Inflammatory bowel diseases (IBD) are chronic pathologies characterized by dysbiosis, defects in epithelial barrier function, and increased redox stress. Dysbiosis in IBD involves an expansion of Proteobacteria and a reduction of Firmicutes, which produce metabolites important in maintaining gut homeostasis. The epithelial NADPH oxidase dual oxidase 2 (DUOX2) catalyzes the production of hydrogen peroxide (H2O2) and is the only gene consistently altered in IBD patients in association with dysbiosis and before the onset of disease.