The Egyptians described diabetes 4,000 years ago and a Greek physician named the disorder some 2,000 years later, but how to control this devastating condition was unknown until Frederick G. Banting had an idea that led to the discovery of insulin in 1921.
 

In several magazine polls during his lifetime, Sir Frederick Banting was judged the most famous living Canadian. Co-discoverers of insulin, Banting and Professor J.J.R. Macleod of the University of Toronto were co-recipients of the Nobel Prize for Medicine in 1923. Banting, knighted in 1934, seven years before he tragically died in an airplane crash, was the first Canadian to be awarded a Nobel Prize. [The Toronto Star]

A part-time instructor at the University of Western Ontario’s medical school, Banting was preparing a lecture on the pancreas when he read that an American researcher had tied the pancreatic ducts of animals and found that, although the pancreas withered, the animals did not develop diabetes. He knew that the pancreas produces two secretions: one helps the body digest protein, starch and fat; the other is absorbed directly into the bloodstream. Banting wondered whether the blockage of the pancreatic ducts had stopped only the digestive secretions and whether the other secretions, possibly created by the spots on the pancreas known as the Islets of Langerhans, were still being produced. At 2:00 a.m. he wrote out his idea: “Ligate pancreatic ducts of dogs. Wait six or eight weeks. Remove the residue and extract.”

A week later he discussed his idea with a diabetes expert, Professor J.J.R. Macleod, head of physiology at the University of Toronto. Macleod was not impressed with Banting’s idea, asking frankly why he thought he had the answer when others far more experienced had failed.

Banting nonetheless persisted. He wrote a more detailed outline, and Macleod finally, in the spring of 1921, agreed to provide a laboratory. He also gave Banting two physiology graduate students to take turns doing the analytical work while he, himself, was vacationing in his native Scotland.

Banting, born on a farm near Alliston, Ontario, and a University of Toronto medical school graduate, began his work with Charles Best as his first assistant. The pancreatic ducts of some dogs were tied and in others removed to create diabetic animals.

Late in July an operation on a dog with tied ducts showed a pancreas about one-third normal size. It was removed and ground in a solution of sand and saline. The extract was then injected into a diabetic dog near death. The blood sugar decreased so dramatically that the dog lived weeks longer than expected.

When the other graduate student was unable to keep the commitment to replace Best, Best remained. He and Banting worked feverishly over the next two months to confirm their findings and improve the extract which they called “isletin.”

On returning from Scotland, Macleod was impressed but insisted they repeat their experiments to confirm that the results were consistent and that the extract proved beneficial over time. Also, another means of obtaining enough extract had to be found, and Banting recommended using the pancreas of unborn calves obtained from beef cattle at the local abattoir. This proved effective. Later, the glands of fully grown cows and pigs were used as they are today.
 

Professor J.J.R. Macleod, left, was a professor of physiology at the University of Toronto in 1923 when he was awarded the Nobel Prize along with Dr. Banting; assigned to work as an assistant with Dr. Banting in the spring of 1921, Charles Best was an integral member of the team discovering insulin. Banting shared his prize money with Best. Macleod, similarly, shared his prize money with J.B. Collip. [Dr. Charles Roland; NAC/C-37763]

Problems still remained. There was a need to improve the solvent used in the preparation of the extract in order to reduce its toxicity before it could be tested clinically. Moreover, if the extract was successful, how to mass produce it would be important since there were an estimated one million diabetics in North America.

Macleod, who renamed the extract “insulin,” enlisted the support of his staff, notably Dr. J. Bertram Collip, a University of Alberta biochemist then working with him, to find a less toxic and more effective product. Working with others, particularly the University of Toronto’s Connaught Laboratories, Collip produced a clinically acceptable insulin, and in January 1922, Banting was able to administer it to a patient, 14-year-old Leonard Thompson, whose health improved almost miraculously. Other diabetics were treated over the next several months with similar dramatic results.

Diabetes causes excessive thirst, urination, weight loss, fatigue and eventual emaciation, coma and death. Treatment with insulin corrects the body’s deficiency of this hormone. With daily insulin injections, patients recover their normal state; growth and vigor are regained.

The awesome success of insulin was first made known in medical journals based on remarks made by Professor Macleod. Some reports credited him with the discovery, implying that Banting and Best were assistants. Banting, already feeling that Macleod had taken over, resented the inference. When the Toronto Daily Star made the story public in a front-page article in March 1922, a subheading read “Banting Gives His All on the Result.”

From then on Banting’s name became synonymous with the discovery. This was later reinforced when Professor Macleod issued a statement indicating that reports crediting him with the discovery were wrong and that the idea was entirely Banting’s.
 

Before the discovery of insulin in 1921, juvenile diabetes was a dreaded and deadly disease. Made available in late 1922, insulin, a means of controlling this more serious form of diabetes, must be injected by syringe on a daily basis. While not a cure, insulin has saved the lives of millions worldwide. Banting did not take out a patent on insulin but assigned the rights to the University of Toronto. [Connaught Laboratories]

Honours were heaped on Banting. The University of Toronto made him a full professor of medical research and later established the Banting Institute in Toronto. Governments rewarded him with research grants, he was in great demand as a speaker, numerous medical societies presented him with medals, universities bestowed honorary degrees, and learned societies made him a member of their organizations. He was also the first Canadian to win the Nobel Prize (1923). Later he was knighted.

The fact that the Nobel Prize was shared with Professor Macleod didn’t please him as he felt it was Best who deserved this. Consequently, he gave half his prize money to Best; Macleod split his with Dr. Collip, a move later considered appropriate when it was realized all four had played a major role in the development of insulin.

Banting sold the patent to the University of Toronto for one dollar proposing that Connaught Laboratories produce the extract. They did, but the demand was so great that Eli Lilly Company (Canada) Limited, which had worked on the purification of the insulin in 1922, was awarded a contract and produced the first commercial supply in 1923. This company is today a major producer of insulin.

In 1928 Dr. Macleod returned to work in Scotland. Dr. Collip was later Dean of the University of Western Ontario’s medical school and Charles Best, graduating in medicine in 1925, served as chairman of the University of Toronto’s physiology department from 1929 to 1965. Dr. Banting continued to do research but also spent much of his time encouraging young scientists with their discoveries.

At the outbreak of World War II, Banting succeeded in assisting an RCAF doctor, W.R. Franks, to develop the world’s first anti-G suit designed to prevent pilots from blacking out. Asked to conduct research on seasickness, Banting boarded a bomber flying to England but, tragically, died of a punctured lung when the plane crash-landed near Musgrave Harbour, Newfoundland, in February 1941.