[Skip to Content]
University of Illinois Extension

What is Diabetes?

Diabetes is a disease in which the glucose in the blood is higher than normal. High blood glucose is called hyperglycemia.

Glucose is a type of sugar that comes from foods containing carbohydrates and is found in everyone’s blood. Glucose is transported through the blood to all tissues and organs to be used for energy.

definition of diabetes

Blood glucose should not be too low (hypoglycemia) or too high (hyperglycemia). The body usually keeps blood glucose within a certain range. When blood glucose begins to rise above normal, it either enters cells to be used for energy, or it is stored. If it is stored for future use, it will be converted to glycogen or fat. Glycogen is a “quick fuel”that is found in muscle and the liver.

When blood glucose needs to enter a cell to provide it with energy, it often needs the help The body is normally able to control blood glucose levels using of a hormone called insulin. Insulin is released by the pancreas in response to increased levels of glucose in the blood. Insulin, blood glucose and the cell’s receptor all work together to move the glucose into the cell.

With diabetes, however, the body has trouble making or using insulin. For this reason, blood glucose levels rise and hyperglycemia occurs.

To imagine how glucose, insulin, and cell receptors work, think of your car. To park in your garage, you need a garage door and a garage door opener. Glucose is like your car, the cell receptor is like the garage door, and the insulin is like the opener.

If your body does not make enough insulin or if it does not work properly, glucose cannot get into your cells. Instead, glucose stays in your blood causing high blood glucose, or hyperglycemia. People with hyperglycemia have diabetes.


This site was last updated June, 2014.
This is a source of information only, and is not medical advice.