Inadequate dietary fiber intake contributes to the prevalent irregularity and constipation in Western countries. Although eating adequate amounts of fibers from fiber-rich foods, foods with added fibers and dietary fiber supplements is considered the first option for improving laxation, the efficacy can vary among types of fibers. The present study is a randomized control trial that included healthy adult participants with ≤3 bowel movements/week and a habitual low dietary fiber intake in a parallel design to evaluate the benefits for laxation by supplementing the daily diet with oligofructose (Orafti® P95; OF), a fermentable source of fiber and established prebiotic (n = 49); maltodextrin was the placebo (n = 48). After a run-in phase, OF was initially provided at 5 g/day, then increased to 10 and 15 g/day with four weeks for each phase. Stool frequency (bowel movements per week) for the OF and maltodextrin (MD) groups were initially similar (3.98 ± 1.49 vs. 4.06 ± 1.48), did not change for the placebo group, but increased for the OF group with the difference significant at 15 g/day (p = 0.023). Stool consistency was similar and remained unchanged at all doses for both groups. Gastrointestinal sensations were low for both groups. Laxation benefits were especially pronounced for participants with >13 g/day habitual dietary fiber intake, with significant laxation at 10 g and 15 g OF/day (p = 0.04 and p = 0.004, respectively) A daily supplement with a short-chain inulin-type fructan derived from chicory roots, i.e., oligofructose (Orafti® P95) provided a laxation effect without causing gastrointestinal (GI) distress for healthy participants with irregularity associated with low dietary fiber intake.
Keywords: clinical trial; constipation; fermentable; fiber; fructan; inulin; irregularity; laxation; supplement.