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Metabolic

C-Peptide Blood Test

C-Peptide reveals how effectively your pancreas produces insulin. Optimal insulin function supports energy, body composition, and metabolic performance.

Doctor's Assessment Included

C-Peptide: what this test measures

This test measures the level of C-Peptide in your blood. Since C-Peptide is produced in equal amounts to insulin, it reliably reflects your pancreas's insulin-producing capacity.

C-Peptide: why this value matters

C-Peptide helps distinguish between type 1 and type 2 diabetes and assesses how well the pancreas is functioning. It can also help evaluate insulin resistance. Consult your healthcare provider for interpretation.

C-Peptide: how to prepare

  1. Pause biotin

    Required

    Do you take a supplement with biotin (vitamin B8, common in hair, skin and nail supplements)? Stop it 72 hours before the draw. Biotin interferes with the measurement of these values.

  2. Come fasting

    Required

    From 22:00 the evening before, eat and drink nothing except water. That is at least 8 hours. Skip coffee, tea, chewing gum and smoking that morning. Plan the draw before 10:00.

  • Water is always fine. Drink as usual beforehand, it makes the draw easier.
  • Take your usual medication, unless your own doctor told you otherwise.

C-Peptide: when is testing worthwhile?

Testing may be recommended to evaluate pancreatic function, distinguish diabetes types, monitor insulin-producing tumours, or assess unexplained low blood sugar episodes.

C-Peptide: symptoms of a high or low value

Low Levels

Low C-Peptide may indicate that the pancreas is producing little or no insulin, which is typical of type 1 diabetes. Symptoms may include excessive thirst, frequent urination, and weight loss.

High Levels

High C-Peptide may indicate insulin resistance, type 2 diabetes, or an insulin-producing tumour. Symptoms may include weight gain, fatigue, and difficulty managing blood sugar levels.

C-Peptide: lifestyle and this value

Regular physical activity, a balanced diet with controlled carbohydrate intake, maintaining a healthy weight, and managing stress can all support healthy insulin function and C-Peptide levels.

C-Peptide: frequently asked questions

Why test C-Peptide instead of insulin?

C-Peptide is more stable in the blood and is not affected by injected insulin, making it a more reliable measure of your body's own insulin production.

Can C-Peptide help diagnose diabetes type?

Yes, low C-Peptide suggests type 1 diabetes (insufficient production), while high levels may suggest type 2 diabetes (overproduction due to resistance). Your healthcare provider can confirm.

Do I need to fast for this test?

Fasting may be required depending on the clinical question. Your healthcare provider will advise on preparation.

Tests with related values

These panels measure values from the same category as this marker.

Health Checkups

Complete Men's Health Panel

A broad men's health panel: hormones, heart, metabolic, and organ function in one blood draw.

HbA1c (Glycated Hemoglobin) ALT (Alanine Aminotransferase) TSH (Thyroid Stimulating Hormone) Triglycerides Creatinine Glucose (Fasting) Free T4 (Thyroxine) LDL Cholesterol SHBG (Sex Hormone Binding Globulin) Total Cholesterol Vitamin D (25-OH) Free Testosterone Total Testosterone Ferritin hs-CRP (High Sensitivity CRP) HDL Cholesterol
€289,-

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C-Peptide

€91,-