Symptoms of abdominal pain, gas, bloating, flatulence, burping, constipation and/or diarrhea are commonly present in various gastrointestinal disorders but are hard to treat and minimize symptoms. Often these symptoms are called Irritable Bowel Syndrome (IBS). If you have IBS or a constellation of chronic GI complaints for which no other disease or condition has been identified, consider a diet low in fermentable oligo-, di-, and monosaccharides and polyls (FODMAPs). This is a diet that limits, but does not eliminate, foods that contain:
These compounds in food are poorly absorbed, highly osmotic and rapidly fermented by GI bacteria, leading to increased water and gas in the GI tract, which then leads to GI tract distention that causes changes in GI motility, bloating, discomfort and flatulence.
To assess your tolerance for these compounds, eliminate foods high in FODMAPs for 6-8 weeks and then gradually reintroduce foods to identify bothersome foods. Reintroduce one food every four days with a 2-week break between bothersome foods. The goal is to identify the threshold at which you are able to consume FODMAP containing foods without causing bothersome GI symptoms.
Lactose is the carbohydrate found in cow’s, sheep’s, and goat’s milk. Lactose intolerance is caused by partial or complete lack of the enzyme lactase which digests lactose. When lactose is not completely digested, it contributes to abdominal bloating, pain, gas, and diarrhea, often occurring 30 minutes to two hours following the consumption of milk and milk products.
Limit foods high in lactose such as yogurt, ice cream, milk, and ricotta and cottage cheeses. See FODMAPs in Food table.
Fructose is a carbohydrate found in fruit, honey, high-fructose corn syrup (HFCS), and agave syrup, but not all fructose containing foods need to be limited on a low FODMAPs diet. Fructose malabsorption is similar to lactose intolerance, in that fructose is not completely digested in the GI tract due to the lack of an enzyme, but unlike lactose intolerance the absorption of fructose is dependent on another carbohydrate, glucose. Therefore, fructose-containing foods with a 1:1 ratio of fructose to glucose are generally well tolerated on the FODMAPs diet and conversely, foods with excess fructose compared with glucose, such as apples, pears, and mangos, will likely trigger abdominal symptoms.
Limit foods with excess free fructose, see FODMAPs in Food table.
Fructans are carbohydrates that are completely malabsorbed because the intestine lacks an enzyme to break their fructose- fructose bond. For this reason, fructans can contribute to bloating, gas, and pain. Wheat accounts for the majority of people’s fructan intake.
Limit wheat, onions and garlic along with other vegetables high in fructans, see FODMAPs in Food table.
Galactans are carbohydrates are malabsorbed for the same reason as fructans; the intestine does not have the enzyme needed to break down galactans. Consequently, galactans can contribute to gas and GI distress.
Limit beans and lentils. See FODMAPs in Food table.
Polyols are also known as sugar alcohols. They are found naturally in some fruits and vegetables and added as sweeteners to sugar-free gums, mints, cough drops, and medications. Sugar alcohols have varying effects on the bowel.
Limit sugar alcohols, sorbitol, xylitol, mannitol andmaltitol. See FODMAPs in Food table.
FODMAPs Elimination and Challenge
Use the table below to guide your choices. Eliminate foods high in FODMAPs for 6-8 weeks. You should notice an improvement in your GI complaints within one week of following a low FODMAP diet. Follow a low FODMAP diet for a full 6-8 weeks before assessing its effectiveness and reintroducing foods high in FODMAPs. At that time you will work with you Nutrition Counselor to reintroduce one test food every four days; if you react to a food, do not test another food for two weeks.
Foods that are high in FODMAPs may aggravate your GI complaints but they are not causing an allergic reaction or an autoimmune reaction in your body. The foods high in FODMAPs that elicit GI symptoms are causing functional discomfort in your gut that result in gas, bloating, distention etc.
These are the test foods for each category:
You will work with your Nutrition Counselor to determine the order of challenge and which foods to use.
Menu ideas adapted from Today’s Dietitian, March 2012
Online Resources for More Information
Gibson PR, Narrett, JS. Clinimal ramifications of malabsorption of fructose and other short-chain carbohydrates. Practical Gastroenterology, August 2007
Gibson PR, Sheperd SJ. Evidence-based dietary management of functional gastrointestinal symptoms: The FODMAP approach. J of Gastroenterology and Hepatology 25(2010) 252- 258
Scarlata, K. Sucessful Low FODMAP living. Today’s Dietitian, March 2012
Scarlata, K. The FODMAPs Approach — Minimize Consumption of Fermentable Carbs to Manage Functional Gut Disorder Symptoms. Today’s Dietitian, August 2010