Increasing symptoms in irritable bowel symptoms with ingestion of galacto-oligosaccharides are mitigated by α-galactosidase treatment

C. J. Tuck, K. M. Taylor, P. R. Gibson, J. S. Barrett, J. G. Muir

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38 Citations (Scopus)


Objectives: Galacto-oligosaccharides (GOS) are dietary FODMAPs (fermentable carbohydrates) associated with triggering gastrointestinal symptoms in patients with irritable bowel syndrome (IBS). This randomized, double-blind, placebo-controlled, cross-over trial aimed to assess whether oral α-galactosidase co-ingestion with foods high in GOS and low in other FODMAPs would reduce symptoms. Methods: Patients meeting the Rome III criteria for IBS who were hydrogen-producers on breath testing were recruited. Participants were treated with full-dose (300 GALU (galactosidic units) α-galactosidase) and half-dose enzyme (150 GALU α-galactosidase), and placebo (glucose) in a random order with ≤14 days washout between arms. Following a 3-day low FODMAP run-in period, participants consumed provided diets high in GOS for a further 3-days. Gastrointestinal symptoms were measured daily using a 100 mm visual-analogue-scale, and breath samples taken hourly on the second last day with hydrogen content analysed as area-under-the-curve. Results: Thirty-one patients with IBS (20 IBS-D, 4 IBS-C, 7 IBS-M) completed the study. The addition of high GOS foods resulted in a significant increase in overall symptoms with 21 patients exhibiting GOS-sensitivity (>10 mm increase for overall symptoms). Of those, full-dose enzyme reduced overall symptoms (median 24. 5(IQR vs. 5.5( mm; P =0.006) and bloating (20.5( vs. 6.5(; P =0.017). Breath hydrogen production was minimal with no differences seen between placebo and full-dose ( P =0.597). Conclusions: Oral α-galactosidase taken with high GOS foods provides a clinically significant reduction in symptoms in GOS-sensitive individuals with IBS. This strategy can be translated into practice to improve tolerance to high GOS foods as an adjunct therapy to the low FODMAP diet.

Original languageEnglish
Pages (from-to)124-134
Number of pages11
JournalAmerican Journal of Gastroenterology
Issue number1
Publication statusPublished - 1 Jan 2018

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