2 What is diabetes?
Diabetes mellitus is a condition in which the glucose level in the blood is higher than it should be. The word ‘diabetes’ comes from the Greek word for ‘siphon’. A siphon is a way of removing liquid, and diabetes is used to describe disorders that remove liquid from the body, resulting in excessive thirst and the production of large amounts of urine. There are two forms of diabetes, diabetes mellitus and diabetes insipidus, of which diabetes mellitus is the more common. The word ‘mellitus’ comes from the Latin word for ‘honeyed’. Diabetes mellitus, therefore, describes a condition that produces ‘sweet urine’. This production of sweet urine occurs as a result of a high glucose level in the blood. Some of the glucose enters the urine, making it taste sweet. Glucose is a type of simple sugar that is a building block of more complex sugars called carbohydrates. Diabetes mellitus has been known for thousands of years, having been described by the Ancient Egyptians and the Romans. Over the years more and more has been discovered about diabetes mellitus, and the way it is diagnosed has been refined.
Diabetes insipidus is a different condition that will not be discussed in any detail. It is a very rare condition caused by the lack of a hormone needed to concentrate urine. This hormone is produced in the brain. Diabetes insipidus shares the name diabetes as it also results in the production of large quantities of urine, but has nothing to do with how the body manages glucose.
This course is aimed at developing an understanding of diabetes mellitus. Throughout the course the term diabetes will be used to describe diabetes mellitus, unless otherwise indicated.