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ToolsCompareGHK vs HGH Fragment 176-191

GHK vs HGH Fragment 176-191

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

Skin & CosmeticAnti-Aging & Longevity
GHK
Fat Loss & Metabolic
HGH Fragment 176-191
Summary
GHK is the natural tripeptide (Gly-His-Lys) released from human albumin that activates tissue remodeling, collagen synthesis, and anti-aging gene expression. The copper-free form is the biological signaling molecule; it chelates copper in tissue to form GHK-Cu but also has independent biological activity.
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
Extremely short as free peptide; tissue binding extends local effects
~30 minutes
Admin Route
SubQ, Topical, Oral
SubQ
Research
Typical Dose
100–500 mcg
250–500 mcg
Frequency
Daily or 5x per week
1–3 times daily
Key Benefits
  • Stimulates collagen and extracellular matrix synthesis
  • Activates tissue repair gene expression programs
  • Anti-aging: reverses 57% of age-related gene changes
  • Antioxidant and anti-inflammatory
  • Wound healing and skin barrier repair
  • Improves skin laxity, texture, and radiance
  • Neuroprotective (stimulates NGF, BDNF)
  • Anti-fibrotic in liver and lung models
  • 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
  • Excellent safety profile (naturally occurring peptide)
  • Rare: mild injection site reaction (SC)
  • No significant adverse effects identified in research
  • Injection site irritation
  • Temporary lethargy
  • Headache (rare)
  • Nausea (rare)
Stacks With