Type 1 diabetes develops when the immune system turns on itself and destroys cells in the pancreas that are responsible for producing insulin. Scattered throughout the pancreas are beta cells called islets of Langerhans that produce the insulin your body needs to process blood sugar and survive. When roughly 90% of these beta cells have been destroyed, classic symptoms of type 1 diabetes become evident. This reduction in insulin causes blood sugar to accumulate in the blood and, if untreated, can be life-threatening. Why the beta cells suddenly stop producing insulin is still unclear to researchers, but the three most likely culprits appear to be:
A family history of diabetes is present for some people. If a first-degree family member, such as a parent or sibling, has diabetes, then you have a slightly greater risk of having diabetes. Although no specific gene that causes diabetes has been found, researchers have identified a number of genes that seem to play a part in the development of type 1 diabetes. The genes in question have an important role in creating proteins that affect the function of the immune system. As these genes are studied further it may shed light on what causes the autoimmune response that stops the production of insulin.
Some evidence exists that certain viruses may trigger a response in the immune system that is similar to a search and destroy mission; shutting down insulin production in the pancreas. There are several viruses under study, but the one that has elicited the most interest is called coxsackievirus, which is fairly common in children. The vast majority of children fully recover within a few days no lingering effects. But a small percentage of cases lead to more serious infections. Some researchers are studying whether the coxsackievirus acts as a trigger for the autoimmune response to destroy beta cells.
A number of researchers are turning their attention to the role of environmental influences in the development of type 1 diabetes. When combined with genetic factors, exposure to certain environmental influences such as climate and infant diet may raise the risk of type 1 diabetes. But no definitive link between environment and cause of type 1 has been established.
Though the exact cause(s) are not yet known, we know for certain that diabetes is not caused by eating foods with high sugar content.
Type 1 Diabetes. University of Maryland Medical Center. Accessed: September 18, 2008. http://www.umm.edu/patiented/articles/what_causes_type_1_diabetes_000009_2.htm
Causes of Type 1 Diabetes. Intelihealth. Accessed: September 18, 2008. http://www.intelihealth.com/IH/ihtIH/WSIHW000/35132/35250/363533.html?d=dmtContent
Coxsackieviruses. Nemours Foundation. Accessed: September 18, 2008. http://kidshealth.org/parent/infections/bacterial_viral/coxsackie.html