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ToolsCompareEpithalon vs Follistatin 315

Epithalon vs Follistatin 315

Side-by-side comparison of key properties, dosing, and research.

Anti-Aging & Longevity
Epithalon
Anabolic & IGF
Follistatin 315
Summary
Epithalon is a synthetic tetrapeptide developed from the pineal gland extract Epithalamin by Russian scientist Dr. Vladimir Khavinson. It is one of the most researched longevity peptides, known for activating telomerase and extending telomere length — the molecular hallmarks of cellular aging.
Follistatin 315 is a splice variant isoform of follistatin produced by alternative mRNA processing. Unlike Follistatin 344 which is tethered to cell surfaces via heparan sulfate proteoglycans, FST-315 circulates freely in the bloodstream and has broader systemic distribution. It is the predominant circulating form and exerts systemic myostatin inhibition as well as FSH suppression, making it relevant to both muscle growth and reproductive endocrinology.
Half-Life
2–4 hours
~3–5 hours (longer systemic circulation vs FST-344)
Admin Route
SubQ, Sublingual
SubQ, IM
Research
Typical Dose
5–10 mg total per cycle
No established human dosing protocol
Frequency
0.5–1 mg daily
Research use only
Key Benefits
  • Activates telomerase enzyme, extending telomere length
  • May slow cellular and biological aging
  • Regulates melatonin production and circadian rhythms
  • Improves sleep quality
  • Powerful antioxidant properties
  • May reduce incidence of age-related diseases
  • Supports immune system function
  • Studied for cancer prevention properties in animal models
  • Systemic myostatin inhibition for whole-body muscle growth
  • Freely circulating — broader tissue distribution than FST-344
  • Strong FSH-suppressive activity useful in certain hormonal protocols
  • Potential for greater anabolic effect across multiple muscle groups simultaneously
  • May be more relevant to reproductive endocrinology applications
  • Studied in gene therapy approaches for muscular dystrophy
Side Effects
  • Injection site irritation (mild)
  • Temporary sleep changes during cycle (usually improves)
  • Rare: fatigue
  • Systemic FSH suppression — significant concern for fertility
  • Greater potential for off-target effects vs FST-344 due to systemic distribution
  • Limited human safety data
  • Potential cardiac hypertrophy with prolonged high-dose exposure
Stacks With