What is a low FODMAP diet?

GrainsIf you've ever suffered from irritable bowl syndrome (IBS), you'll quite possibly have heard of the low FODMAP diet, which cuts out certain carbohydrates for a period of time to reduce or even eliminate symptoms. IBS is a chronic, relapsing and often life-long condition, and symptoms include abdominal pain, bloating and a change of bowel habit. More than four million people in the UK suffer from IBS and people visit their GP between three to ten times for help. There is a tendency to prescribe medication first to help manage symptoms, and GPs spend 14% of their budget on this. But what about the role of diet in treatment? Research shows that up to 86% of people who follow a low FODMAP diet notice a significant improvement in symptoms.

What are FODMAPs?
The catchy acronym stands for fermentable oligosaccharides, disaccharides, monosaccharides and polyols, which are more commonly known as carbohydrates. These can be further divided into five groups called fructans, galacto-oligosaccharides, lactose, excess fructose and polyols. The diet originated in Australia and has been adapted for the UK by researchers at Kings College, London. In essence, FODMAPs are different carbohydrates found in a wide range of foods including onions, garlic, mushrooms, apples, lentils, rye and milk. These sugars are poorly absorbed and pass through the small intestine and enter the colon, where they are fermented by bacteria. Gas is then produced, which stretches the sensitive bowel causing bloating, wind and pain. This can also cause water to move into and out of the colon, causing diarrhoea, constipation or a combination of both. People with IBS are more susceptible to the problems that are associated with this. Milk

How to follow a low FODMAP diet
Under the supervision of a dietitian, high FODMAP foods are eliminated from the diet for six to eight weeks and replaced with suitable alternatives. After this, small amounts of FODMAP foods are gradually re-introduced to find a level of tolerance without the symptoms returning. It is not designed to be a ‘diet for life’ as many high FODMAP foods are important for stimulating the growth of beneficial bacteria in the gut.

It is important to remember not everyone will have a problem with every FODMAP. Some people might have symptoms triggered by one or two types of FODMAPs, whereas others may be sensitive to all five. The reasons for this are unknown, but foods should only be restricted if they contribute to symptoms. The diet is intended to be individualised according to the problematic FODMAP, so it is very important to seek guidance from a dietician.