An insulin level test measures the amount of insulin in your blood. Insulin is a hormone produced by the pancreas that helps your body use sugar (glucose) for energy. This test can be used to:   Diagnose insulin resistance: A condition where your body doesn't respond properly to insulin.   Help diagnose type 2 diabetes: Often associated with insulin resistance.   Evaluate certain pancreatic conditions: Such as insulinomas (tumors that produce insulin).   Types of Insulin Level Tests: Fasting Insulin Level: Measures insulin levels after an overnight fast (usually 8-10 hours).   Postprandial Insulin Level: Measures insulin levels two hours after a meal.