We usually think that the main role of glucagon is centered on gluconeogenesis, working in opposition to insulin to tightly control blood glucose. Glucagon is elevated in type 2 diabetes, and some of the clinical benefits of GLP-1 receptor agonists come from suppressing the effect of glucagon on gluconeogenesis. However, this Perspective published in Diabetes today shows that the impact of glucagon on amino acid turnover may be more primary than its impact on glucose. Amino acids stimulate pancreatic alpha-cells, which increase glucagon, which activates liver enzymes important in ureagenesis, thereby increasing degradation and disposal of amino acids. This could be important when considering the clinical impact of glucagon receptor antagonists for treatment of type 2 diabetes.