Type 1 Diabetes

If your doctor recently diagnosed you with diabetes, you're one of nearly 16 million people in the United States -- nearly one in 17 people -- who have diabetes. Approximately 2,200 new cases are diagnosed each day.

Type 1 Diabetes
People with type 1 diabetes (also called insulin-dependent diabetes mellitus or IDDM) don't produce insulin and need regular shots of it to keep their blood glucose levels normal. Type 1 diabetes was once called juvenile-onset diabetes, but that name has been dropped because type 1 diabetes also strikes young and older adults alike. Type 1 diabetes accounts for about 5% to 10% of those who have the disease.

Risk Factors

• A family history of the disease increases risk.
• Diabetes happens in people of every race, but it's most common among whites.
• Half of those diagnosed with type 1 are under 20. Being age 20 or younger increases your risk.

What Causes it?
Most children of parents with diabetes do not develop the disease. However, scientists have long suspected that heredity plays a role because type 1 diabetes tends to run in families. Researchers have identified several genes that appear to increase risk of type 1 diabetes. But they haven't yet found a single gene that causes the disease.

Type 1 diabetes has many hallmarks of an auto-immune condition. In auto-immune diseases, the immune system, which protects you from disease by killing invading germs, mistakes the body's own cells for germs and destroys them. In the case of type 1 diabetes, the immune system kills the cells in the pancreas that produce insulin (beta cells).

Type 1 diabetes often strikes shortly after a viral infection, and doctors sometimes notice a sharp jump in type 1 diabetes diagnoses after viral epidemics. Which viruses? Candidates include those that cause mumps, German measles, and a close relative of the virus that causes polio.

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