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ToolsCompareSemaglutide vs GHK

Semaglutide vs GHK

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

GLP-1 / Weight Loss Agonists
Semaglutide
Skin & CosmeticAnti-Aging & Longevity
GHK
Summary
Semaglutide is an FDA-approved GLP-1 receptor agonist originally developed for type 2 diabetes that has proven remarkably effective for weight loss. Clinical trials show average 15–20% body weight reduction. It is marketed as Ozempic (diabetes) and Wegovy (weight management).
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.
Half-Life
~7 days
Extremely short as free peptide; tissue binding extends local effects
Admin Route
SubQ, Oral
SubQ, Topical, Oral
Research
Typical Dose
0.25 mg → 0.5 mg → 1 mg → 1.7 mg → 2.4 mg
100–500 mcg
Frequency
Once weekly, subcutaneous
Daily or 5x per week
Key Benefits
  • Average 15–20% body weight reduction in clinical trials (STEP trials)
  • Significant reduction in appetite and food cravings
  • Improvement in blood sugar control and insulin sensitivity
  • Reduces cardiovascular risk (SELECT trial: 20% reduction in MACE)
  • May reduce risk of kidney disease
  • Improves metabolic markers (cholesterol, blood pressure)
  • FDA-approved — extensively studied with robust safety data
  • Weekly dosing convenience
  • 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
Side Effects
  • Nausea (most common, especially during titration)
  • Vomiting
  • Diarrhea or constipation
  • Abdominal discomfort
  • +4 more
  • Excellent safety profile (naturally occurring peptide)
  • Rare: mild injection site reaction (SC)
  • No significant adverse effects identified in research
Stacks With