Sir Frederick Grant Banting did not set out to change medicine forever. He was just a doctor in London, Ontario, looking for a way to help his patients. But in 1921, he and a medical student named Charles Best stumbled onto something massive. They found a way to extract insulin from the pancreas. This was the first effective treatment for diabetes.
Before this, diabetes was a death sentence. The disease causes glucose to build up in the blood at abnormal levels. Patients would waste away. There was no cure.
The story starts long before Banting touched a lab bench. In 1889, researchers Joseph von Mering and Oskar Minkowski removed the pancreas from dogs. The dogs developed severe diabetes instantly. Scientists guessed the pancreas made a hormone to control glucose. They called it “insulin.” But for years, no one could isolate it. The pancreas’s own digestive enzymes destroyed the insulin molecules as soon as they tried to grind the tissue up.
The Breakthrough in Toronto
Banting had an idea. He went to the University of Toronto in May 1921. He teamed up with Best, who was a medical student at the time. They worked in the labs of physiologist J.J.R. Macleod.
Their method was crude but brilliant. They tied off the pancreatic ducts in dogs. This stopped the digestive enzymes. It kept the pancreas inactive. But it preserved the islets of Langerhans. These cells were thought to make insulin.
They extracted solutions from these cells. They injected them into dogs that had already had their pancreases removed. The dogs recovered from their induced diabetes. The effect was quick.
Banting and Best proved they could isolate insulin in a form that worked consistently. It worked in humans too. This discovery allowed millions of people with diabetes to lead normal lives. They stopped dying from a condition that had no hope.
The Nobel Prize Controversy
The experiments finished in 1922. The results were undeniable. The next year, Banting and Macleod received the 1923 Nobel Prize for Physiology or Medicine.
This caused immediate anger. Macleod had not taken part in the original research. He was the lab head. He provided the space. He did not do the tying of ducts or the injections. Banting felt Best had been slighted.
Banting split his Nobel Prize money evenly with Best. He refused to let Best get nothing. Macleod shared his portion with James B. Collip. Collip was a young chemist. He helped purify the insulin.
Banting became head of the Banting and Best Department of Medical Research in 1923. He was made a knight of the British Empire in 1934.
His life ended abruptly in 1941. He was killed in a plane crash in Newfoundland. He was on a war mission. He was only 49.
The isolation of insulin remains one of the most significant medical achievements of the 20th century. It turned a fatal diagnosis into a manageable condition. The science behind how insulin regulates blood sugar is well understood today. But the raw determination of two men in a Toronto lab changed everything. We still rely on that discovery every day. The question is not if it worked. It is how many more breakthroughs are waiting for the next person willing to tie off a duct and try.
