Insulin was discovered by Frederick Banting (1891–1941), John Macleod (1876–935), and Charles Best (1899–1978). Although earlier researchers had suspected that the pancreas secreted a substance that controlled the metabolism of sugar, it was not proved until 1922, when Banting, Macleod, and Best announced their discovery. The Nobel Prize in Physiology or Medicine in 1923 was awarded to Banting and Macleod. Banting shared his half of the prize with Best, while Macleod shared his half of the prize with James Bertram Collip (1892–1965), who had also collaborated with the team.