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Type 2 Diabetes

Type 2 diabetes is a lifelong disease that affects the way your body uses food for energy. The disease develops when the cells of the body become resistant to insulin and/or when the pancreas cannot make enough insulin, which causes high blood sugar.

Insulin is a hormone that helps your body's cells get needed energy from sugar. When insulin is not able to do its job, too much sugar builds up in your blood. Over time, this extra sugar in your blood can lead to problems with your eyes, heart, blood vessels, nerves, and kidneys.

Common symptoms of diabetes are increased thirst, frequent urination, increased hunger, unusual weight loss, and extreme fatigue. But in type 2 diabetes, blood sugar levels rise so slowly that a person usually does not have symptoms and may have the disease for many years before being diagnosed with it.

Type 2 is the most common type of diabetes. People who develop type 2 diabetes often are overweight and not physically active. It is most common in people who are older than 40 but is becoming more common in children. Type 2 diabetes used to be called adult-onset diabetes, or non-insulin-dependent diabetes mellitus (NIDDM).

Type 2 diabetes can be prevented or at least delayed if a person maintains a healthy body weight and exercises regularly. Treatment focuses on keeping blood sugar, cholesterol, and blood pressure at safe levels. A balanced diet and regular exercise are effective for many people, but some may need one or more medicines, including insulin, to help control blood sugar levels.

ByHealthwise Staff
Primary Medical ReviewerE. Gregory Thompson, MD - Internal Medicine
Specialist Medical ReviewerJennifer Hone, MD - Endocrinology, Diabetes and Metabolism
Last RevisedJune 29, 2011

eMedicineHealth Medical Reference from Healthwise


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