Type I diabetes is a disease in which the body is unable to properly regulate blood sugar or glucose levels in the blood, due to little or no insulin. Insulin is a hormone produced by the beta cells of the pancreas and controls the uptake of glucose into cells from the bloodstream for energy. The exact cause of type 1 diabetes is unknown, but environmental and genetic factors play a role.
Autoimmune Response
Normally, the immune system attacks only foreign bacteria and viruses in the body, but in autoimmune diseases, the body's own cells are targeted and destroyed by the immune system. In type 1 diabetes, the beta cells are destroyed, eventually resulting in little or no insulin production. The reason the immune system attacks the beta cells is unclear, but it is believed that both genetic and environmental factors are at work, according to the University of Maryland Medical Center.
Genetic Factors
Genes have been identified that predispose, as well as protect, individuals from type 1 diabetes. Many genetic locations and regions have been identified with the most important being genes that encode proteins important for immune system function. Despite specific genes being identified as a possible cause, type 1 diabetes has not been shown to run in families, suggesting more is at play than just genes, according to the University of Maryland Medical Center.
Environmental
In individuals with a genetic predisposition for type 1 diabetes, several agents have been studied as a possible triggers for the development of type 1 diabetes. These agents include viruses, infant diet and toxins, according to a paper in the July 2001 issue of "The Lancet." More specifically, researchers are looking at viruses that attack the intestinal tract, breast feeding versus cow's milk, and derivatives of a carcinogenic compound called N-nitroso. However, no clear link has been established providing further evidence that multiple, interacting factors cause type 1 diabetes.
Disorders and Complications
Various genetic and hormonal disorders, as well as complications from diseases or surgeries can increase the risk of developing type 1 diabetes. Rare genetic disorders include Klinefelter syndrome, Huntington's chorea, and Wolfram syndrome. Hormonal disorders, such as acromegaly, Cushing's syndrome, and pheochromocytoma, increase the risk due to changes in the body's hormone levels. Damage to the pancreas may also lead to type 1 diabetes, such as that caused by pancreatitis or from pancreatic surgery, according to the University of Maryland Medical Center.
