Table of Contents
- Introduction
- Diabetes Before 1921
- The State of Medical Science in the Early 20th Century
- Who Were Frederick Banting and Charles Best?
- The Research Begins in Toronto
- The Role of John Macleod and James Collip
- First Successful Insulin Injection
- Early Human Trials and Public Reception
- Mass Production and Commercialization
- Ethical Considerations and Patent History
- Global Impact on Diabetes Management
- The Nobel Prize and Scientific Legacy
- How Insulin Continues to Evolve
- Conclusion
- External Resource
- Internal Link
1. Introduction
On July 27, 1921, a scientific breakthrough in Toronto, Canada, would change the course of medical history and give new hope to millions. Two researchers, Frederick Banting and Charles Best, discovered a hormone secreted by the pancreas that could regulate blood sugar. This molecule, later named insulin, transformed diabetes mellitus from a death sentence into a treatable condition.
Before this momentous day, a diagnosis of diabetes—especially type 1—meant inevitable decline and death. But this discovery reshaped modern endocrinology and has saved countless lives ever since.
2. Diabetes Before 1921
In the early 20th century, diabetes was a dreaded disease. Doctors had few tools to combat it. The main symptom—extreme thirst and urination—was often accompanied by rapid weight loss and fatigue. Starvation diets were the only “treatment,” which prolonged life slightly but with misery.
Patients, often children or young adults, would waste away, slipping into comas caused by dangerously high blood glucose levels. The underlying biological mechanism was not fully understood, and autopsies of diabetic patients often showed damage to the pancreas.
3. The State of Medical Science in the Early 20th Century
Science was beginning to piece together the puzzle. Researchers knew that the pancreas played a key role in regulating sugar metabolism. In 1869, Paul Langerhans had discovered clusters of cells in the pancreas, later called the islets of Langerhans.
In the 1880s and 1890s, experiments in dogs and other animals suggested that removal of the pancreas induced diabetes. However, no one had been able to isolate and purify the hormone responsible. The task was both scientifically challenging and biologically fragile.
4. Who Were Frederick Banting and Charles Best?
Frederick Banting was a Canadian doctor with a keen interest in research but no significant lab experience. Charles Best, a young medical student, became his assistant. The pair began their experiments in the lab of John Macleod, a prominent physiologist at the University of Toronto.
Banting had read articles suggesting that ligating (tying off) the pancreatic ducts might allow the islets of Langerhans to remain intact while the rest of the pancreas atrophied, simplifying extraction of the hormone.
5. The Research Begins in Toronto
Their first experiments began in May 1921. Using dogs whose pancreases had been surgically modified, Banting and Best sought to create a diabetes model and then treat it with pancreatic extracts.
The real breakthrough came in late July when they injected a diabetic dog with a crude extract. The animal’s blood sugar levels dropped. The hormone from the islets was working. It could control glucose—exactly what diabetic patients lacked.
6. The Role of John Macleod and James Collip
While Banting and Best deserve credit for the early success, John Macleod and biochemist James Collip played essential roles. Macleod provided facilities, oversight, and credibility. Collip helped purify the extract, making it suitable for human use.
This teamwork—though later mired in disputes—was critical. By late 1921, the team had developed a relatively stable preparation of insulin that could be administered to humans.
7. First Successful Insulin Injection
In January 1922, the first human patient received insulin: Leonard Thompson, a 14-year-old boy with type 1 diabetes, who was near death. After the initial crude injection caused an allergic reaction, Collip refined the extract.
The second injection, on January 23, worked.
Leonard’s blood sugar dropped. His symptoms improved. He lived another 13 years—unheard of for a child with type 1 diabetes at the time.
8. Early Human Trials and Public Reception
The success was immediate and overwhelming. Soon, other diabetic patients began receiving insulin injections. Their recoveries were dramatic and emotional. Entire wards of children were brought back from the brink of death.
News spread rapidly. Headlines praised the “miracle cure.” Parents, physicians, and scientists around the world followed the news with hope and wonder.
9. Mass Production and Commercialization
To meet growing demand, the team partnered with Eli Lilly and Company in the U.S. to produce insulin at scale. By 1923, insulin was being manufactured and distributed to hospitals globally.
The commercial success was tempered by altruism: Banting, Best, and Macleod sold the patent for $1 to ensure it would remain widely available.
10. Ethical Considerations and Patent History
Banting and Best believed that medical breakthroughs should benefit everyone. They famously refused to profit from their work. Their decision set a moral precedent in medical science, though later decades saw pharmaceutical companies reaping large profits from insulin.
Today, insulin pricing remains controversial, especially in the U.S., where patients sometimes ration insulin due to cost.
11. Global Impact on Diabetes Management
Insulin remains the gold standard for type 1 diabetes and is also used in type 2 diabetes when oral medications fail. The discovery transformed life expectancy and quality of life for millions.
Beyond diabetes, insulin research led to better understanding of hormones, metabolism, and even molecular biology. It’s considered one of the greatest medical breakthroughs of the 20th century.
12. The Nobel Prize and Scientific Legacy
In 1923, Banting and Macleod were awarded the Nobel Prize in Physiology or Medicine. Banting shared his prize money with Best; Macleod did the same with Collip.
While tensions persisted among the team, their contribution to science remains unshaken. Today, World Diabetes Day is celebrated on November 14, Banting’s birthday.
13. How Insulin Continues to Evolve
Modern insulin is produced via genetic engineering, using bacteria or yeast to manufacture identical human insulin. Various analogs have been developed—fast-acting, long-acting, and combinations.
The goal is tighter glucose control, fewer injections, and better outcomes. Insulin pumps, continuous glucose monitors, and potential artificial pancreas systems all owe their existence to the work begun in 1921.
14. Conclusion
The discovery of insulin on July 27, 1921, wasn’t just a scientific triumph—it was an act of profound humanity. It gave diabetic patients a second chance at life and taught the world that compassion and science can coexist.
From a small lab in Toronto to hospitals across the world, insulin continues to be a beacon of hope, a testament to curiosity, collaboration, and care.
15. External Resource
Wikipedia – Discovery of insulin
