IGF-1 · high result
What does a high IGF-1 mean?
Short answer
High IGF-1 means the liver is receiving a strong growth-hormone signal. In adults the important cause is acromegaly — a pituitary tumor over-producing growth hormone — but supplemental growth hormone or IGF-1, peptide products marketed for muscle and recovery, puberty and pregnancy also raise it. Because IGF-1 is stable through the day it is the screening test of choice; a high value is confirmed with a glucose-suppressed GH test.
Medically reviewed by Youmna DiStefano, MD · Last reviewed September 2026
When does this result need same-day care?
- New vision loss or severe persistent headaches with a high IGF-1 — prompt evaluation for a pituitary mass
What is the normal range for IGF-1?
- age 18–30: 116 – 358 ng/mL
- age 31–50: 94.0 – 252 ng/mL
- age 51–70: 81.0 – 225 ng/mL
- age 71+: 53.0 – 175 ng/mL
Can reflect excess growth hormone (e.g. pituitary adenoma). Used in evaluating acromegaly.
Full reference table, citations and testing options: IGF-1 biomarker page.
What are the common causes of high IGF-1?
- Growth hormone therapy, IGF-1 or GH-secretagogue peptides (ipamorelin, CJC-1295, MK-677)
- Acromegaly — GH-secreting pituitary adenoma
- Puberty and pregnancy (physiological)
- Hyperthyroidism (mild)
- Lab variation: assays and age bands differ — compare within one lab
What symptoms go with high IGF-1?
- Often none
- Enlarging hands and feet, ring or shoe size going up, coarser facial features, jaw growth
- Headaches, sweating, joint pain, snoring or sleep apnea, carpal tunnel symptoms
What do clinicians usually check next?
- Repeat with the same lab; review any supplements, peptides or GH use
- Oral glucose tolerance test with GH measurement — the confirmatory test when acromegaly is possible
- Pituitary MRI, prolactin and other pituitary hormones if GH fails to suppress
- A1c and glucose — excess GH raises blood sugar
Follow-up tests available at TestWell: Prolactin ($39.99), Glucose ($14.99).
How do you recheck IGF-1?
Prices are cash-pay; every order adds one $6 lab processing fee. Physician authorization is included; no insurance or referral needed.
| Test or panel | Type | Price | Fasting | Results |
|---|---|---|---|---|
| Men's Hormone Panel | Panel · 7 tests | $199.99 | No | 3–5 business days |
| Men's Cancer Screening Panel | Panel · 12 tests | $299.99 | Yes | 3–5 business days |
| Women's Cancer Screening Panel | Panel · 12 tests | $299.99 | Yes | 3–5 business days |
| IGF-1 (Insulin-like Growth Factor) | Test | $37.99 | No | 3–5 business days |
Common questions
Can peptides or supplements raise IGF-1?
Yes. GH secretagogues (ipamorelin, CJC-1295, MK-677, sermorelin) and injected GH or IGF-1 raise it directly; that's the intended effect and a common reason people test. Tell the clinician what you take — a high value on a peptide is expected, off everything it's a pituitary question.
What IGF-1 level suggests acromegaly?
Any value above the age-adjusted upper limit without an explanation (puberty, pregnancy, GH use) warrants a glucose-suppression GH test. The higher above range, the more likely; no single cutoff diagnoses it.
Educational content, not a diagnosis. Lab results are one input; a clinician interprets them with your history and exam.