Type I, Type II and gestational diabetes.
All humans require the use of glucose, because of the simple reason that it powers the entire body.
People who do not have diabetes rely on the insulin created by the body. Insulin is a hormone that is used for the purpose of moving glucose from the blood into the body's cells. But people who have diabetes either don't produce insulin or cannot use the insulin they produce. Glucose gathers in the blood, this alone is called hyperglycemia, which is the scientific term for too much glucose in blood. The symptoms of hyperglycemia include incredible thirst, the need to urinate frequently, unclear or blurry vision, nausea and fatigue, and much more.