By now, you probably know a lot about diabetes. You know you have to take shots, test your blood, and watch what you eat. But did you ever wonder what causes diabetes? Or how long it has been around?

What Exactly Is Diabetes?
The foods we eat are broken down, absorbed into the bloodstream, and then used by the body for energy. Insulin is the chemical the body makes to help convert sugar in the blood into energy. Insulin is made in the pancreas, a long, skinny gland that sits behind your stomach.

You probably have a type of diabetes called Type 1 or insulin-dependent diabetes, which usually develops in childhood. In people with this type of diabetes, the body no longer makes enough insulin to do a good job of breaking down sugar in the blood. That's why all people with Type 1 diabetes have to take at least one shot of insulin every day just to stay alive.

Scientists aren't sure exactly why Type 1 diabetes happens, but they know it has something to do with the immune system, the mechanism in the body that fights off colds and infections. For some reason, in certain people, the immune system screws up and begins attacking and destroying the body's own cells: those of the pancreas that make insulin.

When enough of these cells are destroyed, and the pancreas can no longer make enough insulin to break down the sugar in the blood, the symptoms of diabetes begin to appear. See if you remember having any of them:

• Frequent urination, because the body is trying to get rid of excess sugar.

• Strong thirst, because the body wants to replace all the fluid lost through the urine.

• Strong hunger and weight loss, since without insulin to help use the food you eat, the body begins to starve.

Strange Stories
Diabetes has been around a very long time. There was a prescription for frequent urination, its most common symptom, on an Egyptian papyrus dating back to 1500 B.C.

Much later, in 100 A.D., the Greek physician Aretaeus of Cappadocia first named the condition "diabetes," which is Greek for "siphon," since people with diabetes urinated so often.

In 1889, two medical researchers in Europe, J. von Mering and O. Minowski, removed the pancreas of a dog to see what would happen. The dog began to urinate a lot, and the researchers noticed there were flies swarming around the pools of urine. When they tested the urine and discovered that it contained sugar, they realized the dog had developed diabetes. Now they knew that diabetes was a disease of the pancreas.

Until this century, the only way doctors had to treat diabetes was through diet. Aretaeus of Cappadocia prescribed a diet of milk, gruel, cereal, and wine. Other doctors throughout history tried a strict meat diet, and still others tried a diet high in fat. These diets didn't help, of course. People with Type 1 diabetes usually only lived a few months after they developed it.

Real Progress
Then, in 1921, in Toronto, Ontario, Canada, something happened that would change the lives of people with diabetes forever. Dr. Frederick G. Banting and a medical student, Charles H. Best, took fluid from animal pancreases, purified it, and injected it into Leonard Thompson, an 11-year-old boy suffering from severe diabetes. Leonard was barely alive and weighed only 75 pounds.

But after injections of the fluid, his blood sugar levels went down, he was able to eat a more normal diet, he gained weight, and he lived to be an adult. The magic ingredient in that fluid was—you guessed it!—insulin.

Unfortunately, as people with diabetes started living longer, doctors noticed that they tended to develop diseases of the eyes, kidneys, nerves, and blood vessels. Doctors began to suspect that these problems might be due to high levels of sugar in the blood, so better ways of testing the sugar levels were developed.

In the early 1980s, more and more people started testing the amount of sugar in their own blood, known as the blood glucose level. And now doctors say you should check several times every day.

It's not much fun, but testing blood sugar helps you make changes in your insulin dose, the amount of food you eat, and the exercise you get in order to keep the blood sugar level as close to normal as possible.

In 1993, an important scientific study called the Diabetes Control and Complications Trial, or "DCCT," proved beyond a shadow of a doubt how important it is to control your blood sugar levels. This way, people with diabetes can decrease their chances of developing eye, kidney, and nerve problems.

The Future
Scientists are now testing whether giving insulin injections or a pill might keep people from getting diabetes, at least for a little while. Scientists are convinced that some day in the future a treatment can be used to vaccinate all children against diabetes.

Since 1971, scientists have been trying to create an artificial pancreas to try to cure diabetes in people who already have it. With an artificial pancreas, a person with diabetes could have controlled blood sugars without having to inject insulin. The artificial pancreas is still years away, but scientists are confident that it will happen.