FODMAP explained

FODMAPs are a specific types of carbohydrates known as short-chain carbohydrates. For certain people, the consumption of short-chain carbohydrates can lead to a variety of uncomfortable and embarrassing symptoms, including bloating, distended abdomen, flatulence, cramps, diarrhoea and constipation.

In such individuals, the short-chain carbohydrates or FODMAP foods are poorly digested in the small intestine. The undigested food particles travel onto the large intestine, where the gut bacteria begin the process of fermentation. During this process water is drawn into the large intestine and carbon dioxide, hydrogen and methane are produced. It is the production of these gases, which results in uncomfortable symptoms.


There are four main groups of carbohydrates or saccharides (sugars) as they are known, which are referred to within the term ‘FODMAP’, oligosaccharides, disaccharides, monosaccharides and polyols. The acronym FODMAP is explained below:

  • Fermentable – can be fermented by bacteria in the large intestine

  • Oligosaccharides – ‘oligo’ means few, sugar molecules in a chain

  • Disaccharides – ‘di’ means two, a double sugar molecule

  • Monosaccharides – ‘mono’ means one, a single sugar molecule

  • And Polyols – sugar alcohols

You may recognise the names of the saccharides, which fit into the different groups:

Where is this found? Oligosaccharides Fructans Vegetables and grains Galactans Legumes Disaccharides Lactose Milk and milk products Monosaccharides Fructose Fruits and vegetables Polyols Sorbitol Artificial sweeteners Mannitol Artificial sweeteners

Sensitivity Vs Intolerance

The number of fructans, galactans, lactose, fructose, sorbitol or mannitol in a food item often varies. For example, apples would be classed as a high-FODMAP fruit whereas strawberries would be classed as a low-FODMAP food. With some items a small portion can be tolerated whereas a large portion will produce a high-FODMAP load.

Individuals who are sensitive or intolerant to FODMAP foods are not necessarily intolerant to all of them. It is a case of understanding those that cause discomfort and symptoms through a process of elimination.

It is important to know that being intolerant or sensitive to certain FODMAP foods may or may not coexist alongside IgG intolerance, and this is a highly individual matter. If you do wish to consult our Lifelab Testing nutrition team on your results, FODMAP foods may be an area we discuss with you.

Sian Baker DipION mBANT mCNHC

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Sian Baker DipION mBANT mCNHC

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