Charles Herbert Best (February 27, 1899, to March 31, 1978) was the University of Toronto physiologist who, as a student assistant in 1921 and 1922, worked beside Frederick Banting on the extract that became insulin. He went on to direct insulin production at the Connaught Antitoxin Laboratories, to chair the university’s physiology department from 1929, and to lead the Banting and Best Department of Medical Research after Banting died in 1941.
Best was born in Maine, the son of a Canadian-born country doctor, and spent almost all of his working life in Toronto. The Dictionary of Canadian Biography treats him as a central figure in the city’s medical science, and also as a man whose later accounts of the insulin story do not always match the primary records.
Life in brief
| Item | Detail |
|---|---|
| Born | February 27, 1899, Pembroke, Maine (Dictionary of Canadian Biography); West Pembroke, Maine (Royal Canadian Institute) |
| Died | March 31, 1978, Toronto (Dictionary of Canadian Biography) |
| Parents | Herbert Huestis Best, a Canadian-born country doctor practising in Maine, and Luella May Fisher |
| Role | Physiologist, professor, and director of medical research |
| Toronto connection | Student and professor at the University of Toronto, insulin work in 1921 and 1922, Connaught Antitoxin Laboratories, Banting and Best Department of Medical Research |
| Married | September 3, 1924, Toronto, to Margaret Hooper Mahon; two sons |
From Maine to University College
According to the Dictionary of Canadian Biography, Best was the second child and only son of Herbert Huestis Best and Luella May Fisher. Best entered the University of Toronto in 1916. In his second year he moved into the honours course in physiology and biochemistry, the field that would shape the rest of his career.
The First World War interrupted his studies. He joined the Canadian army late in the war but did not reach the front. He finished his bachelor of arts in the spring of 1921, a few weeks before the work that made his name began. An M.A. followed in 1923, a medical degree about 1925, and a D.Sc. from the University of London in 1928.
The summer of 1921 at the university
In 1921 J. J. R. Macleod, the University of Toronto’s professor of physiology, assigned two recent graduates, Best and his friend E. Clark Noble, to assist Frederick Banting with experiments on dogs whose pancreas had been removed. The University of Toronto’s insulin history page says experiments with depancreatized dogs began on May 17, 1921, and that the first clear success came on July 30, when an extract lowered the blood sugar of a dog known as Dog 410.
The University of Toronto’s insulin history page repeats the story that Best and Noble tossed a coin to decide who would work with Banting first, and that Best won; the page words it as an allegation. The Dictionary of Canadian Biography describes Best’s role more modestly: he was a student assistant who ran blood-sugar and other biochemical tests and helped with the surgery on the dogs, while Banting was the senior partner. Best’s name appeared on the published research papers.
Insulin production at Connaught
The work moved quickly from the laboratory to patients. On January 25, 1922, Best signed an agreement to work under Macleod’s direction. When the biochemist J. B. Collip, who had been brought in to purify the extract, left in the spring of 1922, Best became director of insulin production at the Connaught Antitoxin Laboratories. The University of Toronto page gives his age at that point as 23 and notes that he also acted as a link between Connaught and the pharmaceutical firm Eli Lilly in Indianapolis. The Royal Canadian Institute dates his directorship of the insulin division to shortly after his M.A. in 1923, a small difference from the 1922 date used by the university and the Dictionary.
The article on Frederick Banting follows the other half of the partnership. This page concentrates on Best’s own career.
The Nobel Prize and who shared it
The 1923 Nobel Prize in Physiology or Medicine went to Banting and Macleod. Best was not named. According to the Dictionary of Canadian Biography, Banting shared his prize money with Best, and Macleod shared his with Collip. The University of Toronto adds that Best was lecturing at Harvard on October 26, 1923, when he learned of the award. The Dictionary of Canadian Biography quotes a telegram in which Banting ascribed to Best an equal share in the discovery.
The question of credit remained sensitive. The Dictionary of Canadian Biography states that Best’s later accounts of the discovery claimed an equal partnership with Banting and played down the contributions of Macleod and Collip, and that those accounts are not consistent with the primary sources. Readers who want the documents themselves can use the University of Toronto’s insulin collection, listed below.
Professor and department head
After study in England he returned to Toronto as an assistant professor, and the Dictionary of Canadian Biography dates this to the year before his 1928 doctorate. In 1929 he succeeded Macleod as professor and chairman of the department of physiology. His research ranged across choline, the physiology of Olympic athletes, and the purification of heparin, an anticoagulant. A textbook, The Physiological Basis of Medical Practice, appeared under his name with Norman Burke Taylor, a member of his department who, the Dictionary says, wrote most of it.
Two campus buildings carry the story in stone. The Banting Institute was named in 1930, and the Charles H. Best Institute opened in 1953 next door, according to the Dictionary. The Dictionary of Canadian Biography gives no street address for either, so this article does not either.
The war years and the Banting and Best Department
Banting died on February 21, 1941, in the crash of a bomber flown to Britain, and the Dictionary of Canadian Biography says Best was appointed his successor as director of the department of medical research, which gradually evolved into the Banting and Best Department. According to the University of Toronto, Best had already launched the Canadian Blood Serum Project in 1939 to produce dried human serum for military use. In 1942 he took charge of the Royal Canadian Navy’s medical research unit and in 1943 was promoted to Surgeon Captain. The Dictionary of Canadian Biography adds that his wartime work covered blood transfusion services and, for the navy, night vision and motion sickness.
The Dictionary names him as one of the founders of the Canadian Diabetes Association. It also records that in the early 1960s stressful events brought on clinical depression severe enough to need electroshock therapy, after which Best gradually slipped into retirement. The Dictionary gives no retirement year.
Timeline
- 1899: born in Maine.
- 1916: enters the University of Toronto.
- 1921: bachelor’s degree; insulin experiments begin May 17 with Banting.
- 1922: becomes director of insulin production at Connaught.
- 1923: Banting shares Nobel prize money with him.
- 1929: becomes professor and chairman of physiology.
- 1941: succeeds Banting as director of medical research.
- 1953: Charles H. Best Institute opens.
- Early 1960s: depression; gradual retirement afterward (no year given).
- 1978: dies in Toronto.
Death and what remains disputed
Best died in Toronto on March 31, 1978. According to the Dictionary of Canadian Biography, his son Sandy had died suddenly that March at age 46, and Best collapsed and died in hospital a few days later. The birthplace is given two ways in the sources: Pembroke (Dictionary of Canadian Biography) and West Pembroke (Royal Canadian Institute), both in Maine.
Frequently asked questions
Did Charles Best win a Nobel Prize?
No. The 1923 prize in Physiology or Medicine went to Frederick Banting and J. J. R. Macleod. Banting shared his prize money with Best.
What did Best do in the insulin discovery?
He was a student assistant in the summer of 1921. The Dictionary of Canadian Biography says he ran blood-sugar tests and helped with surgery on the dogs. In 1922 he took over insulin production at Connaught.
Where was Charles Best born?
In Maine, to Canadian parents. The Dictionary of Canadian Biography says Pembroke and the Royal Canadian Institute says West Pembroke.
What is the Charles H. Best Institute?
A University of Toronto research building that opened in 1953 beside the Banting Institute. Check the university for what it houses today.
Last verified: October 2026
Sources
- Dictionary of Canadian Biography, “Best, Charles Herbert,” vol. 20
- University of Toronto Libraries, “The Discovery and Early Development of Insulin,” page on Charles Best
- Parks Canada, “Discovery of Insulin National Historic Event”
- Dictionary of Canadian Biography, “Banting, Sir Frederick Grant,” vol. 17
- Royal Canadian Institute for Science, “Charles H. Best (1899-1978),” 100 Lives
Related reading
- Frederick Banting, the surgeon who started the insulin project
- The University of Toronto and its history
- An overview of Toronto’s history
- Toronto timeline of key dates
- People of Toronto history
Cite this page
APA: History of Toronto. (2026, October 23). Charles Best: The Toronto Scientist Behind Insulin. https://historyoftoronto.ca/blog/charles-best
MLA: “Charles Best: The Toronto Scientist Behind Insulin.” History of Toronto, 23 Oct. 2026, https://historyoftoronto.ca/blog/charles-best. Accessed .
Chicago: History of Toronto. “Charles Best: The Toronto Scientist Behind Insulin.” Last modified October 23, 2026. https://historyoftoronto.ca/blog/charles-best.
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