Diabetes is a chronic condition that develops when the body no longer produces enough insulin or the insulin it makes does not work effectively. Insulin is a hormone made by an organ called the pancreas, located near the stomach. 

One of the ways the body gets energy is from the food we eat. Digestion allows the body to break carbohydrates down into glucose. Insulin allows the glucose to move into the cell so it can be used for energy. 

A lack of insulin prevents glucose from moving out of the blood and into the cells. This causes glucose to build up in the blood, resulting in hyperglycemia, also called high blood glucose.  Hyperglycemia is a main symptom of diabetes.