Recently we have started hearing more about FODMAPs and FODMAP diets… Ask an Australian, and the term “FODMAP” is already well known. However, this term is just beginning to reach other parts of the world. The acronym FODMAP stands for fermentable oligosaccharide, disaccharide, monosaccharide and polyols. A mouthful so, lets stick to the acronym! Created by clinical researchers at Monash University (Melbourne, Australia), this unique diet was designed to treat irritable bowel syndrome (IBS). The success of FODMAP restriction and individualized FODMAP dietary guidance has proven to be a promising treatment to reduce GI symptoms in IBS patients; a condition estimated to effect up to 15% of the population.
Interestingly, symptoms of IBS are very similar in athletes who experience GI symptoms during or after exercise (1). Some symptoms common to both IBS and GI symptoms during exercise include bloating, diarrhea/loose stool, flatulence and abdominal pain. Emerging theory and evidence suggests that the use of low FODMAP diet or FODMAP restriction may be beneficial to reduce symptoms in athletes who struggle with persistent exercise-associated GI issues (2).
FODMAPs are a family of short chain carbohydrates that occur in a wide range of foods from onions to wheat-based breads. This family of poorly absorbed short-chain carbohydrates have been shown to increase osmotic load in the small intestine. This means that water will be drawn into the intestine and this can cause diarrhea. Upon transit to the colon FODMAPS are rapidly fermented (broken down) by colonic bacteria, creating gas. Mechanisms for FODMAPs potentially increasing symptoms in athletes are still being explored but many foods have been distinctly categorized as high or low FODMAP (At Monash University they developed a beautiful app that helps to find out which foods are high or low in FODMAPS, (Monash phone app). It is possible that FODMAPs ingested before or after strenuous endurance exercise could worsen exercise-related GI symptoms. This is still very new area of research and the athlete-specific mechanisms are not yet understood. Below are a list of high FODMAP foods that may be ingested frequently or in high quantities by athletes, particularly around or during competition.
It is still very early days to draw firm conclusions about the use of a low FODMAP approach to prevent exercise-associated GI problems. However, this diet may be promising tool for athletes struggling with GI distress. It is important to note that clinically healthy endurance athletes with exercise-associated GI problems do not instinctively require a low FODMAP diet and it can be very restrictive. If you are unnecessarily restricting your diet you may cause more problems than you are solving.
However, a simple change such as switching from a high FODMAP energy bar to a lower FODMAP alternative may be all that is required to reduce symptoms. High and low FODMAP foods, or the ones in between, can be challenging to navigate. If considering a low FODMAP diet it is advisable to work with an experienced practitioner and become properly educated. Continue reading here: Low FODMAP: A novel tool prevent GI problems?
Costa RJS, Snipe RMJ, Kitic CM, Gibson PR. Systematic review: exercise-induced gastrointestinal syndrome-implications for health and intestinal disease. Aliment Pharmacol Ther. 2017;46(3):246-265.
Lis DM, Stellingwerff T, Kitic CM, Fell JW, Ahuja KDK. Low FODMAP: A Preliminary Strategy to Reduce Gastrointestinal Distress in Athletes. Med Sci Sports Exerc. In press.