The two gut-derived hormones, glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1) are secreted from intestinal cells in relation to a meal and increase insulin secretion from the pancreas. The hormones also exert effects outside the pancreas, but especially for GIP, these are poorly investigated. Because of this, only GLP-1 based drugs (GLP-1 receptor agonists) are on the market for the treatment of type 2 diabetes and obesity. Nonetheless, a new drug is in clinical development: a combined GIP-GLP-1-receptor agonist (tirzepatide), which has shown better results than GLP-1 alone. The mechanism behind these impressive effects are unknown and in this study, the investigators will look into the exptrapancreatic effects of GIP and GLP-1, separate and combined and thus elucidate the mechanisms of action of this new drug class.