The cause is usually from being over weight and a typical American diet high in fat and carbohydrate. Lack of exercise also plays a role in weight gain and in turn the onset of type 2 diabetes. Our cells have receptor sites on their surfaces. These sites are like docking stations that allow specific substances to lock on and activate processes inside the cells. The more receptor sites on the cell surface, the more efficiently the substance can stimulate cell activity.
Obesity can cause the number of receptors for insulin to decrease.
Losing weight causes the number of these receptors to increase. Some people with type 2 diabetes have the right number of insulin receptors, but they don't work properly. Because it can take so long to develop, and because the body continues to produce insulin, type 2 diabetes often goes undiagnosed for years. Often some of the complications of Chronically high blood sugar have developed by the time the diagnosis of diabetes is made. But with good blood sugar control, you may avoid any further complications.