To investigate the influence of different pre- and probiotics on faecal b-glucuronidase and b-glucosidase activity, as one of the claimed beneficial effects of pre- and probiotics is the hypothesis that these substrates are able to reduce the production of toxic and carcinogenic metabolites by suppressing specific enzyme activities in the colon. The effect was evaluated in a randomized, crossover study in 53 healthy volunteers who were randomly assigned to one of five treatment groups.

Animal studies suggest that prebiotics and probiotics exert protective effects against tumor development in the colon, but human data supporting this suggestion are weak. The objective was to verify whether the prebiotic concept (selective interaction with colonic flora of nondigested carbohydrates) as induced by a synbiotic preparation— oligofructose-enriched inulin (SYN1) + Lactobacillus rhamnosus GG (LGG) and Bifidobacterium lactis Bb12 (BB12)—is able to reduce the risk of colon cancer in humans.

Prebiotic inulin-type fructans are widely consumed in the diet and may have contrasting effects in Crohn’s disease by stimulating gut microbiota and/or by generating functional gastrointestinal symptoms. The aim of this study was to measure fructan and oligofructose intakes in patients with active and inactive Crohn’s disease compared with healthy controls.

Trompette et al. report that a diet rich in the fermentable fiber inulin and the associated metabolites—short-chain fatty acids—improve the response of mice to influenza infection by dampening deleterious immunopathology caused by neutrophils while enhancing anti-viral CD8+ T cell responses through a boost in T cell metabolism.

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in developed and developing countries. The use of synbiotics has been proposed as a probable management strategy for patients with NAFLD. We investigated the effects of synbiotic yogurt on hepatic steatosis and liver enzymes as primary outcomes and on oxidative stress markers, adipokine concentration, and gut peptide concentration as secondary outcomes in patients with NAFLD.