As incretin-based therapeutics, such as GLP-1 receptor (GLP-1R) agonists and dipeptidyl peptidase-4 inhibitors (DPP-4i), are commonly used for treatment of type 2 diabetes, our observation that IF can physiologically increase GLP-1 levels suggests a possibility that IF can be a lifestyle supplement to existing diabetes treatments by increasing the efficacy or reducing the dosages. Here, DPP4 is linked to type 2 diabetes mellitus.