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
Oats
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
ACTIVE VS INACTIVE CROHN’S
NUTRITIONAL ADEQUACY OF THE FODMAP DIET
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.