Diabetes mellitus is a chronic metabolic disease. Multiple forms of diabetes have been identified, including type 1 (T1D) and type 2 (T2D). The former prevales in children and teenagers. It’s an autoimmune disease which leads to the destruction of the pancreatic insulin-producing cells resulting in a disturbed regulation of the blood glucose level. These patients have to self-inject insulin. Risk factors for type 2 diabetes are unhealthy nutrition, physical inactivity and overweight. The blood glucose level is elevated. Therefore, patients get medication and have to change their lifestyle.