Type I Diabetes

By: CPMC Genetic Counseling Staff
Reviewed by: Dr. Ghada Haddad, MD, Cooper University Hospital

Type 1 diabetes is an autoimmune disease where the body's immune system attacks the insulin producing cells in the pancreas. Insulin is needed to convert the sugar in food to energy. Type 1 diabetes – also known as juvenile diabetes or insulin dependent diabetes – occurs when the body does not make insulin. Type 1 diabetes is most often diagnosed in children and young adults, but can occur at any age. Approximately 37% of people with type 1 diabetes are diagnosed in adulthood.

Type 1 Diabetes vs. Type 2 Diabetes
Type 1 diabetes is less common than type 2 diabetes. About 7% of people diagnosed with diabetes in adulthood have type 1 diabetes; the remaining 93% have type 2 diabetes. For example: if 100 adults are diagnosed with diabetes, approximately 7 of them would be diagnosed with type 1 diabetes. Type 1 diabetes is always treated with insulin. Type 2 diabetes can sometimes be controlled with diet or oral medications, but insulin also may be required in the treatment of type 2 diabetes.

The Role of Insulin in Diabetes
Insulin is a hormone made by special cells in the pancreas called beta cells. Every time you eat your body breaks down the carbohydrates (starches) in your food into sugar (called glucose). The rise in the level of sugar in your blood signals the beta cells of your pancreas to immediately release insulin. The insulin then transports the glucose (sugar) to the organs to be used as energy right away or to be stored in the liver and muscles for future use. If there is not enough insulin in the body, then glucose (sugar) will build up in the blood rather than being delivered to the organs. It is possible to track the amount of sugar that is building up in the blood by looking at your blood sugar level. In addition to high blood sugar being a sign of diabetes, a high blood sugar level can be a sign that the organs are not getting enough sugar which can lead to organ damage. The organs most at risk are the eyes, kidneys, nerves, muscles and heart.

How Common is Adult-onset Type 1 Diabetes?
In the United States, about 3 in every 1000 adults have adult onset type 1 diabetes. Caucasians are more likely to be affected than any other ethnicity. Click here to view the data. 

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Learn more about Type 1 diabetes, from symptoms to understanding your risk, through the links below.

Symptoms, Diagnosis, Treatment

Learn more about Type I Diabetes [ Learn More › ]

Risk Factors

Both genetic and non-genetic factors play a role in Type I Diabetes [ Learn More › ]


Reduce Your Risk

Risk-reducing behaviors for Type I Diabetes [ Learn More › ]

The CPMC Study

Learn how the CPMC Study identifies your risk for Type I Diabetes [ Learn More › ]


Educational Sessions

An educational video series on Type 1 Diabetes Learn More› ]