--- title: "What does a high IGF-1 mean?" type: biomarker-interpretation url: "https://www.test-well.com/biomarkers/igf-1/high" biomarker: IGF-1 direction: high reference_range: - "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" reviewed_at: 2026-09-08 review_status: reviewed date_published: 2026-09-05 --- # What does a high IGF-1 mean? > 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. ## 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. ## What are the common causes of high IGF-1? 1. Growth hormone therapy, IGF-1 or GH-secretagogue peptides (ipamorelin, CJC-1295, MK-677) 2. Acromegaly — GH-secreting pituitary adenoma 3. Puberty and pregnancy (physiological) 4. Hyperthyroidism (mild) 5. 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 at TestWell: [Prolactin](https://www.test-well.com/tests/prolactin) ($39.99), [Glucose](https://www.test-well.com/tests/glucose-basic) ($14.99). ## How do you recheck IGF-1? | Test or panel | Type | Price | Fasting | Results | | --- | --- | --- | --- | --- | | [Men's Hormone Panel](https://www.test-well.com/tests/mens-hormone-panel) | Panel (7 tests) | $199.99 | No | 3–5 business days | | [Men's Cancer Screening Panel](https://www.test-well.com/tests/mens-cancer-screening-panel) | Panel (12 tests) | $299.99 | Yes | 3–5 business days | | [Women's Cancer Screening Panel](https://www.test-well.com/tests/womens-cancer-screening-panel) | Panel (12 tests) | $299.99 | Yes | 3–5 business days | | [IGF-1 (Insulin-like Growth Factor)](https://www.test-well.com/tests/igf-1-test) | Test | $37.99 | No | 3–5 business days | Plus one $6 lab processing fee per order; physician authorization included. ## 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. ## Related - [What does a low IGF-1 mean?](https://www.test-well.com/biomarkers/igf-1/low) - [IGF-1 reference ranges](https://www.test-well.com/biomarkers/igf-1) - [Total Testosterone reference range](https://www.test-well.com/biomarkers/total-testosterone) - [Free Testosterone reference range](https://www.test-well.com/biomarkers/free-testosterone) - [SHBG reference range](https://www.test-well.com/biomarkers/shbg) ## Sources - [Mayo Clinic Labs](https://www.mayocliniclabs.com/test-catalog/overview/8836) - [MedlinePlus (NIH) — IGF-1 (Insulin-like Growth Factor 1) Test](https://medlineplus.gov/lab-tests/igf-1-insulin-like-growth-factor-1-test/) --- Medically reviewed by Youmna DiStefano, MD (Medical Reviewer, TestWell); last reviewed 2026-09-08. Review policy: https://www.test-well.com/editorial-policy Canonical page: https://www.test-well.com/biomarkers/igf-1/high Machine-readable catalog: https://www.test-well.com/api/catalog.json · MCP server: https://www.test-well.com/mcp · Overview for agents: https://www.test-well.com/llms.txt Prices are cash-pay, in USD, and include physician authorization; every order adds one flat $6 lab processing fee. Educational content is not a diagnosis — discuss results with a clinician.