About IGF-1
Binds IGF-1R with high affinity, activating PI3K/Akt and MAPK pathways promoting protein synthesis, satellite cell activation, and glucose uptake. Much shorter half-life (~15 min) than the LR3 analog (~20-30 hr) due to binding protein interactions.
IGF-1 (insulin-like growth factor 1; somatomedin C) is an endogenous 70-amino-acid polypeptide produced primarily in the liver in response to growth hormone signaling, functioning as the principal mediator of GH anabolic effects through its receptor (IGF-1R) expressed in virtually all tissues, with roles in muscle protein synthesis, bone growth, and cellular proliferation. IGF-1 activates IGF-1R tyrosine kinase to stimulate PI3K/Akt and MAPK/ERK signaling cascades, promoting protein synthesis, cell survival, and glucose uptake in muscle and bone; endogenous IGF-1 levels peak during puberty and decline with age, and GH-stimulating interventions exert many of their effects by elevating circulating IGF-1. The FDA-approved recombinant form, mecasermin (Increlex), is indicated for primary IGF-1 deficiency in children with GH receptor insensitivity syndrome, with multicenter controlled clinical trials demonstrating significant height velocity improvements in this rare pediatric population; this approved indication is specific to a defined hormonal insufficiency condition and is distinct from performance-enhancing or anti-aging uses of exogenous IGF-1. Research-grade IGF-1 is available as a compounded or gray-market compound used outside its approved indication; it is not approved for adult use or performance applications, and risks associated with IGF-1 excess — including effects on glucose homeostasis, potential oncogenic cell signaling, and acromegaly-related comorbidities — are relevant safety considerations for any off-label use.
IGF-1 Benefits & Research Areas
Regulatory & Evidence
Risk Profile
Moderate risk profile in research contexts. Review contraindications and administration guidelines before use.
Regulatory Status
- Availability Status
- Research Only
Regulatory status reflects publicly available information and may change. This is not legal or medical advice.
Research Sources
7 sources cited · 1 strong · 5 moderate · 1 weak
5 Cohorts · 1 Case series · 1 Review
Long-term treatment with recombinant insulin-like growth factor (IGF)-I in children with severe IGF-I deficiency due to growth hormone insensitivity
Journal of Clinical Endocrinology and Metabolism · 2007
Research in a 12-year study of 76 children with severe IGF-I deficiency found that recombinant IGF-I therapy increased height velocity from a baseline of 2.8 cm/year to 8.0 cm/year during the first treatment year, with sustained anabolic effects maintained above baseline for up to 8 years, establishing IGF-I as a primary growth and anabolic mediator.
Early-onset colorectal cancer in Australia: environmental, microbial, and policy implications.
Dig Dis · 2026
# Summary Research found that early-onset colorectal cancer in Australia is associated with multiple environmental and microbial factors, including gut dysbiosis, colibactin-producing bacteria, microplastics, and endocrine-disrupting chemicals, which work through mechanisms such as insulin resistance, chronic inflammation, and IGF-1-mediated signaling to accelerate tumor development in younger adults. This study demonstrated that traditional risk factors alone do not fully explain the recent rise in early-onset cases, suggesting that cumulative environmental exposures and microbial disruptions are primary drivers of the observed birth-cohort effect and disproportionate left-sided tumor predominance.
Speckle-tracking echocardiography reveals the synergistic impact of GH/IGF-1 excess and metabolic dysregulation on cardiac dysfunction in acromegaly.
Pituitary · 2026
# Summary Research found that in acromegaly patients, elevated IGF-1 levels directly drive subclinical cardiac dysfunction, with this effect significantly amplified by concurrent metabolic dysregulation (elevated BMI and triglyceride-glucose levels). This study demonstrated that patients achieving biochemical remission showed improved cardiac structure and function, supporting the use of speckle-tracking echocardiography for early detection and risk stratification of cardiac involvement in this condition.
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Lacticaseibacillus parahuelsenbergensis THGS-36 alleviates acne-like inflammation and lipogenesis in sebocytes via CREB signaling.
Life Sci · 2026
# Primary Finding This study demonstrated that a cell-free supernatant from *Lacticaseibacillus parahuelsenbergnis* THGS-36 reduces acne-related inflammation and sebum production in sebocytes through modulation of CREB signaling, while also exhibiting direct antibacterial activity against *Cutibacterium acnes*. Researchers observed that THGS-36 suppressed inflammatory cytokine secretion and lipogenesis-related gene expression, suggesting multi-target therapeutic potential for acne management.
The biomarkers uCTX-II, CS846 and IGF-1 are associated with clinical and ultrasound scores in haemophilic arthropathy: a cross-sectional study.
Rheumatol Int · 2026
# Summary This study demonstrated that IGF-1 showed a negative correlation with joint damage severity in patients with severe hemophilia, meaning lower IGF-1 levels were associated with greater clinical and ultrasound evidence of joint deterioration. Researchers identified IGF-1 as a candidate biomarker for assessing hemophilic arthropathy severity, alongside uCTX-II and CS846, though they noted that longitudinal studies are needed to confirm its clinical utility.
Pharmacokinetic studies of recombinant human insulin-like growth factor I (rhIGF-I)/rhIGF-binding protein-3 complex administered to patients with growth hormone insensitivity syndrome
Journal of Clinical Endocrinology and Metabolism · 2006
Research in a pharmacokinetic study found that a single subcutaneous injection of rhIGF-I/rhIGFBP-3 complex effectively raised circulating IGF-I levels into the normal range for a sustained 24-hour period in adolescents with growth hormone insensitivity syndrome, demonstrating improved pharmacokinetic profile compared with rhIGF-I alone.
IGF-2-mediated hypoglycemia in a patient with a phyllodes tumor of the breast: a rare presentation of non-islet cell tumor hypoglycemia.
Endocrinol Diabetes Metab Case Rep · 2026
# Summary Research found that a phyllodes tumor of the breast caused non-islet cell tumor hypoglycemia (NICTH) through IGF-2 secretion, demonstrating that an elevated IGF-2:IGF-1 ratio can be a more reliable diagnostic indicator than absolute IGF-2 levels alone. This study highlighted that surgical removal of the tumor resulted in complete resolution of hypoglycemia, confirming both the diagnosis and the effectiveness of tumor resection as definitive treatment for IGF-2-mediated hypoglycemia.
IGF-1 Side Effects & Safety Considerations
Moderate risk profile. Review all reported considerations carefully before use.
Reported contraindications & considerations
Consult a qualified healthcare professional before making any health decisions. This information is educational only and does not constitute medical advice.
Where to Buy IGF-1 — Providers & Availability
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Questions to Ask Your Provider
Frequently Asked Questions — IGF-1
IGF-1 (insulin-like growth factor 1; somatomedin C) is an endogenous 70-amino-acid polypeptide produced primarily in the liver in response to growth hormone signaling, functioning as the principal mediator of GH anabolic effects through its receptor (IGF-1R) expressed in virtually all tissues, with roles in muscle protein synthesis, bone growth, and cellular proliferation. IGF-1 activates IGF-1R tyrosine kinase to stimulate PI3K/Akt and MAPK/ERK signaling cascades, promoting protein synthesis, cell survival, and glucose uptake in muscle and bone; endogenous IGF-1 levels peak during puberty and decline with age, and GH-stimulating interventions exert many of their effects by elevating circulating IGF-1.
muscle growth, Recovery, fat metabolism, tissue repair, GH axis.
Research on IGF-1 primarily documents effects related to muscle growth and Recovery and fat metabolism and tissue repair and GH axis. These are areas covered in preclinical and clinical literature — individual response varies and effects depend on context of use.
Reported contraindications and considerations for IGF-1 include active cancer history, diabetes, pregnant or nursing. This is educational information only — consult a qualified healthcare professional before use.
14 providers in the directory currently offer IGF-1.
Research in a 12-year study of 76 children with severe IGF-I deficiency found that recombinant IGF-I therapy increased height velocity from a baseline of 2.8 cm/year to 8.0 cm/year during the first treatment year, with sustained anabolic effects maintained above baseline for up to 8 years, establishing IGF-I as a primary growth and anabolic mediator.