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ToolsCompareSpermidine vs Hexarelin

Spermidine vs Hexarelin

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

Anti-Aging & LongevityCognitive Enhancement
Spermidine
Growth Hormone Peptides
Hexarelin
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.
Hexarelin is a potent synthetic GHRP and the strongest GH secretagogue in its class per unit dose. It also exhibits unique cardioprotective properties through direct binding to cardiac CD36 receptors, independent of GH release. Its potency is balanced by a tendency to desensitize GH release with prolonged use, making cycling important.
Half-Life
~30–60 minutes, but gut bacteria produce it continuously; supplementation raises tissue levels over weeks
~70 minutes
Admin Route
Oral
SubQ
Research
Typical Dose
1–5 mg
100–200 mcg
Frequency
Once daily
2–3 times 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
  • Strongest GH pulse per mcg among GHRPs
  • Unique direct cardioprotective effects via CD36
  • Increased IGF-1 and muscle anabolism
  • Accelerated recovery from training
  • Bone density support
  • Anti-aging via GH axis
  • Potential cardiac rehabilitation benefits
Side Effects
  • Generally very well tolerated
  • Rare: mild GI discomfort at high doses
  • May temporarily reduce some gut bacteria species
  • Rare: headache at initiation
  • Water retention
  • Elevated cortisol
  • Elevated prolactin (more pronounced than other GHRPs)
  • Receptor desensitization with continuous use
  • +1 more
Stacks With