Markers › C-Peptide

C-Peptide

MetabolicMetabolism & EnergyBlood

C-peptide is a byproduct the pancreas releases into the body when it makes insulin, and the pancreas produces about the same amount of insulin and C-peptide. A C-peptide test measures the amount of C-peptide in the blood or urine.

Why it matters: Because C-peptide is a byproduct of insulin production, the test can reveal how much insulin the body is producing, and it can tell the difference between insulin made by the body and insulin that came from medication. It can help a provider work out which type of diabetes a person has, and can reveal how well diabetes treatments are working. A C-peptide test cannot determine whether a person has diabetes; it indicates whether the body has the ability to make its own insulin. A low level may be considered normal if blood sugar is low and the person has not eaten recently, and it can also mean the body is not making enough insulin. A high level might mean the body is making too much insulin.

Source · Cleveland Clinic — what it is, why it matters, what moves it, related conditions

Reference Range
1.1 – 4.4ng/mL
1.1
4.4LowNormalHigh
What Moves It

May decrease with:

Insulin taken by injection or inhalation — when people take insulin, their bodies do not make or release C-peptide
Addison disease
Liver disease
Associated Conditions
Type 1 diabetes, which a low level may relate to, especially alongside high blood sugarType 2 diabetes where the pancreas is no longer producing insulin, which a low level may relate toCushing syndrome, which a high level can point toInsulin resistance, which a high level can point toLow levels of potassium in the blood, which a high level can point toType 2 diabetes, which a high level can also point toPancreatic tumour, or insulinoma, which a high level can point toKidney failure, which a high level can point to
Related Markers
InsulinGlucoseHbA1c
Common questions

What is C-Peptide?

C-peptide is a byproduct the pancreas releases into the body when it makes insulin, and the pancreas produces about the same amount of insulin and C-peptide. A C-peptide test measures the amount of C-peptide in the blood or urine.

What might a high or low C-Peptide mean?

Because C-peptide is a byproduct of insulin production, the test can reveal how much insulin the body is producing, and it can tell the difference between insulin made by the body and insulin that came from medication. It can help a provider work out which type of diabetes a person has, and can reveal how well diabetes treatments are working. A C-peptide test cannot determine whether a person has diabetes; it indicates whether the body has the ability to make its own insulin. A low level may be considered normal if blood sugar is low and the person has not eaten recently, and it can also mean the body is not making enough insulin. A high level might mean the body is making too much insulin.

What is the typical reference range for C-Peptide?

The general-population reference range shown here is 1.1 – 4.4 ng/mL. Reference ranges describe the general population and are not a personal target — discuss your results with your physician.

What can affect C-Peptide?

It may be lower with: Insulin taken by injection or inhalation — when people take insulin, their bodies do not make or release C-peptide, Addison disease, Liver disease.

More in Metabolic
GlucoseHbA1cHbA1c (IFCC)HOMA-IRInsulin

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