What Is Type 2 Diabetes?

What does "type 2 diabetes" mean?

Type 2 diabetes is one of two main kinds of diabetes and is the most common form of the disease. The other kind is known as type 1 diabetes.

Type 1 diabetes. People with type 1 diabetes have a specific genetic makeup that causes their bodies to attack some of their own cells -- insulin-producing cells, in fact -- which makes it an autoimmune disease. Those who suffer from type 1 diabetes usually develop severe symptoms over a short time and require regular insulin injections or infusions through a pump. This disorder is generally diagnosed in childhood, adolescence, or young adulthood, which is why it was formerly known as juvenile-onset diabetes or insulin-dependent diabetes mellitus.

Type 2 diabetes. Type 2 diabetes strikes when a person's body loses the ability to produce or properly use the hormone that regulates blood sugar. Type 2 diabetes accounts for nearly 95 percent of all diabetes cases. It's often, but not always, diagnosed in people over age 40, hence its former moniker, adult-onset diabetes. (It also used to be known as non-insulin-dependent diabetes mellitus, but this term is considered outdated as well.)

What makes type 2 diabetes so dangerous?

Type 2 diabetes strikes when a person's body loses the ability to produce or properly use the hormone insulin. The result is too much sugar in the blood.

Insulin is like a key that unlocks the door to cells, so that glucose -- a simple sugar and the primary energy source that fuels the body -- can enter. Without insulin, cells starve and blood glucose stays in the bloodstream, exceeding the normal levels of between 80 and 110 milligrams per deciliter of blood (mg/dL).

In the short term, blood glucose levels that are either very high or very low can lead to serious medical problems, even emergencies. The person in your care could become unconscious and go into a diabetic coma, called diabetic ketoacidosis, if his blood sugar numbers skyrocket. High blood sugar is known as hyperglycemia. He can also lose consciousness if his numbers plummet to dangerously low levels, a condition called hypoglycemia.

In the long term, too much sugar in a person's blood can damage nearly every organ in the body. People with diabetes also appear to be at increased risk for a host of other ailments, including Alzheimer's disease, dementia, heart disease, and stroke.

Sarah Henry

Sarah Henry has covered health stories for most of her more than two decades as a writer, from her ten-year stint at the award-winning Center for Investigative Reporting to her staff writer position with Hippocrates magazine to her most recent Web work for online sites, including WebMD, Babycenter. See full bio