C- Peptide (Fasting)

Description

The Fasting C-Peptide test measures the level of C-peptide in the blood after an overnight fast, typically 8-12 hours without food. This test provides a baseline assessment of insulin production by the pancreas. C-peptide is produced in equal amounts to insulin, making it an excellent marker for endogenous insulin secretion. The fasting state ensures that the measurement reflects the basal insulin production, without the influence of recent food intake. This test is particularly useful in assessing residual beta cell function in diabetics, differentiating between type 1 and type 2 diabetes, and evaluating insulin resistance. Low fasting C-peptide levels may indicate decreased insulin production, as seen in type 1 diabetes or advanced type 2 diabetes. Conversely, normal or high levels in the presence of hyperglycemia suggest insulin resistance. The test is also valuable in diagnosing insulinomas and monitoring pancreatic function after surgery or in cases of pancreatic disease.