Secondary Logo

Share this article on:

Limiting FODMAP consumption for patients with IBS

Heavey, Elizabeth, PhD, RN, CNM; Daniel, Eileen, RD, EdD

doi: 10.1097/01.NURSE.0000545020.29285.c1

Abstract: Irritable bowel syndrome (IBS) is a chronic disorder affected by stress and dietary habits. This article explores the role of diets low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols in reducing IBS symptoms.

Teach patients with irritable bowel syndrome (IBS) how a diet low in specific fermentable substances can help them reduce symptoms.

Elizabeth Heavey is the graduate program director and professor of nursing at the State University of New York, Brockport, and a member of the Nursing2018 editorial board. Eileen Daniel is a professor of public health education and vice provost for academic affairs at the State University of New York, Brockport.

The authors have disclosed no financial relationships related to this article.



IRRITABLE BOWEL SYNDROME (IBS) is a chronic functional gastrointestinal (GI) disorder, meaning that patients are symptomatic without any underlying damage to the GI system. Diagnosis is made after excluding other pathologic processes with similar presentations that can harm the GI tract, including inflammatory bowel disease, celiac disease, and intestinal cancers.

Patients with IBS experience abdominal pain with diarrhea and/or constipation, gas, bloating, and fecal urgency. One treatment option involves identifying foods that trigger IBS signs and symptoms and modifying the diet to avoid them. A diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP) has been shown to help patients manage IBS symptoms.1-5 This article discusses why a low-FODMAP diet may help patients with IBS and describes how to implement one.

Back to Top | Article Outline

Physical and psychological effects

An estimated 10% to 20% of adults in the US have IBS.6 Besides pain, bloating, unintentional weight loss, and nutritional deficiencies, up to 60% of patients experience a psychological impact, potentially resulting in depression and anxiety.1,7 In the US, healthcare costs associated with IBS are estimated to be over $1.6 billion a year.2

Although many patients with IBS are managed in primary care settings, IBS is the underlying reason behind approximately 50% of referrals made to GI specialists.1 It is frequently diagnosed in adults under age 50 and occurs twice as often in women as it does in men.1,6

Both stress and specific foods have been reported to trigger GI symptoms in 70% to 89% of patients with IBS.2 Why certain foods are associated with signs and symptoms of IBS remains unclear, but consumption of these foods can result in altered GI motility, abnormal colonic fermentation, and sugar malabsorption—all of which lead to gas production and abdominal distension.8

A dietary modification treatment approach helps patients identify and avoid foods that trigger IBS symptoms. Despite a limited number of randomized clinical trials, a low-FODMAP diet has been shown to decrease symptoms in 50% to 80% of patients with IBS.1-5

Back to Top | Article Outline

How a high-FODMAP diet affects symptoms

As carbohydrates and sugar alcohols are consumed by normal intestinal bacteria, rapid fermentation occurs, producing carbon dioxide and colonic distension.7 High-FODMAP foods are poorly absorbed and osmotically active, pulling water into the intestinal lumen where they undergo rapid fermentation. This causes abdominal bloating and pain and may produce an urgent need to defecate as watery stool rapidly moves through the intestines.6,9 Consumption of these substances also appears to impact the composition and metabolic output of GI microorganisms (gut flora), impacting both hydrogen and histamine levels.2 Though still being studied, these changes appear to correlate with symptom exacerbation in some IBS patients.2 Visceral hypersensitivity and abnormal motility are characteristic symptoms of IBS.10

High-FODMAP foods include short-chain carbohydrates (monosaccharides, disaccharides, and oligosaccharides) and sugar alcohols (polyols).7 These highly fermentable carbohydrates can be found in lactose-containing dairy products, fruit, wheat, and some artificial sweeteners, as well as in gas-producing foods such as beans, cabbage, and broccoli.6 Decreasing the consumption of foods that enable these processes may decrease the associated symptoms.7,11

Back to Top | Article Outline

Implementation and assessment

Typically, patients starting a low-FODMAP diet are asked to keep a symptom diary and to eliminate all high-FODMAP foods for 6 to 8 weeks, although some dietitians have reported success with shorter elimination periods (2 to 4 weeks).7 After the elimination stage, the symptom diary is reviewed and an assessment is made regarding the effects of the diet. If symptoms are not relieved during this elimination phase, the next phase should not be implemented because it is unlikely to produce improvement.7

Patients who experience symptom relief during the first stage move to the second stage of the diet, which involves selecting specific high-FODMAP foods or food groups and reintroducing them in small amounts while monitoring symptoms. If reintroducing a food produces symptoms, patients should avoid it in the future and wait until they are symptom-free (typically 3 to 4 days) before adding another high-FODMAP food back into their diet.7 If it triggers no symptoms, a larger portion is tested for manifestations associated with the increased amount.7 Some patients with IBS will have greater sensitivity to particular groups of high-FODMAP foods, while others may tolerate those without issue. (For examples of foods patients typically include in or eliminate from low-FODMAP diets, see Common dietary modifications for patients on a low-FODMAP diet.)

Back to Top | Article Outline

Long-term outcomes are uncertain

Only a limited number of studies have examined the long-term effects of a low-FODMAP diet, but a clinical benefit is suggested for 57% to 74% of patients 14 to 16 months after initiation.2 Several studies have reported a significant effect on the quantity and composition of gut flora with an unknown impact, positive or negative, on long-term health outcomes.2 The mediating roles of pre- and probiotics are currently being explored.12 More research is needed to determine if the restriction of high-FODMAP foods is significantly better than restricting specific sugars such as lactose or fructose.2

Besides a lack of research to guide food choices, the use of low-FODMAP diets is complicated by the fact that many packaged foods do not quantify their FODMAP contents. In addition, safe levels for FODMAP ingredients are not clearly defined or regulated yet and are often determined by individual patients on a trial-and-error basis, which can involve significant symptom exacerbations.8

Back to Top | Article Outline

Interdisciplinary team interventions

Because many foods contain high-FODMAP ingredients, patients attempting these diets should work with an experienced dietitian who can provide guidance. Patient education about low-FODMAP alternatives is essential to help them avoid nutritional deficiencies and promote adherence to the plan, especially during the elimination phase of the diet.7 Particular attention should be paid to identifying alternative sources of calcium and iron.2

Additionally, group dietary counseling has demonstrated the same level of effectiveness in beginning a low-FODMAP diet as one-on-one dietary counseling at about 50% of the cost.13 Nurses provide education, support, and encouragement to patients implementing a low-FODMAP diet. Those working in GI-focused practices may choose to pursue specialized training in low-FODMAP dietary counseling.10 (For more information, see Additional resources.)

Back to Top | Article Outline

Managing quality-of-life issues

Significant dietary restrictions can impact patients' plans for travel, social engagements, and workplace interactions. Managing socially unacceptable symptoms and dietary restrictions can result in feelings of isolation, undermining interpersonal relationships.16

Nurses can help by regularly assessing patients' stress levels and support networks. Promoting relaxation techniques may help patients cope, and referrals to support groups available both online or locally may help them combat some of the frustrations associated with managing IBS.16

Back to Top | Article Outline

Common dietary modifications for patients on a low-FODMAP diet3,10,14,15

Foods to avoid:

  • dairy products with lactose: cow's milk and foods made with cow's milk; ice cream; yogurt; cottage, ricotta, and mozzarella cheeses
  • “free fructose” (fructose in excess of glucose) and polyols: apples, pears, cherries, honey, dates, mushrooms, “stone” fruits such as peaches, and products with high-fructose corn syrup
  • fructans and galactans: onions, garlic, wheat, rye, beans, and watermelons
  • gas-producing foods: beans, broccoli, peas, cabbage, and bran
  • artificial sweeteners: sorbitol, mannitol, xylitol, and maltitol.

Foods to include:

  • dairy: lactose-free milk products, rice and almond milk, lactose-free yogurt, and hard cheeses such as swiss and cheddar
  • fruits: bananas, blueberries, cantaloupe, grapefruit, honeydew, kiwi, lemon, lime, oranges, and strawberries
  • vegetables: bamboo shoots, bean sprouts, bok choy, carrots, chives, cucumbers, eggplant, ginger, lettuce, olives, parsnips, potatoes, spring onions, and turnips
  • proteins: beef, pork, chicken, fish, eggs, and tofu
  • nuts/seeds (limit to 10-15 each): almonds, macadamia nuts, peanuts, pine nuts, and walnuts
  • grains: oat, oat bran, rice bran, gluten-free pasta made with rice flour, corn flour, and/or quinoa.
Back to Top | Article Outline

Additional resources

Back to Top | Article Outline


1. Weaver KR, Melkus GD, Henderson WA. Irritable bowel syndrome. Am J Nurs. 2017;117(6):48–55.
2. Staudacher HM, Whelan K. The low FODMAP diet: recent advances in understanding its mechanisms and efficacy in IBS. Gut. 2017;66(8):1517–1527.
3. Altobelli E, Del Negro V, Angeletti PM, Latella G. Low-FODMAP diet improves irritable bowel syndrome symptoms: a meta-analysis. Nutrients. 2017;9(9).
4. Zhan YL, Zhan YA, Dai SX. Is a low FODMAP diet beneficial for patients with inflammatory bowel disease? A meta-analysis and systematic review. Clin Nutr. 2018;37(1):123–129.
5. Schumann D, Klose P, Lauche R, Dobos G, Langhorst J, Cramer H. Low fermentable, oligo-, di-, mono-saccharides and polyol diet in the treatment of irritable bowel syndrome: a systematic review and meta-analysis. Nutrition. 2018;45:24–31.
6. Varjú P, Farkas N, Hegyi P, et al Low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diet improves symptoms in adults suffering from irritable bowel syndrome (IBS) compared to standard IBS diet: a meta-analysis of clinical studies. PLoS One. 2017;12(8):e0182942.
7. Riggs S. The low-FODMAP diet: an approach for controlling irritable bowel syndrome. Top Clin Nutr. 2014;29(4):304–312.
8. Magge S, Lembo A. Low-FODMAP diet for treatment of irritable bowel syndrome. Gastroenterol Hepatol (N Y). 2012;8(11):739–745.
9. Wald A, Talley NJ, Grover S. Treatment of irritable bowel syndrome in adults. UpToDate. 2018.
10. Medlin S. The low FODMAP diet: new hope for irritable bowel syndrome sufferers. Gastrointest Nurs. 2012;10:9,37–41.
11. Ireton-Jones C. The low FODMAP diet: fundamental therapy in the management of irritable bowel syndrome. Curr Opin Clin Nutr Metab Care. 2017;20(5):414–419.
12. Staudacher HM, Lomer MCE, Farquharson FM, et al A diet low in FODMAPs reduces symptoms in patients with irritable bowel syndrome and a probiotic restores bifidobacterium species: a randomized controlled trial. Gastroenterology. 2017;153(4):936–947.
13. O'Keeffe M, Lomer MC. Who should deliver the low FODMAP diet and what educational methods are optimal: a review. J Gastroenterol Hepatol. 2017;32(suppl 1):23–26.
14. Wald A, Talley NJ, Grover S. Treatment of irritable bowel syndrome in adults. UpToDate. 2018.
15. Hammer HF, Högenauer C, Friedman LS, Grover S. Lactose intolerance: clinical manifestations, diagnosis, and management. UpToDate. 2018.
16. Mason I. Supporting community patients with irritable bowel syndrome (IBS). J Community Nurs. 2014;28(1):28–33.

fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP); gastrointestinal; high-FODMAP; irritable bowel syndrome; low-FODMAP

Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved.