A Low FODMAP Diet

Foods have been known as the main trigger of digestive disorders. Proposing the diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) for reduction of gastrointestinal symptoms in irritable bowel syndrome (IBS), and inflammatory bowel disease (IBD) opened a new horizon in management of IBS. The hypothesis of psychologic problems in all IBS patients became weak after observation of symptom reductions followed by low FODMAP diet. Currently, low FODMAP diet is the first step of IBS management. Most of the patients would be symptom free after 2 weeks’ adherence to low FODMAP diet, unless they suffer from a major psychological problem. After 6-8 weeks, patients can follow a diet with less limitation, thus, this diet does not last for the long-life. FODMAP containing foods, then, can be challenged after the limitation period.FODMAPs are found in a wide range of foods in various amounts. Some foods contain several types of FODMAPS, while some others contain only one. The main dietary sources of FODMAPS are as follow: wheat, rye, legumes, garlic, onion, and most of fruits and vegetables contain fermentable oligosaccharides, milk, and soft cheese contain fermentable disaccharides, most of the fruits, honey, and artificial sweeteners contain fermentable monosaccharides and polyols.The mechanism of action for therapeutic effects of low FODMAP diet in amelioration of IBS symptoms is mainly explained by its effects on gut microbiota. FODMAP foods can be fermented by the intestinal bacteria producing gas, which leads to symptoms such as bloating and abdominal pain. Thus, adherence to low FODMAP diet reduces production of gas and consequently abdominal pain.Future studies should focus on new methods of patient education, and predictors of patient’s response. Moreover, the effects of this diet in other disorders, specially, other digestive disorders remained to be elucidated.