Abstract
The year 2022 marked the one-hundredth anniversary of the first application of insulin. November 14th, the birth date of one of its main discoverers, Frederick Banting, was designated as World Diabetes Day. This paper comprises a narrative review of the history of the discovery of diabetes and insulin, progress in insulin development, important breakthroughs in insulin production and delivery, and a short commentary regarding potential future developments in insulin treatment. Diabetes, as one of the earliest recorded illnesses in medical writings, has been a focus of research for almost the entire written human history. Groundbreaking discoveries during the early 20th century have resulted in type 1 diabetes mellitus becoming a treatable, chronic condition. The relationship between good glycemic control and reduced occurrence of diabetes complications was established, which has enticed further development and refinements in insulin treatment, ranging from the purification and increased quality of insulin itself, as well as various inventions in its administration. Despite great achievements in insulin therapy so far, future research aims to avoid the need for subcutaneous administration and to create non-invasive means of insulin application.