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ToolsCompareHGH Fragment 176-191 vs SS-31 (Elamipretide)

HGH Fragment 176-191 vs SS-31 (Elamipretide)

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

Fat Loss & Metabolic
HGH Fragment 176-191
Anti-Aging & Longevity
SS-31 (Elamipretide)
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.
SS-31 (Elamipretide) is a synthetic mitochondria-targeting tetrapeptide that concentrates in the inner mitochondrial membrane and protects cardiolipin from oxidative damage. It is one of the most promising mitochondrial longevity compounds, studied in clinical trials for heart failure, renal disease, and age-associated mitochondrial dysfunction.
Half-Life
~30 minutes
~2–5 hours
Admin Route
SubQ
SubQ
Research
Typical Dose
250–500 mcg
5–10 mg
Frequency
1–3 times daily
Daily to several times per week
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
  • Restores mitochondrial function and ATP production
  • Protects inner mitochondrial membrane cardiolipin
  • Reduces mitochondrial reactive oxygen species (ROS)
  • Improves exercise capacity and reduces fatigue
  • Cardioprotective — studied in heart failure trials
  • Renoprotective — reduces ischemic kidney injury
  • Anti-aging via mitochondrial preservation
  • Potential in neurodegenerative disease prevention
Side Effects
  • Injection site irritation
  • Temporary lethargy
  • Headache (rare)
  • Nausea (rare)
  • Injection site irritation
  • Nausea (rare)
  • Generally well-tolerated in clinical trials
Stacks With