Insulin resistance and pancreatic-cell failure cause Type 2 Diabetes (T2D), which is a rapidly growing worldwide health concern. Multiple gut hormones and bacteria are involved in glucose homeostasis, and the gastrointestinal (GI) tract is considered as one of the primary regulating organs. Notably, the incretin hormone glucagon-like peptide-1 (GLP-1) produced by enteroendocrine L-cells plays a critical role in glucose homeostasis by eliciting pleiotropic effects mediated mostly through its receptor. As a result, targeting the GLP-1 signalling pathway as a therapeutic approach for T2D is quite appealing. Polyphenols, plant secondary metabolites, have caught a lot of attention recently because of their plethora of health advantages, including possible anti-diabetic properties. Dietary polyphenols, which are found in a variety of fruits, vegetables, and medicinal plants, may have anti-diabetic properties. Although the main targets and sites for polyphenolic compounds to perform anti-diabetic activity are yet unknown, the GI tract is the first organ to be exposed to these chemicals, where polyphenols may regulate enzymes and hormones. Indeed, new data suggests that polyphenols can increase GLP-1 production, indicating that these natural substances may have metabolic effects mediated at least in part by GLP-1.