Type 2 diabetes, the most common form of diabetes worldwide, is a chronic condition that affects the way your body metabolizes sugar (glucose) — an important source of fuel for your body. It is a combination of ineffective insulin and not enough insulin.
Type 2 diabetes develops over a long period of time (a matter of years). During this period of time insulin resistance starts, insulin is increasingly ineffective at managing the blood glucose levels. As a result, the pancreas responds by producing greater and greater amounts of insulin, to try and achieve some degree of management of the blood glucose levels.
Insulin overproduction over a very long period of time eventually tires out the insulin producing cells in the pancreas. So, by the time someone is diagnosed with type 2 diabetes, they have lost 50 – 70% of their insulin producing cells.