IGF-1
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 business days
Lab Network
Quest
Fasting
Not Required
What's Measured
IGF-1 LC/MS
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
Growth hormone deficiencyGrowth hormone excess (acromegaly)Pituitary disordersAge-related hormone declineNutritional status
Related Symptoms
Fatigue and low energyDecreased muscle massIncreased body fatPoor exercise recoveryReduced bone densityDecreased sense of wellbeing
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 Fullscript (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.
$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
Results in 2-3 business days
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