On January 11, 1922, insulin was used for the first time to treat diabetes. Insulin was discovered by Sir Frederick G Banting, Charles H Best, and JJR Macleod at the University of Toronto. The discovery of insulin is considered as one of the greatest medical discoveries of the twentieth century. The treatment remains the only effective treatment for people with Type 1 diabetes today. A 14-year-old boy, Leonard Thompson was the first person to receive the medication to combat his Type 1 diabetes.