Diabetes is an epidemic of global scale with an estimated 8.8 % of the global population suffering from this disease in 2015 and an estimated 5 million diabetes related deaths that year. The estimated global health expenditure for diabetes in 2015 was 673 billion dollars, corresponding to roughly 12 % of the overall budget. The majority of those costs are for the treatment of diabetes related complications. These complications often occur due to the incorrect dosage of diabetes medication. Both, chronically elevated blood glucose (BG) levels (hyperglycemia) due to underdosing, as well as dangerously low BG levels (hypoglycemia) due to overdosing should be avoided. Because of the high risk of hypoglycemia the correct dosing of insulin in type 1 diabetes mellitus (T1DM) is an especially challenging task. The immense interpatient and intrapatient variability in insulin needs asks for an adaption of treatment doses on a daily basis. For each meal an adequate dose of fast-acting insulin has to be injected to counteract the effect of the meal carbohydrates on the BG level (known as a ?meal bolus?).