Why include C-Peptide if we already test insulin?

C-Peptide is produced in equal amounts to insulin but is not affected by external insulin use. It provides a more accurate measure of your pancreas's own insulin production and helps distinguish Type 1 from Type 2 diabetes.

What is insulin resistance?

Insulin resistance means your cells don't respond well to insulin, forcing your pancreas to produce more. Over time this leads to weight gain, elevated blood sugar, and eventually diabetes. It's reversible with lifestyle changes when caught early.

The CMP provides liver and kidney function markers that are often affected by metabolic dysfunction. Elevated liver enzymes can indicate fatty liver disease, which is closely linked to insulin resistance.

How is this different from the Comprehensive Diabetes Panel?

This panel adds C-Peptide and CMP for a deeper look at insulin production and organ function. The Diabetes Panel focuses on glucose control and lipids. Choose this panel if you want the most thorough insulin resistance assessment.

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Panel🩸 Diabetes

Insulin Resistance Panel - Metabolic Health Assessment

This panel detects insulin resistance at every stage — from early pancreatic overproduction to full metabolic dysfunction. C-Peptide and fasting insulin together reveal how hard your pancreas is working.

Insulin resistance is the root cause of type 2 diabetes, metabolic syndrome, and a major driver of heart disease. This panel provides the most complete picture of insulin function available:

• Fasting Glucose - Your blood sugar right now • Fasting Insulin - How much insulin your pancreas needs to control blood sugar • HbA1c - Your average blood sugar over 2-3 months • C-Peptide - A direct measure of how much insulin your pancreas produces • Comprehensive Metabolic Panel - Liver, kidney, and electrolyte function

The combination of insulin and C-Peptide is particularly powerful: insulin levels can be affected by external insulin use, but C-Peptide reflects only what your body produces. Together they give the clearest picture of metabolic health.

Panel Price

$45

All-in

$63

incl. $18 lab & physician fee

You Save

$1.50

Biomarkers

5 tests

Included Tests

Glucose, Fasting

Measures blood sugar levels after fasting. Used to screen for diabetes and monitor blood sugar control.

Glucose

Fasting

Insulin, Fasting

Measures fasting insulin levels to assess insulin resistance and metabolic health. Important for early detection of diabetes risk.

Insulin

$14

Fasting

Hemoglobin A1c (HbA1c)

Measures average blood sugar over the past 2-3 months. Key marker for diabetes management and prediabetes screening.

HbA1cEstimated Average Glucose

C-Peptide

Measures insulin production by the pancreas. Helps distinguish Type 1 from Type 2 diabetes.

C-Peptide

$10

Fasting

Comprehensive Metabolic Panel

Measures 14 substances including glucose, electrolytes, kidney and liver function markers.

GlucoseBUNCreatinineeGFR+12 more

$9.50

Fasting

Fasting Required

One or more tests in this panel require fasting for accurate results:

Do not eat or drink anything except water for 8-12 hours before your blood draw.
Water is allowed and encouraged - stay hydrated!
Schedule your lab visit in the morning for convenience.

What This Panel Measures

This panel measures fasting glucose (current blood sugar), fasting insulin (insulin resistance marker), HbA1c (2-3 month blood sugar average), C-Peptide (endogenous insulin production), and 14 CMP markers (glucose, electrolytes, kidney and liver function).

Who Should Get This Panel

Anyone with weight concerns, family history of diabetes, PCOS, metabolic syndrome symptoms, or those wanting to detect insulin resistance before blood sugar becomes elevated. Also valuable for monitoring progress on dietary or lifestyle interventions.

Health Insights

Conditions Screened

Insulin resistancePrediabetesType 2 diabetesType 1 diabetesMetabolic syndromePCOS-related metabolic dysfunctionHyperinsulinemia

Related Symptoms

Weight gainDifficulty losing weightFatigue after mealsSugar cravingsBrain fogIncreased thirstFrequent urinationDarkened skin patches

When to Get Tested

Fasting for 10-12 hours is required for accurate insulin, glucose, and C-Peptide results. Schedule for morning. Retest every 3-6 months if monitoring lifestyle changes.

Understanding Your Results

Key targets: Fasting glucose <100 mg/dL, HbA1c <5.7%, Fasting insulin <10 µIU/mL, C-Peptide 0.8-3.1 ng/mL. Elevated insulin with normal glucose = early insulin resistance. Elevated C-Peptide confirms your pancreas is overproducing insulin.

How much does the Insulin Resistance Panel cost?

The Insulin Resistance Panel costs $45 at JustLabs — $63 all-in, since the $18 lab & physician order fee is charged once per order, however many tests you add. The price is fixed before your blood draw; no insurance or doctor visit needed.

Option	Price	Order all-in	Notes
Insulin Resistance Panel at JustLabsDrawn at Quest Diagnostics	$45	$63	Includes the one $18 fee, charged once per order
The same 5 tests ordered individually	$46.50	$64.50	The panel saves $1.50

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