Prebiotic effect of oligofructose after 2 weeks supplementation with a low dose: A randomized, double-blind, placebo-controlled, cross-over study

Inulin and oligofructose are prebiotic dietary fibers which affect gut microbiota and thereby host health. We aimed to demonstrate that 2.5 g/d oligofructose can lead to a significant increase in bifidobacteria thereby contributing to host health. 64 volunteers were randomized to consume 2.5 g/d Orafti (R) oligofructose or placebo for 14 days followed by a 4 week wash-out period and then crossed-over to the other intervention. Bifidobacteria and affect were assessed at the beginning and end of each intervention period. Furthermore, digestive function was documented daily. Bifidobacterium spp. increased significantly upon 2.5 g/d oligofructose intake compared to placebo (p = 0.016). Furthermore, stool frequency significantly increased during oligofructose compared to placebo (p = 0.0204) intake. With respect to affect, no significant changes were observed. This study is the first to demonstrate a significant increase in bifidobacteria coinciding with increased stool frequency after a very low dose of 2.5 g/d chicory oligofructose.