Insulin is a hormone that is produced and stored in the beta cells of the pancreas. It is secreted in response to elevated blood glucose following a meal and is vital for the transportation and storage of glucose, the body’s main source of energy. Insulin helps transport glucose from the blood to within cells, thus helping regulate blood glucose levels, and has a role in lipid metabolism. This test measures the amount of fasting insulin in the blood. (12 HOURS FASTING)