What Are Fodmaps? A Guide To The Low Fodmap Diet & IBS – Fodmap Challenge

FODMAPs stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols and they are short-chain carbohydrates that are resistant to digestion in some people. Research has found that FODMAPs can trigger symptoms of Irritable Bowel Syndrome (IBS) and following a low FODMAP diet can help relieve symptoms of IBS.

 What are FODMAPs? 

  • Oligosaccharides:  Oligosaccharides include both fructans and galacto-oligosaccharides (GOS). It is important to remember that everyone absorbs these poorly. Some people are just able to better tolerate them than others. Fructans mostly come from wheat products and some vegetables, such as onion and garlic. It also includes inulin (a type of fibre), which is often added to yoghurt, and fructo-oligosaccharides, which are found in packaged foods. GOS are found in legumes. The technical names are raffinose and stachyose.
  • Disaccharides: Lactose is a disaccharide that naturally occurs in milk and milk products. All of us vary in the amount of lactose we can digest. As we age, we have less of the enzyme that breaks down lactose, called lactase. Some ethnic backgrounds (such as those of Asian descent) naturally have less lactase and tend to be more likely to have lactose intolerance.
  • Monosaccharides: Fructose is a monosaccharide, which is most commonly in fruit. It’s usually only a problem if the food contains more fructose than glucose, or with excess consumption in a single sitting.
  • Polyols: Polyols includes sorbitol and mannitol. These are naturally occurring in some fruits and vegetables, while maltitol, xylitol, isomalt and polydextrose are used to artificially sweeten food and as food additives. Everyone only partially absorbs polyols.  Some polyols may appear in the ingredients list under their additive number: Sorbitol (420), Mannitol (421), Maltitol (965), Xylitol (967), Isomalt (953) (contains sorbitol and mannitol), and Polydextrose (1200) (10% sorbitol).

What is IBS?

IBS is a functional gastrointestinal disorder characterised by symptoms such as cramping, abdominal pain, bloating, gas, diarrhoea or constipation, or both. Yep, the symptoms of IBS can be on either and both ends of the bowel movement spectrum. Further complicating this chronic condition is that there is currently no known cause or cure. But don’t be disheartened, determining your IBS triggers can help manage the condition for the long term and improve your quality of life.

What causes IBS?

While the cause of IBS is unknown, factors such as stress, change in routine, infection and diet, can trigger an attack.


As FODMAPs travel through the gastrointestinal, they can be poorly absorbed in the small intestine drawing excess fluid into the gut. This can result in diarrhoea for some IBS sufferers. For others, the carbohydrates can moves into the large intestine where they undergo fermentation by bacteria, producing gas. This gas can lead to symptoms including bloating, constipation, flatulence, pain and nausea.

Low FODMAP diet 

Research has found that following a low FODMAP diet can help reduce symptoms of medically diagnosed IBS in some sufferers. However, it’s important to determine which part of the acronym affects you as strictly eliminating all FODMAPs can have adverse impacts on your long term health.

The low FODMAP diet occurs in three phases.

Stage 1: The elimination phase occurs over four weeks, eliminating your intake of high FODMAP foods.

Stage 2: The FODMAP reintroduction phase will reintroduce each FODMAP back into your diet, one at a time, observing your tolerance and whether they trigger your IBS symptoms.

Stage 3: Once you have determined which FODMAPs trigger your IBS, you can tailor your eating habits to avoid only the necessary foods.

The FODMAP Challenge can help guide you through these stages with expert support to help you determine your FODMAP triggers. You’ll get meal plans, recipe ideas, and expert resources to to help you take control of your gut health, improve your symptoms of IBS, and better your quality of life. Sign Up here

FODMAP food list

Once you have determined your FODMAP triggers, this list of low FODMAP foods and high FODMAP foods can help avoid the ones you are sensitive to. Download our list of FODMAP foods here.

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Chloe McLeod

Chloe is one of the most experienced and sought after dietitians in Australia. Her expertise working with individuals with gut issues, food sensitivities and arthritis and autoimmune conditions, particularly those who are wanting to continue to be at the top of their game is unmatched.

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