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ToolsCompareThymosin Alpha-1 vs Spermidine

Thymosin Alpha-1 vs Spermidine

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

Immune SupportAnti-Aging & Longevity
Thymosin Alpha-1
Anti-Aging & LongevityCognitive Enhancement
Spermidine
Summary
Thymosin Alpha-1 is a naturally occurring 28-amino acid peptide derived from the thymus gland. It is a powerful immune modulator approved in many countries for treating chronic hepatitis B, hepatitis C, and as an adjunct in cancer immunotherapy.
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
2–3 hours
~30–60 minutes, but gut bacteria produce it continuously; supplementation raises tissue levels over weeks
Admin Route
SubQ
Oral
Research
Typical Dose
0.8–1.6 mg
1–5 mg
Frequency
Twice weekly
Once daily
Key Benefits
  • Enhances T-cell and NK cell activity
  • Supports recovery from viral and bacterial infections
  • May reduce inflammation systemically
  • Supports healthy aging and immune resilience
  • Improves vaccine response
  • Supports liver health
  • May help with chronic fatigue syndrome and post-viral conditions
  • Approved in multiple countries for hepatitis B and C treatment
  • 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
  • Injection site irritation
  • Mild flu-like symptoms initially (immune activation)
  • Fatigue (rare)
  • Generally very well tolerated
  • Rare: mild GI discomfort at high doses
  • May temporarily reduce some gut bacteria species
  • Rare: headache at initiation
Stacks With