Before insulin, a diagnosis of diabetes in a child was a sentence of death by slow starvation. Banting, with the student Charles Best, devised a way to extract the pancreas's internal secretion and so to lower the blood's deadly sugar.
In 1922 a purified extract turned Leonard Thompson, a public ward patient at Toronto General Hospital, away from the fatal chemistry of childhood diabetes; soon other starving children followed. Few discoveries have so swiftly turned a death sentence into a condition that could be argued with over time.