C-Peptide
A byproduct of insulin production — reflects how much insulin the pancreas is making.
What is it
C-peptide is released alongside insulin when the pancreas produces the hormone. Because it has a longer half-life than insulin, it provides a more stable view of pancreatic insulin output.
Why it's measured
C-peptide has been used in research and clinical practice to evaluate pancreatic beta-cell function.
Reference range
Standard laboratory reference
0.8 – 3.1 ng/mL
Reference ranges vary by laboratory. Your individual reference range will appear on your test report and should be interpreted by your physician in the context of your overall health profile.
What results may indicate
Elevated
Has been associated with insulin resistance and elevated insulin production in research literature.
Lower
Has been associated with reduced pancreatic insulin output in research literature.
These associations are general. They are not a personal diagnosis or prediction. Discuss your individual results with your physician in the context of your full health profile.
When it's measured
Used in evaluating pancreatic function and distinguishing types of diabetes.
Related markers
Measured in
A complete look at your heart, hormones, metabolism, inflammation, and longevity systems — drawn at Quest or LabCorp, reviewed by a U.S.-licensed physician.
Explore the Apex Panel →This information is for general educational purposes only and is not medical advice. Lab results alone are not intended to diagnose, treat, or cure any condition and do not replace the advice of a healthcare provider. OPTML does not offer medical advice, a diagnosis, medical treatment, or any form of medical opinion.