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Insulin-like Growth Factor 1 (IGF-1)

Published: July 27, 2026Updated: August 25, 2026

IGF-1 measures a hormone similar to insulin that plays a crucial role in growth and development, particularly during puberty.

Quick summary

IGF-1 is a key biomarker for assessing growth hormone activity and overall growth potential.

Medically reviewed by WellAlly Editorial TeamLast reviewed August 25, 2026Editorial policy

Key facts at a glance

Units
ng/mL
Clinical utility
diagnostic
Result kind
quantitative
FDA-cleared
Roche IGF-1, Abbott IGF-1, Siemens IGF-1, MediBIR IGF-1
interpretation: {"text":"May indicate growth hormone deficiency, malnutrition, or chronic diseases. Further evaluation is needed to confirm the underlying cause.","label":"Low Levels"}; {"text":"May suggest acromegaly, gigantism, or other conditions with excess growth hormone. Additional tests are often required for a definitive diagnosis.","label":"High Levels"}

IGF-1, or Insulin-like Growth Factor 1, is a hormone primarily produced by the liver in response to growth hormone stimulation. It is essential for normal growth and development, especially during childhood and adolescence.

This biomarker is often used in the diagnosis and monitoring of growth disorders, such as acromegaly and growth hormone deficiency. It provides a more stable measure of growth hormone activity compared to direct growth hormone measurements.

IGF-1 levels are also indicative of nutritional status and can be affected by factors such as age, sex, and overall health. Reference ranges typically fall between 100–400 ng/mL, but these can vary based on individual characteristics.

Frequently asked questions

What factors can affect IGF-1 levels?
Age, sex, nutritional status, and overall health can all influence IGF-1 levels. Certain medications and medical conditions can also impact results.
How is an IGF-1 test performed?
An IGF-1 test involves a simple blood draw. It is often performed in the morning after an overnight fast to ensure accurate results.
  1. 1
    National Institute of Diabetes and Digestive and Kidney DiseasesSource
  2. 2
    Mayo ClinicSource

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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

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Medically reviewed by WellAlly Editorial Team Last reviewed August 25, 2026. · Read our editorial policy