Gastroenterology 2014 Jan 01;146(1)67-75.e5, EP Halmos, VA Power, SJ Shepherd, PR Gibson, JG Muir
Research · January 16, 2014
TAKE-HOME MESSAGE
- IBS patients had fewer symptoms when on a diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs).
- The authors feel that this evidence supports the use of FODMAPs as first-line therapy for IBS.
Commentary By: David Rakel MD, FAAFP
What is FODMaP?
FODMaP is a dietary approach that a growing amount of research has shown reduces IBS symptoms. The diet is low in sugars that are difficult to absorb, leading to fermentation and gas, and osmotic as well, pulling fluid into the intestine, worsening diarrhea. This may explain that, although FODMaP improved symptoms by 50% for both diarrhea- and constipation-dominant IBS, it only reduced stool frequency for IBS-D. This well-done, crossover study supports using FODMaP nutritional recommendations as a first-line treatment for IBS.
The FODMaP Sugars
F = fermentable sugars: They may cause gas when in contact with gut microbiome.
O = oligosaccharides. These are fructans, which include wheat, rye, onion, garlic, beans, and some vegetables. This is unfortunate as many of these are really good for you. Wheat is omitted for its sugar, not for its protein (gluten). But a cross-over benefit may occur in those with gluten intolerance.
D = disaccharides: Lactose in milk and dairy products
M = monosaccharides: Fructose in high-fructose corn syrup, honey, and some fruits
a = and
P = polyol sweeteners: Any sugar ending in “ol,” such as xylitol, sorbitol, etc. Be careful of sugarless chewing gums and any food with artificial sweeteners.
Individuals on the FODMaP diet run the risk of significantly reducing their intake of fruits and vegetables, which could have negative long-term health consequences. I generally have my patients start with a modified FODMaP diet, in which they significantly reduce their FODMaP sugar load by avoiding dairy, wheat (breads and crackers), rye, high-fructose corn syrup, honey, and polyol sugars. If this doesn’t work, they can then do the full FODMaP diet that is described nicely in this patient handout.
ABSTRACT
BACKGROUND & AIMS
A diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) often is used to manage functional gastrointestinal symptoms in patients with irritable bowel syndrome (IBS), yet there is limited evidence of its efficacy, compared with a normal Western diet. We investigated the effects of a diet low in FODMAPs compared with an Australian diet, in a randomized, controlled, single-blind, cross-over trial of patients with IBS.
METHODS
In a study of 30 patients with IBS and 8 healthy individuals (controls, matched for demographics and diet), we collected dietary data from subjects for 1 habitual week. Participants then randomly were assigned to groups that received 21 days of either a diet low in FODMAPs or a typical Australian diet, followed by a washout period of at least 21 days, before crossing over to the alternate diet. Daily symptoms were rated using a 0- to 100-mm visual analogue scale. Almost all food was provided during the interventional diet periods, with a goal of less than 0.5 g intake of FODMAPs per meal for the low-FODMAP diet. All stools were collected from days 17-21 and assessed for frequency, weight, water content, and King’s Stool Chart rating.
RESULTS
Subjects with IBS had lower overall gastrointestinal symptom scores (22.8; 95% confidence interval, 16.7-28.8 mm) while on a diet low in FODMAPs, compared with the Australian diet (44.9; 95% confidence interval, 36.6-53.1 mm; P < .001) and the subjects’ habitual diet. Bloating, pain, and passage of wind also were reduced while IBS patients were on the low-FODMAP diet. Symptoms were minimal and unaltered by either diet among controls. Patients of all IBS subtypes had greater satisfaction with stool consistency while on the low-FODMAP diet, but diarrhea-predominant IBS was the only subtype with altered fecal frequency and King’s Stool Chart scores.
CONCLUSIONS
In a controlled, cross-over study of patients with IBS, a diet low in FODMAPs effectively reduced functional gastrointestinal symptoms. This high-quality evidence supports its use as a first-line therapy.