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How A FODMAP Diet Can Help To Improve The Symptoms Of Irritable Bowel Syndrome

FODMAP Diet (620x930)

Developed by a team of dietitians and gastroenterologists at MONASH University in Victoria, a low FODMAP diet can help to improve symptoms of Irritable Bowel Syndrome (IBS). The team showed that limiting a series of short-chain carbohydrates from the diet can reduce symptoms of bloating, wind, and diarrhoea (all symptoms of IBS).

Is IBS Considered A Serious Problem Or Is It A “Nothing” Diagnosis?

A lot of clients come to SS Diets and say, “I had a colonoscopy (because something isn’t right) and the doctor said there’s nothing wrong with me. They’ve told me I just have IBS. Something definitely doesn’t feel right though. There IS something wrong. Can you help?”

We understand both sides of this conversation, the patient’s side and the doctor’s side. The patient is distressed because their functional digestive system is not working properly. They get symptoms of diarrhoea, constipation, bloating, excessive wind and lower abdominal cramping which is “not normal”. We use inverted commas here, ‘cause, yep, it is normal that our body gurgles, expands and toots. These are all normal parts of digestion. However, when it’s uncontrollable (yep, adult accidents), excessive or emotionally distressing then we classify that as not normal.

Comparatively, your doctor is looking for something he or she can see. They’re looking for a disease process. Something like Crohn’s, Ulcerative Colitis, bowel cancer, a tumour or Coeliac Disease. So, they are right – there is no disease process they can see or detect with scans, biopsies or blood tests. Try to remember: THIS IS A GOOD THING! Your symptoms are not caused by a tumour or aggressive disease state.

IBS is defined as a state of longer than 30 minutes of abdominal pain related to a change in bowel frequency and form (appearance), more than once per week, for longer than 3 months (in the absence of any medical cause). So, when you actually understand the criteria, maybe, in fact, your doctor is correct, rather than dismissing your symptoms?


FODMAPs (Fermentable, Oligo-, Di- Mono-Saccharides and Polyols) are a group of molecules naturally occurring in a specific range of foods. Our foods are made up of a combination of very small molecules. In chemistry, we call them chemicals but they’re not chemicals like when you think about food with “added chemicals”. Most of them fall into the sugar category (saccharide means sugar). Again though, these are not “added sugar” or sugar, as in your sugar bowl at home.

There are 6 different molecules that make up the FODMAP family: Sorbitol, Mannitol, Fructose, Lactose, Fructans and Galacto-Oligo-Saccharides (GOS). The clever dietitians at MONASH University have been able to show those molecules cause fluid and gas changes within your small and large bowel that lead to the symptoms we mentioned above. So reducing them in your diet will address IBS symptoms; in roughly 70% of patients (that’s what the research tells us)

The List Of FODMAPs Don’t Make Any Sense.

We hear this a lot. That there must be some mistakes in the lists of foods that are high and low in FODMAPs. Trust us, there are no errors. Understanding food chemistry (molecules) is a lot more complicated than most people realise. For example, honey is on the high list, whereas maple syrup and golden syrup are on the low list. To most people these foods are interchangeable but they’re not the same food, made up of the exact same molecules. Yes, they’re both high in sugar but they’re made up of different types of sugars. Honey is high in Fructose, whereas maple and golden syrups are high in Sucrose (which is NOT a FODMAP family member).  So, you can see, without understanding the science behind the low FODMAP diet, of course, the food lists don’t make sense to most people.

How Does A Low FODMAP Diet Work?

The low FODMAP diet is not a quick fix. It’s something you need to invest time into and be able to be at least moderately compliant with. You need to be able to remove the 6 molecules from your diet for on average 4 to 6 weeks and very occasionally up to 10 weeks. We DO NOT suggest starting it before a holiday or major life event (such as a wedding, holiday or around Christmas time). It also doesn’t work if you just do it say, Monday to Friday and then not worry about it on the weekend.

This process generally ends with around 70% of clients who have shown reduced symptoms. The next step is to start the challenge process for these. It’s unlikely that you’ll react to all six of the FODMAP molecules but certainly possible there are 2 or 3 that are problematic. So, we systematically re-introduce them one by one to try and figure out which one caused the problem.

Can A Dietitian Fix An Intolerance?

At the time of writing the answer is no. There is no concrete evidence of any treatment for a molecule intolerance. The only strategy we have is to avoid that molecule that naturally occurs in a certain group of foods. This is how a low FODMAP diet can help to improve symptoms of Irritable Bowel Syndrome. Having said that, note that there’s also no research that suggests if you continue to eat that food and put up with the symptoms you’re doing your body any harm at all. It’s just unpleasant. This is in stark contrast to something like coeliac disease, whereby eating gluten will lead to medical complications including several types of cancer, osteoporosis and infertility.

Need help? 

We recommend only engaging an Accredited Practising Dietitian who is ideally credentialed by MONASH University. Luckily, at SS Diets we have 4 dietitians who are FODMAP certified.

If you’d like further help with any of this, get in contact with the team at SS Diets. Click to book or send an enquiry.