The main cause of diabetes is that the insulin produced by the pancreas does not work properly, so the body has abnormally high blood sugar levels. There are two important reasons for this: either there is no insulin present in the body, type 1 diabetes, or there is insulin but it is unable to act, type 2 diabetes. Type 1 diabetes mellitus is also called insulin. dependent because the secretion of the hormone insulin by the pancreas is reduced to minor levels due to the destruction of pancreatic beta cells by the body's immune system. Therefore, type 1 diabetes is an autoimmune disease because the body damages the pancreas with antibodies, so the beta cells cannot produce insulin so the blood can absorb glucose. The fact that the body's cells cannot absorb glucose means that it builds up in the blood and hyperglycemia occurs. This abnormally high blood glucose level can damage the nervous system, the tiny blood vessels in the kidneys, heart and eyes. Type 1 diabetes is fatal when left untreated because it causes heart disease, kidney disease, nerve damage, stroke and