IGF-1 is the primary mediator of growth hormone effects in the body, reflecting overall growth hormone status and important for metabolism, muscle, and bone health.
Insulin-like Growth Factor 1 (IGF-1) is a hormone primarily produced by the liver in response to growth hormone (GH). Unlike growth hormone which fluctuates throughout the day, IGF-1 levels remain stable, making it the best marker for assessing overall growth hormone status.
IGF-1 plays crucial roles in growth during childhood, muscle and bone maintenance in adults, and metabolic health. It promotes protein synthesis, supports muscle growth, and helps regulate body composition.
IGF-1 levels naturally decline with age. Low levels are associated with decreased muscle mass, increased body fat, reduced bone density, and lower energy. However, both very low and very high IGF-1 levels can indicate health concerns.
Price
$24
Results
2-3 days
Lab Network
Quest
Fasting
Not Required
What's Measured
What This Test Measures
This test measures the blood concentration of IGF-1, reported in ng/mL. Normal ranges vary by age and sex. IGF-1 reflects integrated growth hormone secretion over time, providing a stable indicator of GH status.
Who Should Consider This Test
Adults interested in growth hormone status, those with symptoms of GH deficiency, people concerned about age-related hormone decline, athletes and fitness enthusiasts, individuals with unexplained fatigue or muscle loss, and those evaluating pituitary function.
Health Insights
Conditions Screened
Related Symptoms
When to Get Tested
No fasting required. IGF-1 levels are stable throughout the day, so timing doesn't matter. Avoid testing during acute illness as levels may be temporarily affected.
Understanding Your Results
Normal IGF-1 varies significantly by age. Typical adult ranges: Ages 20-30: 115-350 ng/mL, Ages 30-40: 115-310 ng/mL, Ages 40-50: 95-250 ng/mL, Ages 50+: 70-210 ng/mL. Results should be interpreted with age-specific references.
What to Expect
After placing your order, you'll receive an email from Rupa Health (our lab order partner) within 24 business hours to sign a consent form and schedule your blood draw at a Quest Diagnostics location.
The blood draw typically takes just a few minutes. Results are usually available within 2-3 business days and will appear in your secure Justlabs dashboard.
Our results include reference ranges and easy-to-understand indicators showing whether your values are within normal limits.
Frequently Asked Questions
$24
Typical hospital cash price: $120–$180
+ $28 in standard lab & physician fees at checkout (no additional bills later)
$18 lab collection + $10 physician order
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