IGF-1
The downstream marker of growth hormone activity — and a longevity research focus.
What is it
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
IGF-1 has been studied in research on growth, and longevity. Both extremes (very high and very low) have been associated with health outcomes in published research.
Reference range
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
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
Used in evaluation of GH status and is a focus of longevity research.
Related markers
Common questions
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.
It's one of the markers used to build a fuller picture of your health. On its own it tells you very little, so it's most informative when reviewed alongside related markers.
It's measured from a standard blood draw at Quest or LabCorp. IGF-1 (Insulin-like Growth Factor) is one of the markers included in the OPTML Apex Panel, where your results are read across systems and reviewed by a U.S.-licensed physician.
Reference ranges vary by laboratory, and a single value rarely tells the whole story. Review your result with a physician in the context of your other markers, symptoms, and history.
IGF-1 (Insulin-like Growth Factor) is one signal among many. Answer a few quick questions and we’ll point you to the panel that fits.
Measured in
A complete look at your heart, hormones, metabolism, inflammation, and longevity systems — drawn at Quest or LabCorp, reviewed by a U.S.-licensed physician.
Find the right panel →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.
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