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NHD CPD eArticle Volume 9.03 - 7th March 2019

THE LOW-FODMAP DIET FOR CROHN’S DISEASE Priya Tew Freelance Dietitian and Specialist in Eating Disorders Priya runs Dietitian UK, a freelance dietetic service that specialises in social media and media work, consultancy for food companies, eating disorder support, IBS and chronic fatigue. She works with NHS services, The Priory Hospital Group and private clinics, as well as providing Skype support to clients nationwide.

This article will look into current research in the area of the low-FODMAP diet and its effect on functional gut symptoms. Crohn’s disease is an autoimmune condition that can affect anywhere along the gastrointestinal tract, with ulceration and an unpredictable relapsing remitting course. Symptoms commonly include abdominal pain, bloody diarrhoea, fatigue, loss of appetite and weight loss. FODMAPs are short-chain carbohydrates that are poorly absorbed in the small intestine, then passed to the colon; the process of fermentation by the colonic microflora leads to an osmotic effect. This draws fluid into the lumen and causes an increase in gas production, resulting in abdominal pain, bloating, flatulence and diarrhoea in some individuals. There is strong evidence for the use of the lowFODMAP diet for IBS management and, now, it also appears to decrease functional gut symptoms in IBD. People with IBD are three times more likely to have IBS-style symptoms than the normal population.1 A small scale study on 52 patients with Crohn’s and 20 with ulcerative colitis found that one in two patients responded well to a low-FODMAP diet (improvement of at least 5/10 in symptoms) for abdominal pain, bloating, wind and diarrhoea.2 A UK study on 180 patients with IBS or IBD given low-FODMAP advice via a dietetic/nutrition-led clinic, found normal stools improved by 66% in the

IBD group. A higher adherence was associated with a longer duration of symptom improvement. Foods most often not reintroduced were wheat and onion (fructans) and dairy.3 It was concluded that the low-FODMAP diet seems to decrease functional gut symptoms in IBD. Another study on 88 people looked at symptoms and stool, finding a significant improvement on the lowFODMAP diet in symptoms and stool consistency.4 IS ONE FODMAP OF MORE CONCERN THAN ANOTHER?

A series of three-day fermentable carbohydrate challenges of fructans, galacto-oligosaccharides (GOS) and sorbitol were compared to glucose placebo on 32 patients with quiescent IBD. 12 of the patients had Crohn’s disease. Although a small scale study with limitations, it was found that fructans at high doses exacerbated symptoms.5 Another study6 shows that patients with active Crohn’s disease consume lower quantities of fructans and oligofructose than their inactive counterparts and healthy controls. This case control study used a food frequency questionnaire comparing 98 people with active Crohn’s disease, 99 with inactive Crohn’s disease and 106 healthy controls. A lower fructan intake was found in those with active

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NHD CPD eArticle Volume 9.03 - 7th March 2019 Table 1: Prebiotic foods FODMAP foods that are prebiotics

Low-FODMAP foods that are prebiotics – (portion sizes where indicated limit the foods to low FODMAP)

Wheat/rye breads, couscous, wheat pasta, barley and gnocchi

Chicory leaves (<1 cup), fennel bulb ( ½ cup), green section of leeks and spring onions, beetroot (2 slices or 20g), sweetcorn ( ½ cob), canned lentils ( ½ cup), red cabbage (1 cup)

Jerusalem artichokes, garlic, onion, leeks, asparagus, beetroot, peas, snow peas, and sweetcorn

Banana, rhubarb, kiwifruit, dried cranberries (1 tbsp), pomegranate (½ small or ¼ cup seeds).

Nectarines, peaches, watermelon, persimmons, grapefruit, pomegranate, dried fruit


Cashews and pistachios Foods containing inulin

Crohn’s disease compared to the other two groups. More research is needed to look into the impact of lower intakes of prebiotic fructans on gut microbiota.

on the low-FODMAP diet in all subjects and it was suggested that this diet was a valid option in non-active IBD to improve quality of life and social occasions.9



Crohn’s disease can be intermittent with periods of remission and activity. Even in remission there can be some functional gut symptoms that persist. These symptoms can be similar to IBS symptoms and up to 40% of those with Crohn’s can suffer.7 A very small study on eight people in Australia suggested that the low-FODMAP diet may be more useful in periods when the disease is inactive. Patients were fed either a low-FODMAP diet or a typical Australian diet for three weeks, followed by a three-week washout period before the diets were switched over. The native diet had a prebiotic effect, likely due to the levels of oligosaccharides and polyols. Symptoms of abdominal pain, bloating and flatulence almost doubled on the low-FODMAP diet. This was suggested to be due to the patients being in active Crohn’s.8 Comparing this to a Danish non-blinded RCT, where the 89 people studied had IBS in remission, or IBD with functional gut symptoms, a low-FODMAP diet decreased the functional gut symptoms and increased the quality of life in the IBD group.7 This has been backed up by a study on 127 people, 56 with IBS, 30 with IBD and 41 with coeliac disease. Abdominal symptoms improved after one and three months

Some of the evidence on this topic is unclear and weak, but it can still highlight limitations of using the low-FODMAP diet with this population group. Caution is needed when using a restrictive diet with people who may already be nutritionally compromised. They could be malabsorbing, or consuming foods that they already know need to be avoided.10 The lowFODMAP diet can be a good treatment option if careful attention is paid to the nutritional adequacy of the patient’s diet.11 If it is needed for a long-term approach, then dietary supplements will be required to avoid deficiencies.12 In active states, vitamin B12, folate, B6 and vitamin D can be low.13 MICROBIOME

The low-FODMAP diet restricts the intake of many foods that are high in probiotics, therefore, this is not a diet to be on long term as it can impact on the microbiome. These prebiotic food, however, are good for gut health, helping with the growth of beneficial bacteria (see Table 1). This is not limited to Crohn’s, as decreased levels of Bifidobacteria and faecalibacterium prausnitzii have been found in IBS patients on the lowFOMDAP diet, so this is likely to occur in anyone on this diet.7 Encouraging people to consume

Copyright © 2019 NH Publishing Ltd - All rights reserved. Available for printing and sharing for the use of CPD activities for personal use. Not for reproduction for publishing purposes without written permission from NH Publishing Ltd.

NHD CPD eArticle Volume 9.03 - 7th March 2019 more prebiotics that are low in FODMAPs may be helpful, as well as keeping the elimination phase to weeks and not months. CONCLUSION

The low-FODMAP diet does appear to have a place in the treatment of Crohn’s disease. It may be more helpful for inactive stages of the disease, but there are limitations to consider. The lowFODMAP diet can impact on the microbiome in the short term, plus there is concern about the nutritional adequacy of this population group, so it can be concluded that the low-FODMAP

diet should be used in the short term only. This is exactly how the diet was designed to be used, but many people stay on the restrictive, exclusive phase of the diet. This can be due to fear of their symptoms reappearing, or a lack of support and education from their nutrition team. Encouraging and empowering people to the reintroduction stage is vital for their longterm health. If, for some reason, a patient does need to follow the exclusion stage long term, then supplements are likely to be needed to help the microbiome and to correct nutritional deficiencies.

References 1 A low-FODMAP diet in inflammatory bowel disease (IBD) - an update by Dr Emma Halmos. www.monashfodmap.com/blog/ low-fodmap-diet-inflammatory-bowel-disease-ibd-update/ 2 Irving PM, Barrett JS, Nathan DM, Shepherd SJ, Gibson PR. Reduction of dietary poorly absorbed short-chain carbohydrates (FODMAPs) improves abdominal symptoms in patients with inflammatory bowel disease-a pilot study. J Crohn’s Colitis. 2009 Feb; 3(1): 8-14 3 Maagaard L1, Ankersen DV1, Végh Z1, Burisch J1, Jensen L1, Pedersen N1, Munkholm P1. Follow-up of patients with functional bowel symptoms treated with a low FODMAP diet. World J Gastroenterol. 2016 Apr 21; 22(15): 4009-19 4 Prince AC, Myers CE, Joyce T, Irving P, Lomer M, Whelan K. Fermentable Carbohydrate Restriction (Low FODMAP Diet) in Clinical Practice Improves Functional Gastrointestinal Symptoms in Patients with Inflammatory Bowel Disease. Inflamm Bowel Dis. 2016 May; 22(5): 1129-36 5 Cox SR, Prince AC, Myers CE, Irving PM, Lindsay JO, Lomer MC, Whelan K. Fermentable Carbohydrates [FODMAPs] Exacerbate Functional Gastrointestinal Symptoms in Patients With Inflammatory Bowel Disease: A Randomised, Double-blind, Placebo-controlled, Cross-over, Re-challenge Trial. J Crohn’s Colitis. 2017 Dec 4; 11(12): 1420-1429 6 Anderson JL, Hedin CR, Benjamin JL, Koutsoumpas A, Ng SC, Hart AL, Forbes A, Stagg AJ, Lindsay JO, Whelan K. Dietary intake of inulin-type fructans in active and inactive Crohn’s disease and healthy controls: a case-control study. J Crohn’s Colitis. 2015 Nov; 9(11) 7 Pedersen N, Ankersen DV, Felding M, Wachmann H, Végh Z, Molzen L, Burisch J, Andersen JR, Munkholm P. Low-FODMAP diet reduces irritable bowel symptoms in patients with inflammatory bowel disease. World J Gastroenterol. 2017 May 14; 23(18): 3356-3366 8 Emma P Halmos, Claus T Christophersen, Anthony R Bird, Susan J Shepherd, Jane G Muir and Peter R Gibson. Altered FODMAP Intake in Patients with Crohn’s Disease: A Randomised, Controlled Cross-Over Trial of Well-Defined Diets. Clin Transl Gastroenterol. 2016 Apr; 7(4): e164 9 Testa A, Imperatore N, Rispo A, Rea M, Tortora R, Nardone OM, Lucci L, Accarino G, Caporaso N, Castiglione F. Beyond Irritable Bowel Syndrome: The Efficacy of the low-FODMAP diet for Improving Symptoms in Inflammatory Bowel Diseases and Celiac Disease. Dig Dis. 2018; 36(4): 271-280 10 Gibson PR. Use of the low-FODMAP diet in inflammatory bowel disease. J Gastroenterol Hepatol. 2017 Mar; 32 Suppl 1: 40-42 11 Colombel JF, Shin A, Gibson PR. Functional Gastrointestinal Symptoms in Patients With Inflammatory Bowel Disease. Clin Gastroenterol Hepatol. 2018 Aug 9. S1542-3565(18)30810-3 12 Barbalho SM, Goulart RA, Aranão ALC, de Oliveira PGC. Inflammatory Bowel Diseases and Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols: An Overview. J Med Food. 2018 Jul 21(7): 633-640 13 BDA: Management of Crohn’s disease - recent developments. www.bda.uk.com/dt/articles/crohnsdisease

Coming in the April issue

• Special needs infant formula


• Adult food allergies

• Goat milk

• ONS on the ward • Liver disease

• Dysphagia meal replacements • Being a prescribing dietitian


Copyright © 2019 NH Publishing Ltd - All rights reserved. Available for printing and sharing for the use of CPD activities for personal use. Not for reproduction for publishing purposes without written permission from NH Publishing Ltd.

NHD CPD eArticle Volume 9.03 - 7th March 2019

Questions relating to: The low-FODMAP diet for Crohn’s disease Type your answers below, download and save or print for your records, or print and complete by hand. Q.1

What are FODMAPs and what effects can they have on the human gut?



Explain how a low-FODMAP diet can help with symptoms of IBS.



What evidence is there to show that active Crohn’s disease sufferers consume lower quantities of fructans?



What are the limitations of the low-FODMAP diet in the nutritional management of Crohn’s?



Why is the low-FODMAP diet not suitable for use long term?


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NHD CPD eArticle 9.03  

The low-FODMAP diet afor Crohn's disease by Priya Tew

NHD CPD eArticle 9.03  

The low-FODMAP diet afor Crohn's disease by Priya Tew