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ToolsCompareFollistatin 315 vs NAD+

Follistatin 315 vs NAD+

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

Anabolic & IGF
Follistatin 315
Anti-Aging & Longevity
NAD+
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.
NAD+ (Nicotinamide Adenine Dinucleotide) is a coenzyme found in all living cells that declines dramatically with age. It is critical for energy metabolism, DNA repair, and sirtuin activation. IV and subcutaneous NAD+ supplementation is used in anti-aging protocols and addiction recovery programs.
Half-Life
~3–5 hours (longer systemic circulation vs FST-344)
Varies by route; IV provides direct cellular delivery
Admin Route
SubQ, IM
IV, SubQ, Oral
Research
Typical Dose
No established human dosing protocol
500–1000 mg
Frequency
Research use only
Daily for 4–10 days (loading), then monthly maintenance
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
  • Restored cellular energy production (ATP)
  • Sirtuin activation for longevity and metabolic regulation
  • Enhanced DNA repair capacity
  • Improved mitochondrial function and biogenesis
  • Cognitive clarity and mental energy
  • Reduced inflammation
  • Addiction withdrawal support (opioids, alcohol, benzodiazepines)
  • Improved sleep quality
  • Enhanced athletic endurance
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
  • Flushing and warmth during IV infusion
  • Nausea during rapid IV administration
  • Chest tightness (from rapid infusion — slow the rate)
  • Injection site irritation (subcutaneous)
  • +1 more
Stacks With