Testagen vs Spermidine
Side-by-side comparison of key properties, dosing, and research.
Anti-Aging & Longevity
TestagenAnti-Aging & LongevityCognitive Enhancement
Spermidine- Summary
- Testagen is a tetrapeptide bioregulator (Lys-Glu-Asp-Gly) developed by Professor Vladimir Khavinson, tissue-specific for the testes. It supports Leydig cell function, normalization of testosterone biosynthesis, and spermatogenic activity. Testagen is used in men's health protocols for age-related testosterone decline, male fertility support, and testicular 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
- Short (minutes); sustained gene-regulatory effects
- ~30–60 minutes, but gut bacteria produce it continuously; supplementation raises tissue levels over weeks
- Admin Route
- SubQ, Oral
- Oral
- Research
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- Typical Dose
- 10 mg per day
- 1–5 mg
- Frequency
- Daily for 10–30 days
- Once daily
- Key Benefits
- Supports endogenous testosterone synthesis via Leydig cell normalization
- Promotes spermatogenesis and sperm quality
- Anti-aging effects on testicular tissue
- May attenuate age-related testosterone decline
- Mechanistically distinct from TRT — does not suppress HPG axis
- Useful adjunct to Gonadorelin and Kisspeptin-10 in male hormonal protocols
- Supports male fertility without exogenous hormone replacement
- 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 well tolerated
- Mild injection site reactions
- No significant endocrine disruption reported at standard doses
- Generally very well tolerated
- Rare: mild GI discomfort at high doses
- May temporarily reduce some gut bacteria species
- Rare: headache at initiation
- Stacks With
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