The pancreas contains clusters of cells called islets. Beta cells within the islets make insulin and release it into the blood. If beta cells don’t produce enough insulin, or the body doesn’t respond to the insulin that is present, glucose builds up in the blood instead of being absorbed by cells in the body, leading to prediabetes or diabetes. Prediabetes is a condition in which blood glucose levels or A1C levels—which reflect average blood glucose levels—are higher than normal but not high enough to be diagnosed as diabetes. In diabetes, the body’s cells are starved of energy despite high blood glucose levels.