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ToolsCompareSelank vs Spermidine

Selank vs Spermidine

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

Cognitive Enhancement
Selank
Anti-Aging & LongevityCognitive Enhancement
Spermidine
Summary
Selank is a synthetic heptapeptide analog of tuftsin developed in Russia. It is a potent anxiolytic that reduces anxiety and enhances cognitive function without sedation or addiction. It is approved for clinical use in Russia for anxiety disorders.
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
Minutes (but effects persist for hours)
~30–60 minutes, but gut bacteria produce it continuously; supplementation raises tissue levels over weeks
Admin Route
SubQ, Intranasal
Oral
Research
Typical Dose
250–500 mcg
1–5 mg
Frequency
1–3 times daily
Once daily
Key Benefits
  • Reduces anxiety without sedation
  • Enhances memory and learning
  • Improves focus and concentration
  • Stabilizes mood
  • Reduces physiological stress response
  • May enhance motivation
  • No addiction potential or withdrawal
  • Fast-acting — effects within 20–30 minutes
  • Approved clinically in Russia for anxiety disorders
  • 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
  • Mild sedation at higher doses (paradoxical)
  • Fatigue (rare)
  • Irritability during discontinuation (uncommon)
  • Generally very well tolerated
  • Rare: mild GI discomfort at high doses
  • May temporarily reduce some gut bacteria species
  • Rare: headache at initiation
Stacks With