Fasting Insulin Test
How much insulin your pancreas is releasing at rest. High values often indicate insulin resistance.
What is Fasting Insulin?
How much insulin your pancreas is releasing at rest. High values often indicate insulin resistance.
Find a Fasting Insulin test
We offer panels that include this marker. Browse to find the best fit.
Browse testsFasting Insulin Reference Range
These are the typical adult reference ranges used by major US labs. Your report will include the specific range used by the lab that processed your sample.
| Population | Range |
|---|---|
| age 18+, fasting | 2.00 – 20.0 uIU/mL |
Reference ranges are educational. Always interpret your result with the specific range printed on your lab report and discuss anything outside the range with a clinician.
What your Fasting Insulin result may mean
Often reflects insulin resistance, prediabetes, or PCOS.
Educational only — not a diagnosis. Many factors can influence a single result. Discuss anything that concerns you with a healthcare provider.
Sources
Related Diabetes & Blood Sugar biomarkers
Markers commonly tested alongside Fasting Insulin.
Frequently asked
No. TestWell's licensed physician network reviews and approves your order — usually within minutes. You can place an order online without an in-person visit or a referral from your own doctor.
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