Insulin is a hormone produced by the pancreas that regulates blood sugar levels by helping cells absorb glucose from the bloodstream. This test measures insulin levels in the blood and is primarily used to evaluate insulin production and diagnose conditions related to abnormal insulin secretion. The test is particularly useful for diagnosing insulinoma, a rare pancreatic tumor that produces excessive insulin, causing hypoglycemia. It's also used to assess insulin resistance, which is common in type 2 diabetes and metabolic syndrome. Insulin levels can help distinguish between different types of hypoglycemia and evaluate pancreatic function. This test is commonly ordered when patients experience unexplained low blood sugar, when evaluating suspected pancreatic disorders, or when assessing insulin sensitivity in metabolic conditions. Understanding insulin levels is crucial for proper diabetes management and can help guide treatment decisions.