Efficacy, safety, and tolerability of fructooligosaccharides in the treatment of irritable bowel syndrome

Background: Interest in fructooligosaccharides as a health-promoting food c omponent is increasing. Fructooligosaccharides are mainly indigestible and large amounts in the colon may provoke gastrointestinal symptoms. Objective: The symptoms of irritable bowel syndrome (IBS) may be provoked b y large quantities of carbohydrates in the colon. The objective of this stu dy was to determine whether regular consumption of fructooligosaccharides w orsens gastrointestinal symptoms in patients with IBS. Design: A multicenter, prospective, randomized, double-blind, placebo-contr olled parallel group comparison was conducted at 24 sites. The study consis ted of a 2-wk, single-blind run-in phase and a 12-wk, double-blind comparat ive phase. Subjects were randomly assigned to receive 20 g fructooligosacch arides powder/d (n = 52) or a placebo (n = 46). Efficacy was based on the p atients' overall response to treatment at completion of the study and on th e severity and duration of individual symptoms (abdominal distension, abdom inal rumbling, abnormal flatulence, and abdominal pain). Results: Data from 96 patients (16 men and 80 women) were analyzed. After 4 -6 wk of treatment, IBS symptoms improved more in the placebo group than in the fructooligosaccharide group. After completion of the study, there were no significant differences between the 2 groups: symptoms improved in 58% of the fructooligosaccharide group and in 65% of the placebo group and symp toms worsened in 8% of the fructooligosaccharide group and in 13% of the pl acebo group. Conclusion: Although symptoms worsened in patients with IBS at the onset of treatment with 20 g fructooligosaccharides/d, continuous treatment for 12 wk resulted in no worsening of symptoms.