IGF-I

Name: IGF-I Test: Reference Ranges & Analysis
Creator: Health3 AG
Published: 2025-12-11

Content Source: Health3 AG
Data Compiled From: Clinical laboratory standards & peer-reviewed research
Quality Assurance: Verified against multiple authoritative sources
Academic Sources: Rifai, 2023; Alte, 2008; Barati, 2022; Bodine, 2001; Clemmons, 2012; Friedrich, 2012; Arnoux, 2016; Friedrich, 2012; Clemmons, 2004
Last Verified: 2025-12-11
Our Content Standards & Medical Disclaimer

What is IGF-I?

Insulin-like Growth Factor 1 (IGF-I) is a hormone similar in molecular structure to insulin and plays a crucial role in childhood growth and continues to have anabolic effects in adults. It is produced primarily in the liver and stimulated by growth hormone (GH) released from the pituitary gland. IGF-I aids in promoting normal bone and tissue growth and development. In adults, it has anabolic effects, which include muscle growth, repair, and metabolism. It also influences cell growth and development, affecting various bodily functions.

Low levels of IGF-I, can indicate growth hormone deficiency, leading to stunted growth and delayed development. In adults, low IGF-I levels can result in decreased bone density and muscle weakness, contributing to a higher risk of osteoporosis and fractures. Lower levels of IGF-I are often observed in aging adults and can be associated with reduced muscle mass and strength, known as sarcopenia. Causes of low IGF-I can include malnutrition, hormonal imbalances, liver disease, and genetic factors affecting growth hormone production.

Elevated levels of IGF-I are less common and can be associated with excessive growth hormone production, as seen in conditions like acromegaly. This condition, usually due to a benign tumor in the pituitary gland, can lead to abnormal growth of the hands, feet, and face in adults. High levels of IGF-I might also contribute to insulin resistance and are being studied for their potential association with an increased risk of certain cancers, although this relationship is not yet fully understood.

Both high and low levels of IGF-1 have been associated with an increased all-cause mortality risk, with a mid-range being associated with the lowest mortality.

To maintain healthy IGF-I levels:

Engage in regular physical activity and exercise, as it can help stimulate growth hormone production and, consequently, IGF-I levels.
Ensure adequate sleep, as growth hormone is primarily released during deep sleep. Aim for 7-9 hours of quality sleep per night.
Maintain a balanced diet rich in protein, as it is essential for the production of IGF-I and the growth and repair of tissues.
Manage stress levels through relaxation techniques, as chronic stress can negatively impact growth hormone and IGF-I production.

Measurement Units

IGF-I can be measured in: ng/mL, nmol/L, µg/100mL, µg/dL, µg/L, µg%

Reference Ranges by Age and Gender

Reference ranges represent typical values for healthy individuals. Your healthcare provider must interpret your specific results.

Age Range	Gender	Unit	Optimal	Normal	Source
All ages	All genders	ng/mL	-	120 - 160	Barati, 2022
18 - 20	Woman	ng/mL	-	155 - 585	Arnoux, 2016
18 - 20	Man	ng/mL	-	168 - 537	Arnoux, 2016
19 - 25	Woman	ng/mL	-	231 - 550	Rifai, 2023
19 - 25	Man	ng/mL	-	202 - 433	Rifai, 2023
20 - 24	Woman	ng/mL	-	111 - 423	Alte, 2008
20 - 24	Man	ng/mL	-	156 - 385	Alte, 2008
21 - 23	Woman	ng/mL	-	144 - 541	Arnoux, 2016
21 - 23	Man	ng/mL	-	147 - 477	Arnoux, 2016
24 - 26	Woman	ng/mL	-	134 - 501	Arnoux, 2016
24 - 26	Man	ng/mL	-	132 - 430	Arnoux, 2016
25 - 29	Woman	ng/mL	-	102 - 360	Alte, 2008
25 - 85	Woman	ng/mL	-	135 - 449	Rifai, 2023
25 - 85	Man	ng/mL	-	135 - 449	Rifai, 2023
25 - 29	Man	ng/mL	-	119 - 343	Alte, 2008
27 - 29	Woman	ng/mL	-	126 - 467	Arnoux, 2016
27 - 29	Man	ng/mL	-	122 - 396	Arnoux, 2016
30 - 34	Woman	ng/mL	-	94 - 309	Alte, 2008
30 - 39	Woman	ng/mL	-	113 - 403	Arnoux, 2016
30 - 34	Man	ng/mL	-	97 - 306	Alte, 2008
30 - 39	Man	ng/mL	-	108 - 348	Arnoux, 2016
35 - 39	Woman	ng/mL	-	86 - 271	Alte, 2008
35 - 39	Man	ng/mL	-	84 - 275	Alte, 2008
40 - 44	Woman	ng/mL	-	79 - 246	Alte, 2008
40 - 49	Woman	ng/mL	-	97 - 331	Arnoux, 2016
40 - 44	Man	ng/mL	-	76 - 251	Alte, 2008
40 - 49	Man	ng/mL	-	91 - 301	Arnoux, 2016
45 - 49	Woman	ng/mL	-	73 - 232	Alte, 2008
45 - 49	Man	ng/mL	-	71 - 233	Alte, 2008
50 - 54	Woman	ng/mL	-	68 - 228	Alte, 2008
50 - 59	Woman	ng/mL	-	80 - 271	Arnoux, 2016
50 - 59	Man	ng/mL	-	81 - 273	Arnoux, 2016
50 - 54	Man	ng/mL	-	66 - 221	Alte, 2008
55 - 59	Woman	ng/mL	-	64 - 231	Alte, 2008
55 - 59	Man	ng/mL	-	61 - 214	Alte, 2008
60 - 69	Woman	ng/mL	-	64 - 227	Arnoux, 2016
60 - 64	Woman	ng/mL	-	61 - 237	Alte, 2008
60 - 69	Man	ng/mL	-	75 - 260	Arnoux, 2016
60 - 64	Man	ng/mL	-	55 - 211	Alte, 2008
65 - 69	Woman	ng/mL	-	59 - 241	Alte, 2008
65 - 69	Man	ng/mL	-	49 - 209	Alte, 2008
70 - ∞	Woman	ng/mL	-	56 - 204	Arnoux, 2016
70 - 74	Woman	ng/mL	-	57 - 237	Alte, 2008
70 - ∞	Man	ng/mL	-	64 - 242	Arnoux, 2016
70 - 74	Man	ng/mL	-	46 - 207	Alte, 2008
75 - ∞	All genders	ng/mL	-	55 - 219	Alte, 2008
75 - ∞	Man	ng/mL	-	48 - 202	Alte, 2008

Health Impact

Blood Sugar Regulation

Although primarily associated with growth, IGF-1 can also influence insulin sensitivity and glucose metabolism. Its role in blood sugar regulation is intertwined with that of insulin.^{[Clemmons, 2012]}^{[Friedrich, 2012]}^{[Clemmons, 2004]}

Premium

1 More Health Topic Available

Explore 1 additional health topic related to this biomarker in the Health3 app.

Academic References

Rifai N.. Tietz Textbook of Laboratory Medicine (2023). Elsevier.
Alte D, Friedrich N, Kohlmann T, Lerch MM, Lüdemann J, Nauck M, Spilcke-Liss E, Völzke H, and Wallaschofski H. Reference ranges of serum IGF-1 and IGFBP-3 levels in a general adult population: results of the Study of Health in Pomerania (SHIP) (2008). Growth Horm IGF Res. DOI: 10.1016/j.ghir.2007.09.005
Barati M, Bawadi H, Christensen K, Giovannucci E, Kopchick JJ, Lagani V, Laviano A, Longo VD, Mirisola MG, Montesanto A, Passarino G, Rahmani J, Vardavas R, and Zand H. Association between IGF-1 levels ranges and all-cause mortality: A meta-analysis (2022). Aging Cell. DOI: 10.1111/acel.13540
Bodine SC, Clarke BA, Glass DJ, Nunez L, Rommel C, Rossman R, Stitt TN, and Yancopoulos GD. Mediation of IGF-1-induced skeletal myotube hypertrophy by PI(3)K/Akt/mTOR and PI(3)K/Akt/GSK3 pathways (2001). Nat Cell Biol. DOI: 10.1038/ncb1101-1009
Clemmons DR. Metabolic actions of insulin-like growth factor-I in normal physiology and diabetes (2012). Endocrinol Metab Clin North Am. DOI: 10.1016/j.ecl.2012.04.017
Friedrich N, Jørgensen T, Juul A, Linneberg A, Spielhagen C, Thuesen B, and Wallaschofksi H. The association between IGF-I and insulin resistance: a general population study in Danish adults (2012). Diabetes Care. DOI: 10.2337/dc11-1833
Arnoux Armelle, Brailly-Tabard Sylvie, Chanson Philippe , Massart Catherine, Mavromati Maria, Piketty Marie-Liesse, Souberbielle Jean-Claude, and Young Jacques. Reference Values for IGF-I Serum Concentrations: Comparison of Six Immunoassays (2016). The Journal of Clinical Endocrinology & Metabolism. DOI: 10.1210/jc.2016-1257
Friedrich N, Jørgensen T, Juul A, Linneberg A, Spielhagen C, Thuesen B, and Wallaschofksi H. The association between IGF-I and insulin resistance: a general population study in Danish adults (2012). Diabetes Care. DOI: 10.2337/dc11-1833
Clemmons DR. Role of insulin-like growth factor iin maintaining normal glucose homeostasis (2004). Horm Res. DOI: 10.1159/000080763

Save this biomarker reference for your medical appointments

Was this information helpful?

Track IGF-I in Health3

Monitor your biomarkers, visualize trends, and share insights with your care team.