Diabetes was formerly a death sentence, but the discovery of insulin changed that
Today, diabetics learn how to live with the disease rather than how to survive.

I live with diabetes and had a chocolate-dip donut from Tim Hortons yesterday. It tasted amazing. And I am completely fine. You might’ve seen diabetes as the punchline caption hanging below a chocolate cake Instagram post: “diabetes never tasted so good.” But no, sweet snacks don’t taste like diabetes. Diabetes sucks. 

In the weeks leading up to my own diagnosis 12 years ago, I wet my bed, soiled my pants in class, kept unusually chugging down gallons of water, and suffered from extreme fatigue. This continued for about two weeks until my parents dragged me to the hospital, where I fainted. 

Today, I expect to live a full life. A hundred years ago, even after a diagnosis, no effective treatment existed. Hospital wards were filled with bedridden diabetic skeletons draped in skin. Occasionally, some diabetics regained semi-consciousness before relapsing into a coma. 

Diabetes was a death sentence—that is until Dr. Fredrick Banting discovered insulin in 1921. 

The discovery of diabetes

The Greek physician Aretaeus of Cappadocia first coined the term “diabetes” 1900 years ago. Diabetes translates to “siphon.” As Aretaeus stated: “No essential part of the drink is absorbed by the body while great masses of the flesh are limbs into urine.” For Aretaeus, he only saw his patients eating whole meals and coming back each consecutive day looking more and more like the skeletal undead.

Diabetes comes in a few different subtypes. The one Aretaeus described was eventually named diabetes mellitus. The word mellitus—Latin for honey—describes the sweet taste of urine from diabetic individuals. Urine was a defining diagnostic. Under normal circumstances, one does not expect urine to be anything remotely close to honey. Given that the diabetic body didn’t absorb any nutrients, it made sense that any sugars consumed would simply waste away in the disposed urine. Unfortunately for physicians of the past, the only way to accurately diagnose someone with diabetes for hundreds of years was by taste. Hence diabetes mellitus—sweet siphon. 

What diabetes does

In a non-diabetic body the digestive system takes full control of food absorption and digestion. The stomach mashes food to a pulp, the small intestine absorbs it, and the liver processes nutrients and ejects them into the bloodstream.

Amongst these nutrients are carbohydrates, which break down into glucose. Cells take in glucose and use it in a process called cellular respiration. This process uses glucose and oxygen to make an energy molecule called Adenosine Triphosphate (ATP). Without ATP, the body collapses. 

Cells must take in glucose for cellular respiration to occur. However, glucose can only enter cells through specific glucose transporters, akin to cell gates. These “gates” need a corresponding “key” to open.

In 1889, researchers at the University of Strasbourg in France found that removing a dog’s pancreas induced severe diabetes. They concluded that the pancreas must hold the key to treating diabetes. Scientists dubbed this hypothesized key to what we know as insulin. The pancreas produces insulin through a series of island-shaped cells called the Islets of Langerhans.

According to the American Diabetes Association, the immune system in a diabetic body goes rogue. Normally, it detects and destroys invaders it deems foreign and harmful. Through an as-of-yet unknown mechanism, the immune system mistakenly identifies the Islets of Langerhans as foreign and harmful and therefore destroys them in an autoimmune attack. 

Without the islets, the pancreas cannot produce insulin. This causes two main problems: the first is hyperglycaemia, which is a surplus concentration of blood glucose that eventually clogs the bloodstream; the second is a severe lack of glucose inside the cells.

How the body reacts

To revert hyperglycaemia (or high blood glucose), the body attempts to autocorrect by filtering the glucose out of the kidneys into urine, known as glycosuria. This causes frequent urination, which consequently leads to increased thirst, dehydration, and damage to the kidneys.

During this time, glucose remains inaccessible for cellular respiration, which leads to a lack of energy molecules (or ATP), which then causes the body to collapse. Consequently, the body self-cannibalizes any accessible fats, muscles, proteins, and other “non-essential” body resources for energy. This yields far less energy and leads to toxic ketones. In large concentrations, ketones acidify the blood and pose a life-threatening condition known as diabetic ketoacidosis (DKA). 

Was I suffering from diabetic ketoacidosis before my own diagnosis? If I wasn’t already, I most likely would have in a few more days. Today, DKA mandates a trip to the emergency room—people usually survive. A hundred years ago, diabetic ketoacidosis was always fatal. In fact, it compounded the problem introduced with severe hyperglycaemia. Ketones made the blood acidic, glucose clogged the blood vessels like plaque, eating food only exacerbated the problem.

Starving to survive

In 1919, the best treatment for diabetes was a starvation diet published by Dr. Fredrick Allen of the Rockefeller Foundation in New York. Patients started with a strict week-long fasting period. During this time, the lack of new glucose allowed the kidneys to slowly filter out high blood sugar levels through the urine. Doctors then slowly reintroduced macronutrients like fats, proteins, and carbohydrates into the body. Eventually, they fed patients until they detected glucose in the urine again. In his findings, Allen recommended a fat-heavy, low-carb diet. These diets helped marginally extend diabetic lifespans. 

The good news

In 1921, Dr. Fredrick Banting and his colleagues at the University of Toronto isolated pancreatic insulin. A year later, Banting injected insulin for the first time into Leonard Thompson, a dying 14-year-old boy who had been suffering from type 1 diabetes. After the shot, his blood sugar levels stabilized. He lived another 13 years until he died from pneumonia.

After the initial discovery, Banting sold the subsequent patents for insulin to the University of Toronto for a symbolic $1.00 price. As he aptly put it, “insulin belongs to the world, not me.”

Not withholding the patent allowed rapid advancement in diabetic research over the century. Today, the insulin pump, a device that mimics the human pancreas and delivers insulin into the body, replace injections and allow better control over diabetes. These pumps are advancing closer and closer to a truly artificial pancreas. 

Over the years, with a strong support system full of helpful family, teachers, and friends—one that empowers instead of mocks–I have grown out of any embarrassment I feel toward my disease.

I ate that donut yesterday just like anyone else. I had to manually give myself insulin, sure, but while diabetes still exists, it is no longer a crippling disease. And maybe in a few more years, someone may stumble upon the cure. A hundred years ago, diabetes was no longer a death sentence. Perhaps in another hundred years, diabetes may no longer be a sentence at all. That is the dream.