Human Growth Hormone (HGH) vs IGF-1 LR3 vs PEG-MGF
A three-way comparison to help you find the right peptide for your research goals.
Human Growth Hormone (HGH)
Human Growth Hormone (somatropin) is a 191-amino acid protein identical to naturally produced GH. FDA-approved for growth hormone deficiency, Turner syndrome, and other conditions. Widely used off-label for anti-aging and performance.
Full details →IGF-1 LR3
IGF-1 LR3 (Long R3 Insulin-like Growth Factor-1) is a modified version of IGF-1 with extended half-life and enhanced potency. The modifications prevent binding to IGF binding proteins, increasing bioavailability.
Full details →PEG-MGF
PEG-MGF (PEGylated Mechano Growth Factor) is a variant of IGF-1 that is produced in response to muscle damage. PEGylation extends its half-life from minutes to several hours, making it practical for use.
Full details →Side-by-Side Comparison
| Aspect | Human Growth Hormone (HGH) | IGF-1 LR3 | PEG-MGF |
|---|---|---|---|
| Mechanism | Binds to GH receptors throughout the body, stimulating IGF-1 production in the liver. Promotes protein synthesis, fat metabolism, and cellular regeneration across multiple tissues. | Binds to IGF-1 receptors to promote protein synthesis, muscle growth, and fat metabolism. The LR3 modification (13 amino acid extension and arginine substitution) extends half-life from minutes to 20-30 hours. | Activates muscle satellite cells (stem cells) and promotes their fusion to existing muscle fibers for repair and growth. MGF is produced naturally in response to mechanical stress on muscles. |
| Typical Dosage | Medical: 0.1-0.3mg/kg/week divided into daily doses. Anti-aging: 1-2 IU daily. Performance: 2-6 IU daily, sometimes higher. | Research protocols typically use 20-100mcg daily, often divided into multiple injections or administered bilaterally to target muscles. | Research protocols typically use 200-400mcg injected into targeted muscle groups 2-3 times weekly, usually post-workout. |
| Administration | Subcutaneous injection, preferably at night to mimic natural pulsatile release. Rotate injection sites. Store refrigerated. | Intramuscular injection (site-specific growth) or subcutaneous for systemic effects. Often cycled 4-6 weeks on, equal time off. | Intramuscular injection, ideally into muscles trained that day. Best administered post-workout when satellite cell activation is relevant. |
| Side Effects | Joint pain, water retention, carpal tunnel syndrome, potential insulin resistance, and acromegaly features with long-term high doses. | Hypoglycemia, joint pain, water retention, potential jaw/hand growth with extended use, and injection site reactions. | Injection site soreness, potential hypoglycemia, and localized swelling. Generally well-tolerated. |
| Best For |
What They Have in Common
Human Growth Hormone (HGH), IGF-1 LR3, PEG-MGF are all commonly used for:
Key Differences
Unique to Human Growth Hormone (HGH):
Unique to IGF-1 LR3:
Detailed Analysis
Commonalities
Both Human Growth Hormone (HGH) and IGF-1 LR3 are commonly used for Muscle Growth, Fat Loss, Recovery & Healing.
Which Should You Choose?
Human Growth Hormone (HGH) has stronger evidence for Fat Loss, Recovery & Healing.
Commonalities
Both Human Growth Hormone (HGH) and PEG-MGF are commonly used for Muscle Growth, Recovery & Healing.
Which Should You Choose?
Human Growth Hormone (HGH) has stronger evidence for Muscle Growth, Recovery & Healing.
Commonalities
Both IGF-1 LR3 and PEG-MGF are commonly used for Muscle Growth, Recovery & Healing.
Which Should You Choose?
IGF-1 LR3 has stronger evidence for Muscle Growth.