C Peptide (Fasting)

A C-Peptide (Fasting) test measures the amount of C-peptide in a sample of your blood after you have refrained from eating or drinking (except water) for a specific period, usually 8 to 12 hours.

C-peptide is a byproduct created when the pancreas produces insulin. Insulin and C-peptide are released into the bloodstream in equal amounts. Therefore, measuring C-peptide is an accurate, indirect way to see exactly how much insulin your pancreas is naturally producing.