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ToolsCompareMatrixyl vs HGH Fragment 176-191

Matrixyl vs HGH Fragment 176-191

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

Skin & Cosmetic
Matrixyl
Fat Loss & Metabolic
HGH Fragment 176-191
Summary
Matrixyl is the most widely used collagen-stimulating cosmetic peptide. As a matrikine — a fragment of type I procollagen — it signals skin cells to synthesize new collagen, elastin, and fibronectin, reducing wrinkle depth and improving skin firmness and elasticity.
HGH Fragment 176-191 (also known as AOD-9604) is a stabilized, modified fragment of the human growth hormone molecule corresponding to amino acids 176–191 with an addition of a tyrosine residue at the N-terminus. It retains HGH's fat-burning properties without the anabolic, diabetogenic, or IGF-1-stimulating effects.
Half-Life
N/A — topical; sustained signaling effects on fibroblasts persist beyond single application
~30 minutes
Admin Route
Topical
SubQ
Research
Typical Dose
3–8% concentration
250–500 mcg
Frequency
Once or twice daily
1–3 times daily
Key Benefits
  • Stimulates collagen I, III, and IV synthesis
  • Increases fibronectin and glycosaminoglycan production
  • Reduces wrinkle depth and length by 27–68% (studies)
  • Improves skin firmness and elasticity
  • Reduces dark circles and undereye bags
  • Synergistic with retinol, vitamin C, and growth factors
  • Suitable for all skin types including sensitive
  • Well-studied with published clinical data
  • Selective fat burning without anabolic side effects
  • Reduces visceral and subcutaneous fat
  • No insulin resistance or blood glucose disruption
  • Does not stimulate IGF-1
  • May support cartilage and bone repair (at higher doses)
  • No effect on growth or organ size
Side Effects
  • Exceptional safety profile
  • Non-irritating, suitable for sensitive skin
  • No known adverse effects at cosmetic concentrations
  • Injection site irritation
  • Temporary lethargy
  • Headache (rare)
  • Nausea (rare)
Stacks With