2021 marks the 100th anniversary of insulin’s discovery

Cellaviva Danmark - June 7, 2021

From the journal Allt om Diabetes, no. 1 2021

2021 marks the 100th anniversary of insulin's discovery

The discovery of insulin is one of the great medical breakthroughs of the 20th century. The miracle of Toronto in 1921 miraculously saved the lives of millions of people with diabetes. One of the world’s most dreaded diseases could suddenly be treated.

Insulin is not just a drug. The hormone is the difference between life and death for those who have been unlucky enough to suffer from type 1 diabetes. Before insulin, doctors were powerless when the lives of children and young people slipped through their hands. The only thing they could offer were heartbreaking starvation diets or disgusting fat treatments that could give the sick a few weeks, at best a year or so, in the vague hope that something new would emerge.

Anyone who wants to believe in miracles must dare to be a fool. Once the insulin was trapped in a syringe, it could with an injection take the dying person out of the sugar coma and back to life. It was considered nothing less than a miracle cure.

The discovery of insulin was a revolution. But no coincidence. Diabetes is one of the most studied diseases in medical history. In the years around the turn of the century, both diabetes and healing gland extract were hot areas of research, and the elixir hunters were numerous. During the first decades of the 20th century, approx. 400 attempts to extract the mysterious, antidiabetic drug suspected of being present in the pancreas. The dilemma was that the gland also secretes pancreas whose enzymes were mixed with and destroyed the insulin before the researchers could use it.


Frederick Banting

The idea came to Frederick Banting, a young surgeon in Toronto who one evening read about the pancreas: if the pancreas is constricted, the enigmatic substance can be isolated – and diabetes can be cured. He had never studied diabetes or cared for a diabetic patient. When Banting presented his ideas to Canada’s leading diabetes researcher John Macleod, he very much doubted that the inexperienced optimist could achieve success where experts had failed. The stubborn Banting did not give up. He finally got ten dogs, a worn down lab in the attic and an assistant, 21-year-old Charles Best. “Errors are also important results,” Macleod reasoned, giving them some hot summer months in 1921 to test their theory.

In the beginning, the experiments were catastrophic. Banting’s and Best’s attempt was to operate on a twisted pancreas from dogs and extract an extract for injection in dogs that had become diabetic without their gland. Most of them died of the operation or of infections afterwards. By mid-summer, the result was a long line of dead dogs.

But on dog 410, blood sugar really dropped before it died. Banting and Best had found their insulin. On August 1, their glandular juice managed to wake dog 406 from a deep coma. Soon they began to learn how to dose the composition. In the late fall, Banting and Best were able to keep the dog Marjorie alive and in good health for 70 days with daily insulin injections. The dog died while the extract was used. The success was within reach.

Banting’s chief professor Macleod and chemist James Collip joined the team in December and steered the scientific mess of amateurs. Collip extracted a cleaner insulin and calculated doses. He also solved the problem of lack of canine insulin by fetching pig and beef glands from the local butcher. The volume of insulin multiplied. They were ready to test on humans.

On January 11, 1922, Leonard Thompson became the first patient to be injected with insulin. He was 14 years old, weighed 29 kg and died of type 1 diabetes at Toronto Hospital when he received the famous dose. In two hours, his dangerously high blood sugar dropped to almost a normal level. “The boy became more alert, seemed to feel better and even said he felt healthier,” Banting noted. Although he had an allergic reaction to the first injection, Thompson regained his strength quickly. Within a few days, six terminally ill children received injections with the same dizzying results.


The Miracle of Toronto

News of the Toronto miracle spread like wildfire around the world. The pharmaceutical company Eli Lilly was involved in the production of insulin on a large scale. The Danish Nobel prize winner August Krogh, who visited Macleod’s laboratory, brought the method home to Denmark and started insulin production as early as March 1923. At the same time, the insulin reached Sweden’s hospital wards. Grieving families saw their children saved back to life from the edge of the grave, the same year that Banting and Macleod received the Nobel Prize for their discovery in Stockholm in 1923.



Text: Ulrika Lundberg

Allt om diabetes is the Swedish Diabetes Association’s membership magazine, which is published 6 times a year.

You can find the article in its entirety here: https://www.diabetes.se/aktuellt/fokus/ja-ma-vi-leva/