In Type 1, or insulin dependent diabetes, the cells in the pancreas that normally produce insulin have been destroyed. Type I diabetes is also called juvenile onset diabetes. This occurs in children or young adults. But it is not unusual in older people as well. It is still not known what causes the destruction of the insulin-producing cells in the pancreas, or why it happens in some people and not in others.
Hereditary factors appear to play a role, but the disorder is practically never directly inherited.
Diabetics, or people with diabetes in their family, are therefore not advised against having children. The remedy is to inject insulin under the skin so that it can be absorbed into the blood. It has not yet been possible to produce a form of insulin that can be taken by mouth, since insulin is broken down to an inactive form in the stomach. In type II diabetes there may be three areas of trouble. In Type II diabetes, the cells in the pancreas still produce insulin, but they may have lost their ability to replenish the insulin supply quickly when needed.