What is the low-FODMAP diet?

  1. Dr. Schär Institute
  2. What is the low-FODMAP diet?

FODMAPs are common short-chain, fermentable carbohydrates that are widespread throughout a number of food groups, including wheat. Research has shown that ingesting FODMAPs can provokegastrointestinal symptoms in susceptible individuals [1,2].

The abbreviation FODMAPs stands for fermentable oligosaccharides, disaccharides, monosaccharides and polyols. This group of short-chain, fermentable carbohydrates includes fructans, which are predominantly found in wheat. A diet low in FODMAPs has been found to be effective in the management of irritable bowel syndrome (IBS) [1,3,4]. The mechanisms by which these fermentable carbohydrates provoke gut symptoms are due to two underlying physiological processes. First, they are indigestible and subsequently fermented by the bacteria in the colon. This fermentation leads to gas production. The resulting gas can alter the gut environment and cause hypersensitivity in those who are susceptible to gut pain [1]. The second process is an osmotic effect. The fermentable carbohydrates increase water delivery to the colon leading to altered bowel habit [2].

Only introduce the diet under professional guidance

Despite the benefits, research suggests that this diet can have a detrimental effect on the gut bacteria [4]. The diet is also potentially low

in calcium, and therefore should only be used for 8 weeks. At the end of the 8 week trial all the removed foods are reintroduced individually in a stepwise manner. The food is added slowly and tolerance monitored. Food that are reintroduced and tolerated may then remain part of the new diet. Research indicates this diet to be very successful when counselling is provided by a trained dietitian [5,6]. Patients should be discouraged from attempting to follow a low FODMAP diet without appropriate support and information.

  • Which FODMAPs are found in which foods?

    This fact sheet shows which FODMAPs you can find in which foods. 

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A low FODMAP diet for IBS

There have been three randomized controlled trials published showing a clear benefit of using the Low FODMAP diet for IBS (1,3,4) and this data, along with three prospective uncontrolled trials (8-10) and two further retrospective trials (7,8), has led to fermentable carbohydrate restriction becoming an important treatment option for patients with IBS. Research indicates that patients using this diet report a marked improvement in symptoms, with up to 70% of patients reporting benefit (9). The Low FODMAP Diet is now noted on the NICE Guidance (10) and in the British Dietetic Association IBS Guidance (11).

References

  1. Ong DK MS, Barrett JS, Shepherd SJ, Irving PM, Biesiekierski JR, Smith S, Gibson PR, Muir JG,. Manipulation of dietary short chain carbohydrates alters the pattern of gas production and genesis of symptoms in irritable bowel syndrome. Journal of gastroenterology and hepatology. 2010;25(8):1366-73
  2. Murray K, Wilkinson-Smith V, Hoad C, Costigan C, Cox E, Lam C, et al. Differential effects of FODMAPs (fermentable oligo-, di-, mono-saccharides and polyols) on small and large intestinal contents in healthy subjects shown by MRI. Am J Gastroenterol. 2014;109(1):110-9.
  3. Halmos EP, Power VA, Shepherd SJ, Gibson PR, Muir JG. A diet low in FODMAPs reduces symptoms of irritable bowel syndrome. Gastroenterology. 2014;146(1):67-75 e5.
  4. Staudacher HM, Lomer MC, Anderson JL, Barrett JS, Muir JG, Irving PM, et al. Fermentable carbohydrate restriction reduces luminal bifidobacteria and gastrointestinal symptoms in patients with irritable bowel syndrome. The Journal of nutrition. 2012;142(8):1510-8.
  5. Staudacher HM, Whelan K, Irving PM, Lomer MC. Comparison of symptom response following advice for a diet low in fermentable carbohydrates (FODMAPs) versus standard dietary advice in patients with irritable bowel syndrome. J Hum Nutr Diet. 2011;24(5):487-95.
  6. Gibson PR, Barrett JS, Muir JG. Functional bowel symptoms and diet. Intern Med J. 2013;43(10):1067-74.
  7. Gearry R, 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. Journal of Crohns and Colitis. 2009;3(1):8-14
  8. Ostgaard H, Hausken T, Gundersend D, El-Salhy M. Diet and effects of diet management on quality of life and symptoms in patients with irritable bowel syndrome. Mol Med Rep. 2012;5:1382-90.
  9. Staudacher HM, Irving PM, Lomer MC, Whelan K. Mechanisms and efficacy of dietary FODMAP restriction in IBS. Nat Rev Gastroenterol Hepatol. 2014.
  10. Staudacher HM, Whelan K, Irving PM, Lomer MC. Comparison of symptom response following advice for a diet low in fermentable carbohydrates (FODMAPs) versus standard dietary advice in patients with irritable bowel syndrome. J Hum Nutr Diet. 2011;24(5):487-95.
  11. Gibson PR, Barrett JS, Muir JG. Functional bowel symptoms and diet. Intern Med J. 2013;43(10):1067-74.