that in turn can affect GI function and uncomfortable sensations[6].

A large systematic review and meta-analysis evaluated 14 randomised controlled trials to assess the benefits of using fibre in treating IBS[7]. The authors found that there was a significant benefit to using soluble fibre, such as psyllium, in patients with IBS-C whilst insoluble wheat bran was not significantly beneficial[7].

When using fibre as a first-line therapy, it should be started at a lower dose that is gradually increased to a total daily intake of 20-30g so that symptoms can be managed and assessed along the way.



[1] Chey WD, Kurlander J, Eswaran S. Irritable Bowel Syndrome A Clinical Review. JAMA. 2015 Mar 3;213(9):949-58.

[2] Schmulson MJ, Drossman DA. What is New in Rome IV. J Neurogastroenterol Motil. 2017 Apr;23(2):151-63.

[3] Nanayakkara WS, Skidmore PML, O’Brien L, Wilkinson TJ, Gearry RB. Efficacy of the low FODMAP diet for treating irritable bowel syndrome: the evidence to date. Clin Exp Gastroenterol. 2016 Jun 17;9:131-42.

[4] Biesiekierski JR, Newnham ED, Irving PM, Barrett JS, Haines M, Doecke JD, Shepherd SJ, Muir JG, Gibson PR. Gluten Causes Gastrointestinal Symptoms in Subjects Without Celiac Disease: A Double-Blind Randomized Placebo-Controlled Trial. Am J Gastroenterol. 2011 Jan;106:508-14.

[5] Biesiekierski JR, Peters SL, Newnham ED, Rosella O, Muir JG, Gibson. No Effects of Gluten in Patients With Self-Reported Non-Celiac Gluten Sensitivity After Dietary Reduction of Fermentable, Poorly Absorbed, Short-Chain Carbohydrates. Gastroenterol. 2013;145:320-8.

[6] Eswaran S, Muir J, Chey WD. Fiber and Functional Gastrointestinal Disorders. Am J Gastroenterol. 2013 Apr;108:718-27.

[7] Moayyedi P, Quigley EMM, Lacey BE, Lembo AJ, Saito YA, Schiller LR, Soffer EE, Spiegel BMR, Ford AC. The Effect of Fiber Supplementation on Irritable Bowel Syndrome: A Systematic Review and Meta-analysis. Am J Gastroenterol. 2014 Jul;109:1367-74.