The scientific rationale of recommendations in dietary fiber intake comes from the recognition of their benefits for health based on studies published many years ago. It remains unclear which key physiological effects are generated by dietary fiber in view of the diversity of the food components considered as dietary fiber, the relevance of their classification (soluble, insoluble), and from the recent discoveries putting forward their interactions with the gut microbiota.

The FiberTAG project will establish a set of biomarkers linking dietary fiber intake and gut-microbiota related health effect. We aim at refining the concept of dietary fiber based on novel biological effects that can occur upon gut microbiota-nutrients interaction by using existing cohorts and by developing innovative approaches to evaluate the health interest of novel insoluble dietary fiber.

Specific metabolites selected as biomarkers of microbiota-driven fermentation and gut-related functions will be analyzed in 5 existing cohorts of healthy or overweight populations in which the fecal microbiota composition and dietary fiber intake have been (or will be) analyzed. New intervention studies will be performed in healthy and cardiometabolic risk volunteers to evaluate the interest for health of two insoluble fibers (chitin-glucan and a wheat bran fraction).