On July 27, 1921, at the University of Toronto, Canadian scientists Frederick Banting and Charles Best successfully isolate insulin–a hormone they believe could prevent diabetes–for the first time. Within a year, the first human sufferers of diabetes were receiving insulin treatments, and countless lives were saved from what was previously regarded as a fatal disease.

Charles Best (left) and Frederick Banting

Charles Best (left) and Frederick Banting

Diabetes has been recognized as a distinct medical condition for more than 3,000 years, but its exact cause was a mystery until the 20th century. By the early 1920s, many researchers strongly suspected that diabetes was caused by a malfunction in the digestive system related to the pancreas gland, a small organ that sits on top of the liver. At that time, the only way to treat the fatal disease was through a diet low in carbohydrates and sugar and high in fat and protein. Instead of dying shortly after diagnosis, this diet allowed diabetics to live–for about a year.

Insulin and dog

A breakthrough came at the University of Toronto in the summer of 1921, when Canadians Frederick Banting and Charles Best successfully isolated insulin from canine test subjects, produced diabetic symptoms in the animals, and then began a program of insulin injections that returned the dogs to normalcy. On November 14, the discovery was announced to the world.


Two months later, with the support of J.J.R. MacLeod of the University of Toronto, the two scientists began preparations for an insulin treatment of a human subject. Enlisting the aid of biochemist J.B. Collip, they were able to extract a reasonably pure formula of insulin from the pancreases of cattle from slaughterhouses.


On January 23, 1921, they began treating 14-year-old Leonard Thompson with insulin injections. The diabetic teenager improved dramatically, and the University of Toronto immediately gave pharmaceutical companies license to produce insulin, free of royalties.


By 1923, insulin had become widely available, and Banting and Macleod were awarded the Nobel Prize in medicine.


Frederick G. Banting and John Macleod were awarded the Nobel Prize in Physiology or Medicine in 1923 "for the discovery of insulin."

Frederick G. Banting and John Macleod were awarded the Nobel Prize in Physiology or Medicine in 1923 “for the discovery of insulin.”

What is the impact of their work?  Although insulin doesn’t cure diabetes, it’s one of the biggest discoveries in medicine. When it came, it was like a miracle. People with severe diabetes and only days left to live were saved. And as long as they kept getting their insulin, they could live an almost normal life.  It is estimated that there are several hundred million people with diabetes who live as a result of the isolation of insulin in 1921.  It is probably one of the greatest medical breakthroughs in world history.


Born Today in History:

Peggy Flemming (July 27, 1948) Figure skater who won the only U.S. gold medal in the 1968 Olympics. Later, she publicly battled breast cancer, beating it with radiation therapy.

Died Today in History:

Bob Hope (May 29, 1903 – July 27, 2003) An entertainer and comic actor, known for his rapid-fire delivery of jokes and for his success in virtually all entertainment media.  Also known for his entertainment of the troops during World War II.


3 responses

  1. Insulin has saved so many and allowed them to lead normal, more healthy lives. It’s saving one of my cats, Nicky, who receives insulin shots 2x a day! But, boy, is it expensive. Seems every time I have to buy it, the price has gone up again… But, he’s been worth it! http://livingwithmyancestors.wordpress.com/2013/01/27/nicky-and-me/


    • Someone once told me that you can buy medical insurance for your pets. I don’t know how much it would be but maybe something to look into.


      • I checked into it years ago when my pets were still young (my work offered a program). Because I had so many animals, my premium would have been close to $500 mo. Figured if I had that kind of money to spend, I didn’t need insurance! But we manage! 🙂