What is diabetes?
Diabetes mellitus is a disease that prevents your body from properly using the energy from the food you eat. Diabetes occurs when either:

  • The pancreas (an organ behind your stomach) produces little insulin or no insulin at all, or,
  • The pancreas makes insulin, but the insulin made does not work as it should. This condition is called insulin resistance.

What is insulin?
Insulin is a naturally-occurring hormone, produced by the beta cells of the pancreas, that helps the body use glucose for energy.

Understanding metabolism
To understand diabetes better, it helps to know more about how the body uses food for energy (a process called metabolism). Your body is made up of millions of cells. To make energy, the cells need food in a very simple form. When you eat or drink, much of your food is broken down into a simple sugar called glucose. Glucose (sugar) provides the energy your body needs for daily activities.

The blood and blood vessels are the highways that transport glucose from where it is either taken in (the stomach) or manufactured (in the liver) to the cells where it is used (muscles) or where it is stored (fat). Glucose cannot go into the cells by itself. The pancreas releases a substance called insulin into the blood which serves as the helper, or the "key" that lets glucose into the cells for use as energy. When glucose leaves the bloodstream and enters the cells, the blood glucose level is lowered.

Compare the human body to a car. To start a car, you must turn the key to move the gas to the engine. Without insulin, or the "key," glucose cannot get into the body's cells for use as energy. This causes glucose to rise. Too much glucose in the blood is called "high blood sugar" or diabetes.

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