Inulin as a Modulator of the Intestinal Barrier: Experimental Evidence, Mechanisms and Clinical Implications

The intestinal epithelial barrier regulates paracellular transport, and its dysfunction is associated with inflammatory and metabolic diseases. Among dietary fibers, inulin has attracted considerable attention due to its beneficial effects on intestinal health. Inulin's actions have been attributed to protecting the structure and function of gut barrier components against inflammatory-associated damage. This review integrates preclinical and clinical studies evaluating the impact of inulin on intestinal permeability. Evidence from in vitro and in vivo models shows that inulin regulates the expression of tight junction proteins (TJPs), Paneth cell proliferation, and antimicrobial peptides, and modulates inflammatory signaling pathways. In addition, inulin prebiotic activity, via microbiota, stimulates the production of short-chain fatty acids (SCFAs) as butyrate that reinforces the barrier function. Understanding these pathways highlights the therapeutic potential of inulin as a nutritional strategy for treating barrier dysfunction. Clinical studies in obesity, metabolic disorders and inflammatory intestinal disease have associated inulin supplementation with improvements in biomarkers of intestinal permeability. Future studies are needed to test inulin's safety in order to prevent potential risks and hazards.