Type 1 diabetes develops when your pancreas makes little if any insulin. Without insulin circulating in your bloodstream, sugar can't get into your cells, so it remains in your blood.

Type 1 diabetes used to be referred to as insulin-dependent diabetes or juvenile diabetes. That's because the disease most often develops when you're a child or a teen, and you need to administer insulin medication daily to make up for the insulin your body doesn't produce. The names insulin-dependent diabetes and juve­nile diabetes are used less often today because they're not entirely accurate. Though less common, adults also can develop type 1 diabetes - not just juveniles. In addition, use of insulin isn't limited only to people with type 1 disease. People with other forms of diabetes also may need insulin.

Type 1 diabetes is an autoimmune disease, meaning that your own immune system is the culprit. Similar to how it attacks invad­ing viruses or bacteria, your body's infection-fighting system attacks your pancreas, zeroing in on your beta cells, which produce insulin. Researchers aren't certain what causes your immune sys­tem to fight your own body, but they believe genetic factors, expo­sure to certain viruses and diet may be involved. The attack can dramatically reduce - even entirely wipe out - the insulin-mak­ing capacity of your pancreas.

Between 5 percent to 10 percent of people with diabetes have type 1, with the disease occurring equally among males and females. Type 1 diabetes can smolder and remain undetected for several years. More often, though, symptoms come on quickly, commonly following an illness.