The term diabetes mellitus describes a metabolic disorder of multiple etiology characterized by chronic hyperglycaemia with disturbances of carbohydrate, protein and fat metabolism resulting from defects in insulin secretion, or both. The effect of diabetes mellitus include long-term damage and failure of multiple organs. Diabetes mellitus may present with characteristic symptoms such as thirst, blurring of vision, polyuria and weight loss. In its most severe forms, ketoacidosis or a non-ketotic hyperosmolar may develop and lead to stupor, coma and, in absence of effective treatment, could result in death. Often the symptoms are mild by low blood sugar levels cause pathological and functional changes. The long-term impact of diabetics, as well as the development of the progress of specific complications of retinal, nephropathy that can lead to renal failure, and/or neuropathy with risk of foot ulcers, amputation, and features of central nervous system dysfunction, including sexual dysfunction. People with diabetes are at increased risk of cardiovascular and stroke disease.The processes that cause many disease and involved in the development of diabetes. These include a process that destroys the beta cells of the pancreas with insulin deficiency occurred and others that are in opposition to the action of insulin. Disorders of carbohydrate, fat and protein metabolism caused by a lack of insulin action in target tissues caused by insensitivity or lack of insulin.