Fasting insulin

FASTING INSULIN

Insulin is a hormone produced and secreted by the beta cells in the pancreas. The body secretes insulin as a response to elevated blood glucose levels caused by eating or cortisol secretion due to increased stress. Insulin increases glucose absorption and storage and the synthesis of fatty acids and proteins while inhibiting the breakdown of proteins and fatty acids. High insulin levels are connected to insulin resistance, obesity, metabolic syndrome, insulinoma, Cushing’s syndrome, excessive insulin, or corticosteroid doses. Low insulin levels are connected to diabetes, hypopituitarism and various pancreatic illnesses.

Ideally, the fasting insulin level should be at the lower end of the reference range. Insulin inhibits lipolysis or the breakdown of fat into energy. If the body's stored insulin levels are consistently elevated, the fatty acids circulating in the blood are stored in the adipose tissue. This is called lipogenesis. In particular, insulin secretion is stimulated by high blood sugar levels and a carbohydrate-rich diet. Abundant protein intake also increases insulin secretion. Due to these factors, the fasting insulin level should be quite low, in the lower half of the reference range. High insulin levels may also be a predisposing factor for the chronic diseases discussed in the description of the HbA1C value.

• Reference range: 2.0–20 mIU/L