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ToolsCompareSpermidine vs LL-37

Spermidine vs LL-37

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

Anti-Aging & LongevityCognitive Enhancement
Spermidine
Immune SupportRecovery & Repair
LL-37
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.
LL-37 is the only known human cathelicidin antimicrobial peptide. It kills bacteria, fungi, and viruses by disrupting their membranes, while simultaneously modulating immune responses. Used for antimicrobial protection, immune priming, and wound healing.
Half-Life
~30–60 minutes, but gut bacteria produce it continuously; supplementation raises tissue levels over weeks
Very short (~1–2 hours) in plasma due to protease degradation; topical use bypasses systemic clearance
Admin Route
Oral
SubQ, Topical, Intranasal
Research
Typical Dose
1–5 mg
100–300 mcg
Frequency
Once daily
2–3x per week
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
  • Broad-spectrum antimicrobial (bacteria, fungi, viruses)
  • Promotes wound healing and angiogenesis
  • Immune system modulation — enhances innate immunity
  • Reduces LPS-mediated endotoxemia
  • Anti-biofilm activity against resistant organisms
  • Promotes tissue regeneration and keratinocyte migration
  • May protect against sepsis
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 redness and irritation
  • Mild inflammatory response at injection site
  • Potential pro-inflammatory at high doses
  • Rare: fever or flu-like symptoms at initiation
Stacks With