Zonulin is a protein that regulates the opening of tight junctions between intestinal cells - essentially the gate control for gut permeability. Discovered by Dr. Alessio Fasano elevated zonulin levels are the primary clinical marker of increased intestinal permeability. Zonulin is triggered by gliadin (a wheat protein) and certain harmful bacteria. It is now used as a biomarker for gut barrier health and is a focus of research into celiac disease, type 1 diabetes, multiple sclerosis, and IBD.
