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Understanding Diabetes -- the Basics

Diabetes, the most common disorder of the endocrine (hormone) system, occurs when blood sugar levels in the body consistently stay above normal. It affects more than 25 million people in the U.S. alone.

Diabetes is a disease brought on by either the body's inability to make insulin (type 1 diabetes) or by the body not responding to the effects of insulin (type 2 diabetes). It can also appear during pregnancy. Insulin is one of the main hormones that regulates blood sugar levels and allows the body to use sugar (called glucose) for energy. Talk with your doctor about the different types of diabetes and your risk for this disease.

Understanding Diabetes

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Diagnosis and Treatment



In the U.S., 79 million people over age 20 have blood sugar levels that are higher than normal, but not high enough to be classified as diabetes. This is known as pre-diabetes, or impaired glucose tolerance. While people with pre-diabetes usually have no symptoms, it’s almost always present before a person develops type 2 diabetes. However, complications normally associated with diabetes, such as heart disease, can begin to develop even when a person has only pre-diabetes.

Once type 2 diabetes develops, symptoms include unusual thirst, a frequent need to urinate, blurred vision, or extreme fatigue -- or there may be no symptoms. Talk to your doctor to see if you need to be tested for pre-diabetes. By identifying the signs of pre-diabetes before diabetes occurs, you may be able to prevent type 2 diabetes and lower your risk of complications associated with this condition, such as heart disease.

Type 1 Diabetes

Type 1 diabetes occurs because the insulin-producing cells of the pancreas (called beta cells) are destroyed by the immune system. People with type 1 diabetes produce no insulin and must use insulin injections to control their blood sugar.

Type 1 diabetes most commonly starts in people under the age of 20, but may occur at any age.

For more detail, see WebMD's article Type 1 Diabetes.

Type 2 Diabetes

With type 2 diabetes, the body continues to produce insulin, although insulin production by the body may significantly decrease over time. The pancreas produces either not enough insulin, or the body is unable to recognize insulin and use it properly. When there isn't enough insulin or the insulin is not used as it should be, glucose can't get into the body's cells to be used as energy.This glucose then builds up in the blood.

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