FODMAPs explained

FODMAP is term coined by researchers at Monash University in Melbourne to describe a group of sugars that can be poorly absorbed, contributing to the onset of symptoms of irritable bowel syndrome (IBS).  The FODMAP acronym stands for:

Fermentable Oligo-saccharides Di-saccharides Mono-saccharides And Polyols

You can see why the acronym was needed…

So, these FODMAP sugars include:

  1. Fructose – found in fruit, honey, juices.
  2. Lactose – found in milk and milk products.
  3. Sugar polyols such as sorbitol and mannitol – found in some fruits and vegetables and as artificial sweetner.
  4. Fructans – found in wheat, rye, onions, garlic.
  5. Galacto-oligosaccharides (GOS) – found in legumes such as chickpeas, kidney beans or baked beans.

When these sugars are poorly absorbed in the small intestine increased water can be drawn into the gut, which can result in diarrhoea in some people.  For others, the sugars travel to the large intestine where they are fermented by bacteria, producing gas.  This gas can lead to bloating, flatulence, pain and nausea.  It can also cause bowel movement to slow down which can contribute to constipation.

“I have those symptoms.  How do I know if FODMAPS are causing them?”

Your first port of call should always be a medical practitioner or accredited practicing dietitian.  There is no point trying to guess which foods may be contributing to your symptoms; you could spend a lifetime doing this.

Your doctor or dietitian can order a variety of tests to help figure out the cause of your symptoms.  It is important that you have blood tests to rule out coeliac disease or gluten intolerance.  Coeliac disease is a serious genetic condition that requires a life-long gluten-free diet, and is very different to FODMAP malabsorption.

Hydrogen and methane breath tests can be done to check if you are malabsorbing fructose, lactose and sorbitol.  They simply involve drinking a measured amount of a sugar solution and breathing into a bag approximately every 30 minutes over the next 2-3 hours.  The amount of hydrogen and methane is measured in each breath sample.  A rise in these gases indicates the sugar has been malabsorbed and that you could benefit from a low FODMAP diet.

If your tests do come back showing FODMAP malabsorption, a dietitian can guide you through the low FODMAP diet.  It may take some adjustment in the foods that you choose and the way that you cook, but how great it is to have some relief from IBS.