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ToolsComparePalmitoyl Dipeptide-6 vs HGH Fragment 176-191

Palmitoyl Dipeptide-6 vs HGH Fragment 176-191

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

Skin & CosmeticAnti-Aging & Longevity
Palmitoyl Dipeptide-6
Fat Loss & Metabolic
HGH Fragment 176-191
Summary
Palmitoyl Dipeptide-6 is a synthetic dipeptide (lysine-threonine) with a palmitoyl fatty acid tail, designed to penetrate the skin barrier and stimulate the extracellular matrix components essential for skin firmness. It activates fibronectin and type IV collagen synthesis, improving skin density and firmness particularly in mature or sagging skin.
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
Not applicable (topical)
~30 minutes
Admin Route
Topical
SubQ
Research
Typical Dose
0.005–0.05% in formulation
250–500 mcg
Frequency
Once or twice daily
1–3 times daily
Key Benefits
  • Increases skin firmness and density
  • Stimulates fibronectin and collagen IV production
  • Strengthens the dermal-epidermal junction
  • Reduces skin sagging in mature skin
  • Improves skin texture and smoothness
  • Supports extracellular matrix integrity
  • 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
  • Generally well-tolerated
  • Rare mild skin irritation in sensitive individuals
  • No known systemic effects at cosmetic concentrations
  • Injection site irritation
  • Temporary lethargy
  • Headache (rare)
  • Nausea (rare)
Stacks With