Professional lab technician performing blood test
NutritionFasting Required

Fasting Insulin

Results in 1–2 days
CLIA-certified laboratory
4,500+ locations nationwide
$53one-time, no hidden fees

About this test

The Fasting Insulin test measures the level of insulin in your blood after a period of fasting, offering critical insight into how efficiently your body uses insulin. Elevated fasting insulin levels can signal insulin resistance, often years before blood sugar levels rise, making this test a powerful early indicator of metabolic dysfunction.  This test measures fasting insulin levels to evaluate how much insulin your body must produce to maintain normal blood sugar. Please fast 8 hours before this test.

What's included

Fasting Insulin

Fasting Glucose

Hemoglobin A1C (HbA1c)

What each biomarker measures

Click any marker to learn what it tests and why it matters for your health.

Why fasting insulin testing matters

  • Insulin resistance can develop years before blood sugar rises — this test catches it first
  • High fasting insulin is linked to weight gain, fatigue, and increased diabetes risk
  • Helps guide dietary and lifestyle interventions before medication becomes necessary
  • Especially valuable for anyone with PCOS, metabolic syndrome, or a family history of diabetes

Fasting required

Please fast for 8 hours before your lab visit. Water is fine. Avoid food, coffee, and juice.

Test summary

  • Price$53
  • Turnaround1–2 days
  • CategoryNutrition
  • Sample typeBlood draw / urine
  • Tests included3 biomarkers
  • FastingRequired (8 hrs)
  • PrescriptionNot required
Find a lab near you

How it works

01

Order online

Select your test and complete checkout in minutes. No doctor visit needed.

02

Visit a lab

We will help you select a partner lab. Walk into any of 4,500+ Quest or LabCorp locations with your requisition form.

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03

Get results

Receive secure, confidential results online in 1–2 days.

CLIA-certified labs
No doctor visit required
Results in 1–2 days
4,500+ locations

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Ready to take control of your health?

No doctor visit. No insurance. No waiting room. Order your Fasting Insulin today.

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