In the early 1920s, doctors knew diabetes was linked to a missing substance from the pancreas, but every attempt to extract it had failed. Frederick Banting, a young Canadian doctor, read a medical article by Moses Baron about what happens when the pancreatic duct is tied off. It gave him an idea for how to get the substance out before it was destroyed. Determined to test it, he talked it over with several people, and Professor J.J.R. Macleod at the University of Toronto gave him facilities to work. With a medical student named Charles Best as his assistant, Banting began the work that led to the discovery of insulin. Millions of lives followed from one man who read carefully and would not let a good idea go.
