The Facts
Diabetes mellitus is a condition where people don't produce enough insulin to meet their body's needs or their cells don't respond properly to insulin. Insulin is important because it moves glucose, a simple sugar, into the body's cells from the blood. It also has a number of other effects on metabolism.
The food people eat provides the body with glucose, which is used by the cells as a source of energy. If insulin isn't available or doesn't work correctly to move glucose from the blood into cells, glucose will stay in the blood. High blood glucose levels are toxic and cells that don't get glucose are lacking the fuel they need. These two problems cause the symptoms of diabetes.
There are two main kinds of diabetes: type 1 diabetes and type 2 diabetes. More than 90% of all people with diabetes have type 2. Overall, about 20 million people in North America have diabetes. Only about two-thirds of people with type 2 diabetes are aware of it and are receiving treatment because, for many people, early symptoms are not noticeable without testing.
Type 1 diabetes occurs when the pancreas cannot make insulin. Everyone with type 1 diabetes requires insulin injections. Type 1 diabetes occurs most commonly in people of northern European ancestry.
Type 2 diabetes occurs when the pancreas does not make enough insulin or the body does not use insulin properly. It usually occurs in adults, although in some cases children may be affected. People with type 2 diabetes usually have a family history of this condition and are most often overweight. People with type 2 diabetes may eventually need insulin injections. This condition occurs most commonly in people of American Indian descent, Hispanics, and North Americans of African descent.
Another less common form is gestational diabetes, a temporary condition that occurs during pregnancy. Gestational diabetes affects about 4% of pregnant women in the United States. The problem usually clears up after delivery, but women who have had gestational diabetes have a higher risk of developing type 2 diabetes later in life.