FODMAPs are certain types of carbohydrates known as short-chain carbohydrates. For certain individuals, the consumption of short-chain carbohydrates can lead to a variety of 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. In 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.