The human body is remarkably efficient when it comes to
managing resources—and one of the key players in this system is insulin.
This essential hormone plays a critical role in conserving energy by storing
nutrients when food is abundant. Excess carbohydrates are turned into glycogen
and stored in the liver and muscles, fats are packed away in adipose (fat)
tissue, and proteins are built from amino acids. All of this ensures that
the body has energy reserves when food isn’t readily available.
While our in-depth understanding of insulin is relatively
new, the health condition it’s closely linked to—diabetes—has been
documented since ancient times. Early references to symptoms of diabetes appear
in Egyptian and Greek texts, proving just how long this condition has
affected human health.
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| The islets of Langerhans (shown here in a high-power magnification), located in the pancreas, are responsible for the production of insulin. |
The Road to Discovery: A History of
Insulin
1869: The Islets of Langerhans
The modern story of insulin begins with Paul Langerhans,
a German medical student who, in 1869, identified a cluster of previously
unknown cells within the pancreas. These clusters would later be named the islets
of Langerhans—the very place where insulin is produced.
1889: Linking the Pancreas to Diabetes
In 1889, German scientists Joseph von Mering and Oskar
Minkowski took the next big step. Curious about the pancreas, they removed
the organ from a dog. The result? The dog quickly developed severe diabetic
symptoms, including high sugar levels in its urine—a key indicator of
diabetes. This experiment made it clear that the pancreas played a central role
in blood sugar regulation.
1921: The Breakthrough That Changed
Everything
Fast forward to 1921. In Canada, a determined surgeon named Frederick
Banting convinced John J.R. MacLeod, a professor at the University
of Toronto, to let him use his lab during summer break. With the help of Charles
Best, a young student, Banting repeated the pancreas removal experiment—but
this time with a twist.
They injected one of the diabetic dogs with an extract
from a healthy pancreas, and to their amazement, the dog’s diabetic
symptoms improved. They had just uncovered the therapeutic power of what we now
call insulin.
1922: First Human Treatment
In January 1922, the experiment reached a groundbreaking
milestone. Leonard Thompson, a 14-year-old boy with type 1 diabetes,
became the first human to receive insulin. The treatment worked—and it marked a
turning point in medical history.
Recognition, Controversy, and
Commercialization
In 1923, the discovery of insulin earned Banting and
MacLeod the Nobel Prize. However, the credit distribution sparked
controversy. Banting believed Charles Best deserved equal recognition
and shared his prize money with him. MacLeod did the same with James Collip,
the biochemist who helped purify the insulin extract.
That same year, pharmaceutical company Eli Lilly
began the mass production of insulin, making this life-saving hormone available
to diabetic patients around the world.
The Lifesaving Impact of Insulin
Before insulin, a diagnosis of type 1 diabetes was
essentially a death sentence—most patients, especially children, lived only a
few months after diagnosis. Today, thanks to insulin therapy, people with
well-managed diabetes can live just as long and as full lives as those without
the condition.
Key Takeaways for Readers
- Insulin
is a key hormone that stores excess energy and
helps maintain stable blood sugar levels.
- Diabetes
has been known for thousands of years, but its cause
remained a mystery until the late 19th and early 20th centuries.
- The
discovery of insulin in 1921 revolutionized diabetes treatment,
transforming a fatal disease into a manageable one.
- Early
pioneers like Banting, Best, and Collip played critical
roles in making insulin therapy a global medical breakthrough.
- Today’s
diabetes management tools—from insulin pumps
to glucose monitors—are built on this incredible scientific foundation.
✳️ Did you know? The first insulin
treatments were made using extracts from animal pancreases. Modern insulin,
however, is produced using advanced biotechnology, making it purer and more
effective than ever before.
💡 Worth thinking
about: What other modern diseases could be drastically changed by a
breakthrough as monumental as insulin?
