Type 1 diabetes usually develops when the immune system destroys the beta cells in the pancreas, which produce insulin. This is called an autoimmune response.
This means that the body’s own immune system gets confused, and mistakes beta cells for foreign bodies, like bacteria, and it attacks and destroys them. When over 90% of beta cells are destroyed, a process which takes months or even years to develop, the body fails to produce enough insulin.
At this point the blood sugar levels start to rise and the symptoms common to diabetes like thirst and frequent urination begin to appear.
Type 1 Diabetes Causes
Type 1 diabetes can develop in people with or without a family history of type 1 diabetes.
In either case, people who develop diabetes have one or more genes that make them susceptible to the disease. It is thought that environmental factors, such as exposure to certain viruses, or certain foods early in life, might trigger the immune response. First degree relatives of a person with type 1 diabetes have a 5-6% chance of developing diabetes vs. 0.4 % in someone with no family history.
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