Thymosin Beta-4 vs Follistatin
Side-by-side comparison of key properties, dosing, and research.
Recovery & RepairAnti-Aging & Longevity
Thymosin Beta-4Anabolic & IGF
Follistatin- Summary
- Thymosin Beta-4 is an endogenous 43-amino acid peptide that is the primary intracellular actin sequestering peptide. It promotes tissue repair, reduces inflammation, regenerates hair follicles, and protects cardiac tissue. Closely related to TB-500 (the active fragment), it is used for systemic tissue recovery and anti-aging.
- 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.
- Half-Life
- Not well characterized; likely similar to TB-500 (~1–2 hours)
- ~3–5 hours (endogenous form)
- Admin Route
- SubQ, IM
- IM, SubQ
- Research
- —
- —
- Typical Dose
- 5–10 mg
- 50–100 mcg per injection site
- Frequency
- 2x per week (loading), then 1x per week (maintenance)
- Every other day or 2–3x per week
- Key Benefits
- Systemic tissue repair and regeneration
- Promotes cardiac recovery after myocardial infarction
- Hair follicle regeneration and anti-hair-loss
- Anti-inflammatory (systemic)
- Wound healing acceleration
- Neuroprotection after brain injury
- Protects against ischemia-reperfusion injury
- Anti-aging at cellular level
- Synergizes powerfully with BPC-157
- 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
- Side Effects
- Generally very well tolerated
- Injection site reactions
- Mild fatigue at initiation (repair signaling)
- Rare: mild inflammatory response
- +1 more
- 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
- Stacks With
- —
- —