Diabetes is recognized as one of the most common acromegaly co-morbidities with a prevalence ranging 20-53%, while over one-third of these patients have an altered lipid profile. In fact, as in the non-acromegalic population, carbohydrate and lipid metabolism abnormalities are closely linked. Long term exposure to an excess of growth hormone (GH) and Insulin-like growth factor-1 concentrations results in insulin resistance and an increased hepatic glucose production. The lipolytic effect of GH results in the mobilization of free fatty acids that further contributes to the decreased insulin sensitivity found in these patients. Some studies suggest that the presence of diabetes contributes to the increased mortality of acromegaly, although this remains controversial. Successful treatment of acromegaly usually results in significant, albeit incomplete improvements of the abnormal metabolic profile. © 2018 S. Karger AG, Basel.