Manipulation of dietary short chain carbohydrates alters the pattern of gas production and genesis of symptoms in irritable bowel syndrome.

BACKGROUND AND AIM: Reduction of short-chain poorly absorbed carbohydrates (FODMAPs) in the diet reduces symptoms of irritable bowel syndrome (IBS). In the present study, we aimed to compare the patterns of breath hydrogen and methane and symptoms produced in response to diets that differed only in FODMAP content. METHODS: Fifteen healthy subjects and 15 with IBS (Rome III criteria) undertook a single-blind, crossover intervention trial involving consuming provided diets that were either low (9 g/day) or high (50 g/day) in FODMAPs for 2 days. Food and gastrointestinal symptom diaries were kept and breath samples collected hourly over 14 h on day 2 of each diet. RESULTS: Higher levels of breath hydrogen were produced over the entire day with the high FODMAP diet for healthy volunteers (181 +/- 77 ppm.14 h vs 43 +/- 18; mean +/- SD P < 0.0001) and patients with IBS (242 +/- 79 vs 62 +/- 23; P < 0.0001), who had higher levels during each dietary period than the controls (P < 0.05). Breath methane, produced by 10 subjects within each group, was reduced with the high FODMAP intake in healthy subjects (47 +/- 29 vs 109 +/- 77; P = 0.043), but was not different in patients with IBS (126 +/- 153 vs 86 +/- 72). Gastrointestinal symptoms and lethargy were significantly induced by the high FODMAP diet in patients with IBS, while only increased flatus production was reported by healthy volunteers. CONCLUSIONS: Dietary FODMAPs induce prolonged hydrogen production in the intestine that is greater in IBS, influence the amount of methane produced, and induce gastrointestinal and systemic symptoms experienced by patients with IBS. The results offer mechanisms underlying the efficacy of the low FODMAP diet in IBS.

Irritable bowel syndrome: contemporary nutrition management strategies.

Irritable bowel syndrome is a complex disorder whose pathophysiology involves alterations in the enteric microbiota, visceral hypersensitivity, gut immune/barrier function, hypothalamic-pituitary-adrenal axis regulation, neurotransmitters, stress response, psychological factors, and more. The importance of diet in the management of irritable bowel syndrome has taken center stage in recent times as the literature validates the relationship of certain foods with the provocation of symptoms. Likewise, a number of elimination dietary programs have been successful in alleviating irritable bowel syndrome symptoms. Knowledge of the dietary management strategies for irritable bowel syndrome will help guide nutritionists and healthcare practitioners to deliver optimal outcomes. This tutorial reviews the nutrition management strategies for irritable bowel syndrome.

Reduction of dietary poorly absorbed short-chain carbohydrates (FODMAPs) improves abdominal symptoms in patients with inflammatory bowel disease-a pilot study.

OBJECTIVE: Functional gut symptoms are common in patients with inflammatory bowel disease (IBD). Since poorly absorbed, short-chain carbohydrates (FODMAPs) appear to play an important role in the induction of functional gut symptoms, we aimed to determine the effect of their dietary restriction on abdominal symptoms in patients with stable IBD and to examine factors associated with success of and adherence to the diet. MATERIAL AND METHOD: 52 consecutive patients with Crohn's disease and 20 with ulcerative colitis who received dietary advice at least 3 months prior at a gastrointestinal dietetic service in Victoria, Australia, underwent a retrospective telephone questionnaire. Information gathered included patient demographics, recall of dietary advice, dietary adherence, and change in gastrointestinal symptoms. RESULTS: Up to 70% of patients were adherent to the diet. Approximately one in two patients responded (defined as improvement of at least 5 out of 10 in overall symptoms). Overall abdominal symptoms, abdominal pain, bloating, wind and diarrhoea improved in patients with Crohn's disease and ulcerative colitis (p<0.02 for all), but constipation did not. For Crohn's disease, efficacy was associated with dietary adherence (p= 0.033) and inefficacy with non-adherence (p=0.013). Sustained response was associated with post-secondary education and working 35 h per week or less (p<0.03). CONCLUSIONS: These data suggest that reduction of FODMAP intake offers an efficacious strategy for patients with IBD who have concurrent functional gut symptoms. A controlled dietary intervention trial is indicated.