Other names: insulin C-peptide, connecting peptide insulin, proinsulin C-peptide
C-peptide is a substance made in the pancreas, along with insulin.
What is insulin?
Insulin is a hormone that controls the body's glucose (blood sugar) levels. Glucose is your body's main source of energy. If your body doesn't make the right amount of insulin, it may be a sign of diabetes.
Why test for C-peptide?
C-peptide and insulin are released from the pancreas at the same time and in about equal amounts. So a C-peptide test can show how much insulin your body is making. This test can be a good way to measure insulin levels because C-peptide tends to stay in the body longer than insulin.
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