FODMAPs are short-chain carbohydrates that are poorly digested in the small intestine. FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides and polyols - how’s that for a mouthful? No wonder we call them FODMAPs.

Fermentation in the gut is a normal part of the digestive process. But many IBS sufferers “feel” when trouble is brewing, especially when they eat a diet high in FODMAPs.

Oligosaccharides (Greek word meaning a few sugars) are made up of a number of sugar molecules. Oligos are hard to digest, with 90% bypassing the small intestine and heading straight to the colon. Much loved oligos include onions, garlic, leeks and legumes. 

Disaccharides are getting easier & easier to avoid. Disaccharides are simple carbohydrate molecules, such as lactose, sucrose & maltose. Lactose is commonly found in dairy products. Lactose malabsorption occurs when the body doesn’t produce enough of the enzyme lactase needed to break down the sugar molecules. Lactose that isn’t absorbed in the small intestine attracts water into the bowel and allows fermentation to occur in the large intestine. This causes diarrhoea, bloating and abdominal cramping.

Monosaccharides are the sweetest of them all...fructose! Monosaccharides are simple sugars, the most basic form of carbohydrates. The most common type is fructose, also known as fruit sugar. It can be malabsorbed, which draws water into the gut and causes motility problems such as diarrhoea.

Polyols are slowly absorbed, but quickly fermented. Polyols are sugar alcohols. They occur in many fruits and vegetables. Polyols provide sweetness. They are absorbed through pores in the lining of the small intestine. Foods high in mannitol and sorbitol often warn of a laxative effect. This is caused by poor absorption in the small intestine, contributing to abdominal pain, bloating and altered bowel movements.