Diabetes mellitus, often simply referred to as diabetes, is a group of metabolic diseases in which a person has high levels of blood sugar, either because the body does not produce enough insulin or because cells do not respond to the insulin that is produced.
This high blood sugar produces the classic symptoms of polyuria (frequent urination), polydipsia (increased thirst) and polyphagia (increased hunger). Diabetes is the fifth most common disease in the world after malaria, tuberculosis, common cold and cancer and is one of the biggest causes of premature illness and death worldwide. It was estimated that approximately four million people died of diabetes in 2010. This is largely due to a 29% increase in the number of deaths due to diabetes in the North America and Caribbean Region.