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ToolsCompareHGH Fragment 176-191 vs Syn-Coll

HGH Fragment 176-191 vs Syn-Coll

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

Fat Loss & Metabolic
HGH Fragment 176-191
Skin & CosmeticAnti-Aging & Longevity
Syn-Coll
Summary
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.
Syn-Coll is a palmitoylated tripeptide (Palmitoyl Tripeptide-5) that mimics thrombospondin-1 to activate TGF-beta, the primary growth factor driving collagen synthesis in the dermis. It is one of the most mechanistically direct collagen-stimulating peptides in cosmetic formulations.
Half-Life
~30 minutes
Extended (lipid depot in stratum corneum)
Admin Route
SubQ
Topical
Research
Typical Dose
250–500 mcg
0.005-0.05% in formulation
Frequency
1–3 times daily
Once or twice daily
Key Benefits
  • 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
  • Directly activates TGF-beta for potent collagen synthesis stimulation
  • Increases dermal thickness and firmness
  • Reduces depth of wrinkles and fine lines
  • Improves skin elasticity
  • Clinically validated in collagen induction studies
  • Complementary to retinoids or vitamin C
Side Effects
  • Injection site irritation
  • Temporary lethargy
  • Headache (rare)
  • Nausea (rare)
  • Generally well-tolerated
  • Rare mild irritation at high concentrations
  • Possible sensitivity in individuals with inflammatory skin conditions
Stacks With