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ToolsCompareSpermidine vs Tripeptide-29

Spermidine vs Tripeptide-29

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

Anti-Aging & LongevityCognitive Enhancement
Spermidine
Skin & CosmeticAnti-Aging & Longevity
Tripeptide-29
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.
Tripeptide-29 is a pro-collagen cosmetic peptide composed of proline, hydroxyproline, and glycine — the core repeating unit of collagen. Applied topically, it signals dermal fibroblasts that collagen degradation has occurred, triggering compensatory new collagen synthesis.
Half-Life
~30–60 minutes, but gut bacteria produce it continuously; supplementation raises tissue levels over weeks
Not applicable (topical)
Admin Route
Oral
Topical
Research
Typical Dose
1–5 mg
0.01-0.1% in formulation
Frequency
Once daily
Once or twice daily
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
  • Stimulates fibroblast collagen synthesis via damage-signal mechanism
  • Reduces fine lines and improves skin smoothness
  • Supports dermal matrix integrity
  • Naturally bioidentical to collagen fragment sequences
  • Well-tolerated in all skin types
  • Synergistic with copper peptides and retinoids
Side Effects
  • Generally very well tolerated
  • Rare: mild GI discomfort at high doses
  • May temporarily reduce some gut bacteria species
  • Rare: headache at initiation
  • Excellent tolerability profile
  • No documented significant adverse effects at cosmetic concentrations
  • Rare sensitivity reactions in individuals with peptide allergies
Stacks With