We propose the administration of insulin or secretagogues in pancreatic β-cell deficiency, thiazolidinediones, SGLT-2 inhibitors or GLP-1 receptor agonists in insulin resistance, and GIP/GLP-1 receptor agonists, GLP-1 receptor agonists or DPP-4 inhibitors depending on the body mass index and the associated risk of hepatic steatosis. Here, GIP is linked to fatty liver disease.