Also known as: juvenile diabetes, insulin-dependent diabetes mellitus (IDDM), childhood diabetes, and ketosis prone diabetes (Note: some of these terms are now outdated).

Type 1 diabetes accounts for between 5 and 10% of all diagnosed diabetes in the United States. Although type 1 diabetes develops most often in children and young adults (one in every 400-500 children has type 1 diabetes), the disease can be diagnosed at any age throughout the lifespan, and is equally distributed among males and females. Unlike type 2 diabetes, type 1 diabetes is more common in Caucasians than in those of Latino, African-American, or other non-Caucasian backgrounds.

Type 1 diabetes is an autoimmune disease that occurs when the insulin-producing beta cells within the pancreas are gradually destroyed and eventually fail to produce insulin. Insulin is a hormone that helps the body's cells use glucose for energy. Blood glucose (or blood sugar) is manufactured from the food we eat (primarily carbohydrates) and by the liver. If glucose can't be absorbed by the cells, it builds up in the bloodstream instead, and high blood sugar is the result. Over time, the high blood glucose levels of uncontrolled diabetes can be toxic to virtually every system of the body.

Because type 1 diabetes is frequently diagnosed in childhood, it is sometimes referred to as juvenile diabetes. However, it can develop at any age throughout adulthood. Early diagnosis is important to prevent some of the more serious complications of diabetes, which include heart disease, blindness, high blood pressure, nerve damage, and kidney failure. In addition to following an exercise and healthy eating plan, individuals with type 1 diabetes require insulin injections.

The causes of type 1 diabetes are complex and still not completely understood. People with type 1 diabetes are thought to have an inherited, or genetic, predisposition to the disease. Researchers believe that this genetic predisposition may remain dormant until it is activated by an environmental trigger such as a virus or a chemical. This starts an attack on the immune system that results in the eventual destruction of the beta cells of the pancreas.

There are several subtypes of type 1 diabetes, including type 1A diabetes, idiopathic diabetes (type 1B), and latent autoimmune diabetes of adulthood (LADA). The basic treatment (i.e., insulin injections) is the same for all.