Diabetes, a term commonly used for diabetes mellitus, is a chronic disease caused by a deficiency in insulin secretion, as in type 1 diabetes, or a resistance of cells to this hormone, as in type 2 diabetes. These mechanisms generate an abnormal accumulation of glucose in tissues and blood. Insulin is produced by the pancreas and plays a key role in reducing blood sugar and promoting the use of sugar by the cells. Medical care is based on a strict dietary education, medication, and close monitoring. Treatments against diabetes aim to lower blood sugar, because chronic hyperglycemia is responsible for long-term complications. It may include medicines taken by mouth or insulin injections.