Hormones system

IGF-1 (Insulin-like Growth Factor)

IGF-1

The downstream marker of growth hormone activity — and a longevity research focus.

What is it

IGF-1 (Insulin-like Growth Factor) — in plain English.

IGF-1 is produced primarily by the liver in response to growth hormone. It reflects integrated GH activity over time and is more stable than direct GH measurement.

Why it's measured

What IGF-1 can reveal.

IGF-1 has been studied in research on growth, body composition, and longevity. Both extremes (very high and very low) have been associated with health outcomes in published research.

Reference range

Where most laboratories draw the standard line.

Standard laboratory reference

Age-dependent ng/mL

Reference ranges vary by laboratory. Your individual reference range will appear on your test report and should be interpreted by your physician in the context of your overall health profile.

What results may indicate

Higher vs. lower IGF-1 — at a high level.

Elevated

In adults, may suggest GH excess and warrants clinical evaluation. Acromegaly is a rare cause.

Lower

Has been associated with adult growth hormone deficiency in research literature.

These associations are general. They are not a personal diagnosis or prediction. Discuss your individual results with your physician in the context of your full health profile.

When it's measured

When IGF-1 is typically run.

Used in evaluation of GH status and is a focus of longevity research.

Related markers

Often measured alongside IGF-1.

Measured in

IGF-1 is one of 160 biomarkers in the Apex Panel.

A complete look at your heart, hormones, metabolism, inflammation, and longevity systems — drawn at Quest or LabCorp, reviewed by a U.S.-licensed physician.

Explore the Apex Panel
160 biomarkers13 body systemsPhysician-reviewed
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This information is for general educational purposes only and is not medical advice. Lab results alone are not intended to diagnose, treat, or cure any condition and do not replace the advice of a healthcare provider. OPTML does not offer medical advice, a diagnosis, medical treatment, or any form of medical opinion.