The 1923 Nobel Prize for Insulin

Category	Research
Also known as	insulin Nobel Prize, Banting Macleod Nobel
Last updated	2026-04-14
Reading time	3 min read
Tags	historynobel-prizeinsulindiabetes

Overview

The 1923 Nobel Prize in Physiology or Medicine was awarded jointly to Frederick Banting and John James Rickard Macleod "for the discovery of insulin." The prize, awarded less than two years after the clinical introduction of insulin therapy, remains one of the most rapid recognitions of a biomedical discovery in the history of the Nobel awards.

The nomination reflected the dramatic clinical impact of insulin. By 1923, children dying of diabetic ketoacidosis in Toronto, Boston, and elsewhere were being rescued by injections of a substance that had been completely unknown to medicine only two years earlier. The Nobel Committee responded unusually quickly to this transformation of a uniformly fatal disease into a manageable chronic condition.

The decision to award the prize only to Banting and Macleod, and not to Charles Best or James Collip, provoked controversy that has never fully settled. Banting reportedly considered refusing the prize because of Best's exclusion, and ultimately announced that he would share his half of the prize money with Best. Macleod, in turn, shared his half with Collip.

Key People

Frederick Banting (1891–1941): Canadian surgeon and co-recipient.
J.J.R. Macleod (1876–1935): Scottish-born Canadian physiologist and co-recipient.
Charles Best (1899–1978): Medical student whose role in the discovery was not formally recognized by the Nobel.
James Collip (1892–1965): Biochemist who purified insulin for clinical use; also not formally recognized.
Nicolae Paulescu (1869–1931): Romanian physiologist whose prior work on pancreine has continued to generate debate about Nobel priority.

Timeline

1921: Banting and Best begin insulin research in Toronto.
1922: Leonard Thompson becomes the first patient successfully treated.
1923: Insulin is licensed to Eli Lilly; Banting and Macleod are awarded the Nobel Prize on October 25.
1924: Nobel lecture is given by Macleod in Stockholm.

Background

The speed of the award reflected the combination of clinical need and compelling mechanism. Type 1 diabetes before 1922 was a disease of emaciation and early death, and insulin's effects were immediately visible. The Toronto team's willingness to license the discovery to Eli Lilly for a symbolic fee, rather than seek private profit, also helped the therapy reach patients quickly and bolstered public and scientific support for the award.

The controversy about who should have received the prize reflects how laboratory science had become in 1921. Banting's insight, Best's technical skill, Macleod's institutional support, and Collip's purification chemistry were all necessary; no single member of the team could have produced insulin alone. The Nobel tradition of recognizing at most three people per prize proved ill-suited to the realities of modern biomedical research, a limitation that has persisted ever since.

Modern Relevance

The 1923 Nobel is an enduring touchstone for several reasons. It established the tradition of rapid recognition for translational breakthroughs — a tradition the Nobel Committee has sometimes followed and sometimes not. It also illustrates the limits of the three-person rule: Best and Collip's contributions remain central to any honest account of the discovery, and yet neither received the prize.

Today, insulin therapy has evolved through recombinant human insulin, insulin analogs, and closed-loop delivery systems. The 1923 Nobel marks the beginning of this lineage. For more on the science, see banting-best-insulin and insulin-structure-solved.