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ToolsCompareThymosin Beta-4 vs Spermidine

Thymosin Beta-4 vs Spermidine

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

Recovery & RepairAnti-Aging & Longevity
Thymosin Beta-4
Anti-Aging & LongevityCognitive Enhancement
Spermidine
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.
Spermidine is a naturally occurring polyamine found in all living cells, with exceptionally high concentrations in wheat germ, aged cheese, and human sperm. It is the most studied autophagy-inducing dietary compound, shown to extend lifespan across multiple species and reduce cardiovascular and cognitive aging.
Half-Life
Not well characterized; likely similar to TB-500 (~1–2 hours)
~30–60 minutes, but gut bacteria produce it continuously; supplementation raises tissue levels over weeks
Admin Route
SubQ, IM
Oral
Research
Typical Dose
5–10 mg
1–5 mg
Frequency
2x per week (loading), then 1x per week (maintenance)
Once daily
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
  • Induces autophagy — cellular self-cleaning
  • Extends lifespan in yeast, flies, worms, and mice
  • Reduces cardiovascular aging and arterial stiffness
  • Reduces all-cause mortality (human epidemiological data)
  • Neuroprotective: reduces amyloid and tau pathology
  • Promotes hair growth (anagen phase activation)
  • Reduces age-related immune decline
  • Improves memory in aging models
Side Effects
  • Generally very well tolerated
  • Injection site reactions
  • Mild fatigue at initiation (repair signaling)
  • Rare: mild inflammatory response
  • +1 more
  • Generally very well tolerated
  • Rare: mild GI discomfort at high doses
  • May temporarily reduce some gut bacteria species
  • Rare: headache at initiation
Stacks With