Indicator Explainer
C Peptide
C peptide (31 aa, ~3 kDa) is encoded by the human INS gene. This protein is involved in both signal transduction and the modulation of blood flow.
This page explains what the indicator is and how results are interpreted in general terms. Reference ranges depend on the laboratory, the method, and your own situation — no single “normal value” applies to everyone. This page is health information, not a diagnosis. For symptoms, treatment, or urgent concerns, contact a healthcare professional.
When it is tested
Source: National Cancer Institute, NCI Thesaurus 26.09d, C94608. NCI definition, reproduced without modification under CC BY 4.0. Source identity and definition checked automatically on 2026-10-18. No individual clinical interpretation or human reviewer is asserted.
Reading results
Reference intervals and interpretation depend on the laboratory, specimen, method and clinical context. This source definition is educational information; it does not establish a diagnosis, product approval or suitability for an individual.
Also Known As
Related Tests
Tests that measure or involve this indicator.
References
- NCI Thesaurus 26.09d — C Peptide (C94608)
- Source: National Cancer Institute, NCI Thesaurus 26.09d, C94608. NCI definition, reproduced without modification under CC BY 4.0.
- C-Peptide Provides Critical Contextual Insight Into Elevated Glucose Values During Progression to Type 1 Diabetes. — Diabetes Care, 2026-10-01 (PMID 42060373; literature)
- The Importance of C-Peptide for Developing T1D Disease-Modifying Therapies. — Diabetes Care, 2026-10-01 (PMID 42008285; literature)
- Disease duration and C-peptide at onset are key determinants of long-term residual β-cell function in children with type 1 diabetes. — J Pediatr Endocrinol Metab, 2026-10-23 (PMID 42910515; literature)
- Evaluation of the commutability of control materials for C-peptide proficiency testing. — Clin Chim Acta, 2026-10-18 (PMID 42893716; literature)
- The low fasting serum C-peptide level was associated with reduced sural nerve action potential amplitudes: A cross-sectional study of Japanese type 2 diabetes. — J Diabetes Investig, 2026-10-28 (PMID 42952199; literature)