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ToolsCompareMGF (Mechano Growth Factor) vs Retatrutide

MGF (Mechano Growth Factor) vs Retatrutide

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

Anabolic & IGF
MGF (Mechano Growth Factor)
GLP-1 / Weight Loss Agonists
Retatrutide
Summary
MGF (Mechano Growth Factor) is a splice variant of IGF-1 that is locally produced in muscle tissue in response to mechanical damage from exercise. It activates muscle satellite cells (stem cells) to proliferate and repair damaged fibers, making it specifically targeted at exercise-induced hypertrophy.
Retatrutide is an investigational triple receptor agonist targeting GLP-1, GIP, and glucagon receptors simultaneously. Phase 2 trials showed an unprecedented average 24% body weight reduction at 48 weeks — exceeding any approved medication to date. It is in Phase 3 trials as of 2024.
Half-Life
Native MGF: minutes. PEG-MGF: ~3 days
~10–12 days
Admin Route
SubQ, IM
SubQ
Research
Typical Dose
200–400 mcg
0.5 mg → 1 mg → 2 mg → 4 mg → 8 mg → 12 mg
Frequency
1–2 times per week
Once weekly
Key Benefits
  • Activates muscle satellite cells for repair and growth
  • Accelerates recovery from muscle damage
  • Synergistic with IGF-1 LR3 (different mechanisms)
  • Promotes muscle hypertrophy specifically at exercised muscles
  • Faster recovery between training sessions
  • Potential for injury repair in connective tissue
  • ~24% body weight reduction at 48 weeks in Phase 2 (highest dose)
  • Superior to both semaglutide and tirzepatide in early trial comparisons
  • Triple receptor mechanism addresses multiple obesity pathways
  • Significant reduction in liver fat (MASH/NAFLD indication being studied)
  • Improved cardiovascular and metabolic markers
  • Once-weekly dosing
  • Potential for greatest weight loss of any currently investigated compound
Side Effects
  • Muscle soreness (satellite cell activation)
  • Injection site irritation
  • Hypoglycemia risk (modest, less than IGF-1 LR3)
  • Nausea and vomiting (common during titration, similar to semaglutide/tirzepatide)
  • Diarrhea
  • Constipation
  • Heart rate increase (from glucagon receptor agonism)
  • +2 more
Stacks With