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ToolsCompareFollistatin 315 vs Carnosine

Follistatin 315 vs Carnosine

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

Anabolic & IGF
Follistatin 315
Anti-Aging & LongevityRecovery & Repair
Carnosine
Summary
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.
Carnosine is an endogenous dipeptide (beta-alanine + histidine) found in high concentrations in muscle and brain. It is a potent anti-aging molecule with broad spectrum antioxidant, anti-glycation, anti-carbonylation, and metal chelating properties, making it one of the most protective naturally occurring dipeptides.
Half-Life
~3–5 hours (longer systemic circulation vs FST-344)
~1.5 minutes (rapidly hydrolyzed to beta-alanine and histidine by carnosinase in blood; tissue levels maintained via constant synthesis)
Admin Route
SubQ, IM
Oral, Topical
Research
Typical Dose
No established human dosing protocol
1,000–2,000 mg
Frequency
Research use only
Once to twice daily with meals
Key Benefits
  • 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
  • Potent anti-glycation (prevents protein cross-linking/aging)
  • Broad-spectrum antioxidant in muscle and brain
  • Extends cell lifespan and protects telomeres
  • Improves muscle performance and delays fatigue (pH buffering)
  • Neuroprotective against Alzheimer's amyloid-beta
  • Wound healing acceleration
  • Anti-cataract properties (eye health)
  • Improves diabetes complications via AGE prevention
  • Chelates excess copper and zinc
Side Effects
  • 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
  • Very well tolerated
  • Rare: mild GI discomfort at high doses
  • No significant adverse effects in human studies
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