Informational only. Not medical advice.INFORMATIONAL PLATFORM ONLY — NOT MEDICAL ADVICE, DIAGNOSIS, OR TREATMENT
Informational only. Not medical advice.INFORMATIONAL PLATFORM ONLY — NOT MEDICAL ADVICE, DIAGNOSIS, OR TREATMENT
Head-to-head comparison of IGF-1 (Insulin-like Growth Factor 1) and IGF-1 LR3 — mechanism, side effects, legal status, and pricing.
Insulin-like Growth Factor 1, a 70-amino-acid peptide hormone that mediates many of growth hormone's anabolic effects. Recombinant IGF-1 (mecasermin) is FDA-approved for severe primary IGF-1 deficiency; non-prescription 'research' use for muscle growth is off-label and unproven.
IGF-1 LR3 is an 83-amino-acid modified IGF-1 analog with a 13-residue N-terminal extension (MFPAMPLSSLFVN) and an Arg-3 substitution. These modifications reduce binding to IGF binding proteins (IGFBPs), extending effective half-life and increasing tissue bioavailability relative to native IGF-1. It is a research/cell-culture reagent and is NOT FDA-approved for any human use. Do not confuse with mecasermin (Increlex), which is recombinant human IGF-1 and IS FDA-approved for severe primary IGF-1 deficiency.
IGF-1 (Insulin-like Growth Factor 1)
IGF-1 LR3
Category
Legal Status
Mechanism
Half-life
Side Effects
COA-verified vendors · trust score ≥70 required · single-vial price — bulk/bundle deals may be lower
IGF-1 (Insulin-like Growth Factor 1)
No pricing data yet.
Check IGF-1 (Insulin-like Growth Factor 1) prices →IGF-1 LR3
COA corpus from Disclosed Labs — independently tested batches only.
IGF-1 (Insulin-like Growth Factor 1)
1
COAs
—
Avg purity
1
Labs
IGF-1 LR3
42
COAs
98.7%
Avg purity
9
Labs
Strong endocrinology literature for deficiency states; performance/anti-aging use in healthy adults is not supported by controlled human trials and carries growth-signaling risk.
Francis et al. (J Mol Endocrinol 1992; PMID 1378742) characterized LR3-IGF-1 as a fusion analog whose enhanced biological potency derives from reduced IGFBP binding; in IGFBP-free cell systems LR3 was actually LESS potent than native IGF-1, underscoring that the 'potency' is really reduced sequestration rather than intrinsically stronger receptor activation. Tomas (Growth Horm IGF Res 2001; PMID 11472075) infused LR(3)IGF-I into food-restricted rats and found it preserved body weight and nitrogen retention but did NOT conserve skeletal muscle protein — which contradicts the common 'potent muscle builder' framing from preclinical literature alone. There are no controlled human trials supporting bodybuilding use. Epidemiologic and mechanistic work reviewed by Grimberg (Cancer Biol Ther 2003; PMID 14688466) links elevated IGF-1 axis activity to breast, prostate, and colorectal cancer risk, so chronic systemic LR3 exposure carries a concrete — not merely theoretical — tumorigenesis concern. IGF-1 and its analogs are banned at all times under the WADA Code.
Key references
IGF-1 (Insulin-like Growth Factor 1) and IGF-1 LR3 are both in the Performance category and may have overlapping mechanisms. Researchers should review both profiles carefully, understand the mechanisms of action, and monitor the relevant biomarkers when combining compounds in the same class. As always, consult a licensed healthcare provider before making any decisions about combining research compounds.
This platform provides informational tools only, not medical advice. This comparison is for educational purposes only. Consult a licensed provider.
Contraindications
Lab Testing
Disclosed Labs