Follistatin vs Somatropin (HGH)
Side-by-side comparison of key properties, dosing, and research.
Anabolic & IGF
FollistatinGrowth Hormone PeptidesAnti-Aging & Longevity
Somatropin (HGH)- Summary
- Follistatin is an endogenous glycoprotein that acts as a potent inhibitor of myostatin and activin, two proteins that limit muscle growth. By binding and neutralizing myostatin, follistatin removes the primary brake on skeletal muscle hypertrophy, enabling significant muscle growth beyond normal physiological limits. It is distinct from its isoforms Follistatin 315 and Follistatin 344 in tissue distribution and binding affinity.
- Somatropin is recombinant human growth hormone (rhGH), identical in structure to the 191-amino acid pituitary-derived growth hormone. It is FDA-approved for growth hormone deficiency, short stature, and wasting conditions. Off-label, it is widely explored for body composition, anti-aging, and performance enhancement, though significant risks accompany unsupervised use.
- Half-Life
- ~3–5 hours (endogenous form)
- 2-3 hours (subcutaneous); 20-30 minutes (intravenous)
- Admin Route
- IM, SubQ
- Subcutaneous, Intramuscular (less common)
- Research
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- Typical Dose
- 50–100 mcg per injection site
- 0.15-0.3 mg/day (adults); titrated to IGF-1 levels
- Frequency
- Every other day or 2–3x per week
- Once daily
- Key Benefits
- Potent myostatin inhibition enabling supraphysiological muscle growth
- Increases skeletal muscle mass and fiber size
- May accelerate recovery from muscle injury
- Potential benefits in muscular dystrophy and sarcopenia
- Synergistic with IGF-1 and growth hormone in anabolic protocols
- Animal studies show dramatic increases in muscle mass
- Reduces muscle fibrosis in dystrophic models
- Increases lean muscle mass and reduces body fat (particularly visceral)
- Restores growth hormone deficiency (FDA-approved)
- Improves bone mineral density
- Enhances exercise capacity and recovery
- Supports skin thickness and collagen synthesis
- Improves lipid profile in GHD patients
- Explored for anti-aging and cellular regeneration
- Side Effects
- Potential for excessive muscle growth if doses are not controlled
- FSH suppression with implications for fertility in women
- Theoretical risk of cardiac hypertrophy with prolonged high-dose use
- Limited human safety data available
- +1 more
- Fluid retention and edema (common, dose-dependent)
- Carpal tunnel syndrome
- Joint and muscle pain
- Insulin resistance and elevated blood glucose
- +3 more
- Stacks With
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