One hundred years of insulin

While John Macleod’s colleagues and students at the University of Toronto in Canada were planning their 1921 summer vacations, he was arranging to allocate some of his laboratory space to a freelance researcher. Although Frederick Banting’s project looked very speculative, Macleod offered him this opportunity and assigned a research student, Charles Best, to help him. Macleod then departed for Scotland, unaware that within three years he and Banting – but not best – would share a Nobel prize.

On returning to Canada in the autumn, Macleod realised Banting and Best were close to a breakthrough in treating diabetes – a condition studied for centuries, yet still incurable. Recognising the project’s importance, Macleod boosted it, and encouraged James Collip – a biochemist on research leave from the University of Alberta – to participate. After further laboratory work and some clinical trials, they announced the discovery of an effective remedy for diabetes. Within months a major drug company was mass-producing it, even though chemists needed many more years to unravel its molecular structure, and then to synthesise it.