FODMAPs are short chain carbohydrates that are poorly absorbed in the small intestine. The term FODMAP is an acronym, derived from “Fermentable, Oligo-, Low fodmap diet list pdf-, Mono-saccharides And Polyols”.
Prior to the formation of the FODMAP concept, diet was seldom used as first line therapy for management of IBS and other FGID. Over many years, there have been multiple observations that ingestion of certain short-chain carbohydrates, including lactose, fructose and sorbitol, fructans and galactooligosaccharides, induced IBS-like symptoms. These studies also showed that dietary restriction of short-chain carbohydrates was associated with symptom improvement in some people with IBS. Firstly, being small molecules and either poorly absorbed or not absorbed at all, they drag water into the intestine via osmosis.
The dual actions of these carbohydrates cause an expansion in volume of intestinal contents, which stretches the intestinal wall and stimulates nerves in the gut. It is this ‘stretching’ that triggers the sensations of pain and discomfort that are commonly experienced by IBS sufferers. The FODMAP concept was first published in 2005 as part of a hypothesis paper. In this paper, it was proposed that a collective reduction in the dietary intake of all indigestible or slowly absorbed, short-chain carbohydrates would minimise stretching of the intestinal wall.
At the time, there was no collective term for indigestible or slowly absorbed, short-chain carbohydrates, so the term ‘FODMAP’ was created to improve understanding and facilitate communication of the concept. The low FODMAP diet was originally developed by a research team at Monash University in Melbourne, Australia. The Monash team undertook the first research to investigate whether a low FODMAP diet improved symptom control in patients with IBS and established the mechanism by which the diet exerted its effect. Monash University also established a rigorous food analysis program to measure the FODMAP content of a wide selection of Australian and international foods.
Such luminal distension may induce pain, a sensation of bloating, abdominal distension and motility disorders. Therapeutic approaches seek to reduce factors that lead to distension, particularly of the distal small and proximal large intestine. The small molecule FODMAPs exhibit these characteristics. Poor absorption of most FODMAP carbohydrates is common to everyone.