Insulin Discovered: A Cure for Diabetes Found

A struggling orthopedic surgeon and a twenty-two-year-old medical student extracted a substance from dog pancreases that would save more lives than most discoveries in the history of medicine. Frederick Banting and Charles Best isolated insulin at the University of Toronto, producing a pancreatic extract that dramatically lowered blood sugar in diabetic dogs, proving that the disease could be treated rather than merely managed through starvation diets. Diabetes was a death sentence in 1921. Type 1 patients, unable to produce insulin, wasted away regardless of treatment. The only therapy available was a severe caloric restriction diet developed by Frederick Allen, which slowed the progression but condemned patients to a life of near-starvation that often killed them almost as surely as the disease itself. Children diagnosed with diabetes typically survived less than a year. Banting conceived the idea of ligating, or tying off, the pancreatic duct to cause the organ's digestive cells to atrophy while preserving the islets of Langerhans, the cell clusters suspected of producing the unknown anti-diabetic factor. He persuaded University of Toronto professor J.J.R. Macleod to provide laboratory space and an assistant. Best, an undergraduate student, won a coin toss against another student for the position. Working through the summer, they produced a crude extract they called "isletin" that reduced blood sugar in pancreatectomized dogs. Biochemist James Collip joined the team to purify the extract for human use. The first injection was given to fourteen-year-old Leonard Thompson at Toronto General Hospital in January 1922. The initial dose caused an allergic reaction, but Collip's refined version, administered twelve days later, worked spectacularly. Thompson's blood sugar dropped to near-normal levels, and he lived another thirteen years. Banting and Macleod shared the Nobel Prize in 1923, and both divided their prize money with Best and Collip respectively, acknowledging the collaborative nature of the breakthrough that turned diabetes from a death sentence into a manageable condition.