Spermidine vs Thymulin
Side-by-side comparison of key properties, dosing, and research.
Anti-Aging & LongevityCognitive Enhancement
SpermidineImmune Support
Thymulin- Summary
- 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.
- Thymulin is a nonapeptide hormone produced exclusively by the thymic epithelium. It requires zinc for biological activity and plays a critical role in T-lymphocyte maturation, differentiation, and immune regulation. Thymulin levels decline dramatically with age, contributing to immunosenescence.
- Half-Life
- ~30–60 minutes, but gut bacteria produce it continuously; supplementation raises tissue levels over weeks
- ~30 minutes active half-life
- Admin Route
- Oral
- SubQ
- Research
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- Typical Dose
- 1–5 mg
- 20-30 mcg
- Frequency
- Once daily
- 10 days per month (Khavinson protocol)
- Key Benefits
- 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
- Enhances T-cell maturation and differentiation
- Boosts NK cell cytotoxic activity
- Reduces inflammatory cytokine production (TNF-α, IL-1)
- Anti-nociceptive (pain-reducing) properties
- Restores age-related immune decline
- Anti-inflammatory via serotonin pathway modulation
- Side Effects
- Generally very well tolerated
- Rare: mild GI discomfort at high doses
- May temporarily reduce some gut bacteria species
- Rare: headache at initiation
- Injection site reactions
- Mild fatigue initially as immune system activates
- Stacks With
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