The discovery of insulin at the University of Toronto in 1921-22 was one of the most dramatic events in the history of medicine. It marked a turning point in the treatment of diabetes, a condition that had previously been a death sentence for many. Insulin’s impact was sensational because of the incredible effect it had on diabetic patients. Those who watched the first starved, sometimes unconscious, diabetics receive insulin and return to life witnessed one of the genuine miracles of modern medicine. It was considered the closest approach to the resurrection of the body that our secular society can achieve. The discovery of insulin quickly became the elixir of life for millions of people worldwide.
The key figure behind this monumental discovery was Frederick Grant Banting, born on November 14, 1891, on a farm near Alliston, Ontario. Banting grew up in a close-knit, rural community as the youngest of five children in a hardworking Methodist family. His early life was spent enjoying a normal farm boyhood, where he developed a strong connection with nature and animals. Despite being a serious-minded but average student in school, Banting was determined and resilient, qualities that would later prove vital in his medical career.
Initially unsure of his path, Banting considered the Methodist ministry, but eventually dropped out of an arts course at the University of Toronto and re-enrolled in the university’s prestigious medical program in 1912. Though his academic performance remained average, Banting excelled in athletics and demonstrated a strong sense of determination. His studies were interrupted by World War I, during which he served as a medical officer in the Canadian Army, earning the Military Cross for bravery under fire. This experience deepened his commitment to medicine and sparked his interest in medical research.
After the war, Banting struggled to find success in private practice but began to focus on research, particularly on diabetes and the pancreas. Inspired by an article he read on the pancreas in 1920, Banting developed a new approach for isolating the “internal secretion” of the pancreas, which he believed could control blood sugar levels. He proposed his idea to J.J.R. Macleod, a professor of physiology at the University of Toronto. Although initially skeptical, Macleod provided Banting with a lab, some dogs for experimentation, and a young assistant, Charles Best, to help him with his experiments.
A Mysterious Something
In early January 1922, J.B. Collip expressed both excitement and cautious optimism when he said, “We have obtained from the pancreas of animals a mysterious something which, when injected into totally diabetic dogs, completely removes all the cardinal symptoms of the disease… If the substance works on the human, it will be a great boon to Medicine.” Collip’s words captured the potential that insulin held as the team at the University of Toronto pressed forward with their research.
Following an intense summer of experiments, Frederick Banting and Charles Best had proven their approach in lowering blood sugar in diabetic dogs, yet much work remained. As they transitioned into the winter months, John Macleod ensured that their research continued by securing laboratory space and providing necessary resources. Despite some early tension, Macleod supported the project, even arranging retroactive pay for Banting and Best to recognize their progress. Banting, who had struggled financially, was relieved to receive a position as a lecturer in Pharmacology, which allowed him to focus on the research. His experiments could continue, but questions about the exact direction of the work remained.
While Banting had ambitious ideas about expanding the scope of the experiments, Macleod advised sticking to the core problem at hand: isolating the internal secretion of the pancreas. He suggested that the work remain primarily in the hands of Banting and Best until they had definitive results, despite Collip’s offer to assist. The research advanced methodically, with experiments focusing on controlling variables such as diurnal blood sugar fluctuations in diabetic dogs. As they prepared pancreatic extracts from ligated dogs, they were getting closer to confirming that their “mysterious something” could indeed hold the key to controlling diabetes.
This careful, step-by-step approach culminated in their breakthrough in 1922, when they successfully administered insulin to humans, marking the start of a new era in diabetes treatment.
The First Human Trials
By the winter of 1921-22, Banting and Best were ready to test their extract on humans. Leonard Thompson, a young boy at Toronto General Hospital, became the first human diabetic to receive insulin. The results were miraculous, as insulin saved Thompson’s life. This success led Macleod to put his entire laboratory to work on insulin production. With the help of James Collip, the team purified the extract, making it suitable for broader use.
One of the most famous early insulin patients was Elizabeth Hughes, the daughter of U.S. Secretary of State Charles Evans Hughes. Elizabeth had survived through starvation therapy and was severely malnourished when she received insulin treatment. Her dramatic transformation, captured in “before and after” photographs, shows her gaunt appearance prior to insulin and her healthy state just months later. These images have become iconic, representing the life-saving potential of insulin.
Global Impact and Legacy
The discovery of insulin was such a significant advancement that Banting and Macleod were awarded the Nobel Prize in Medicine in 1923. In a gesture that reflected the collaborative nature of the discovery, Banting shared his prize with Best, and Macleod shared his portion with Collip, acknowledging their vital contributions. To further emphasize the humanitarian spirit of the discovery, Banting, Collip, and Best sold the insulin patent to the University of Toronto for just $1, ensuring that this life-saving treatment could be made widely available.
With the assistance of the pharmaceutical company Eli Lilly and Company, insulin was soon produced in commercial quantities. By 1923, insulin was available in virtually unlimited amounts, saving thousands of diabetics around the world. The development of insulin as a treatment for diabetes remains a landmark achievement in medical history, revolutionizing diabetes care and transforming what was once a fatal condition into a manageable disease.
The “before and after” photos of children treated with insulin, such as the transformation of young diabetic patients from a state of severe malnutrition to restored health, serve as powerful examples of insulin’s life-saving impact. These images reflect the profound shift in how diabetes could be treated and managed.
The discovery of insulin continues to stand as one of the most extraordinary achievements in medical history. Its influence not only revolutionized diabetes care but also set the stage for modern approaches to treating chronic diseases, benefiting millions of people across the globe.