WORCESTER, Mass. - Tuesday marks the 100th anniversary of the first insulin injection used to treat diabetes. 

The Diabetes Center of Excellence at UMass Chan Medical School says by the early 1920s, researchers suspected diabetes was caused by a malfunction in the digestive system... 

But the only way to treat it was through diet.  People typically didn't live long after a diagnosis. 

The center’s co-director, Dr.  David Harlan, said researchers had successfully tested insulin on animals and on Jan. 11, 1922, 14-year-old Leonard Thompson became the first person to receive an insulin injection for diabetes. 

Thompson improved dramatically after receiving a second shot, and the University of Toronto immediately gave pharmaceutical companies license to produce insulin.

“Insulin has led to so many advances in modern medicine. It really was the advent of modern molecular biology and molecular medicine revolution. Insulin was the first substance made in bacteria that we use to treat humans,” Dr. Harlan said. “All of the commercials you see on tv about various antibodies all stem from the research done to teach bacteria to create human insulin. It's really a remarkable story."

The creators of insulin,  Frederick Banting and Charles Best,  were awarded the Nobel Prize in Medicine. 

To this day, it still marks the shortest amount of time a Nobel Prize was awarded following a medical breakthrough.