Diabetes mellitus type 2 and primarily a lack of insulin secretion. Other potentially important mechanisms associated with type 2 diabetes and insulin resistance include: increased breakdown of lipids within fat cells, resistance to and lack of incretin, high glucagon levels in the blood, increased retention of salt and water by the kidneys, and inappropriate regulation of metabolism by the central nervous system. However, not all people with insulin resistance develop diabetes, since an impairment of insulin secretion by pancreatic beta cells is also required. The World Health Organization definition of diabetes (both type 1 and type 2) is for a single raised glucose reading
Diabetes mellitus type 1 diabetes is diagnosed first. Some people with type 1 diabetes experience dramatic and recurrent swings in glucose levels, often occurring for no apparent reason; this is called "unstable diabetes","labile diabetes" or "brittle diabetes". The results of such swings can be irregular and unpredictable hyperglycemias, sometimes involving ketoacidosis, and sometimes serious hypoglycemias. Brittle diabetes occurs no more frequently than in 1% to 2% of diabetics. Type 1 diabetes is associated with alopecia areata (AA). Type 1 diabetes is also more common in the family members of people with AA. The cause of type 1 diabetes is unknown. A number of explanatory