Peptide Comparison
Tripeptide-29vsGHK-Cu
The minimal collagen-mimetic tripeptide (Gly-Pro-Hyp) that stimulates fibroblast collagen synthesis and resists photoaging.
A naturally occurring copper peptide that acts like a master switch for your body's repair systems—boosting collagen production, accelerating wound healing, and helping your skin rebuild itself from the inside out.
At a Glance
Quick
comparison
Dose Range
Tripeptide-29
0.5%–2% %
GHK-Cu
1–3 mg
Frequency
Tripeptide-29
Once daily
GHK-Cu
Once daily
Administration
Tripeptide-29
Topical
GHK-Cu
Subcutaneous injection
Cycle Length
Tripeptide-29
Ongoing/indefinite
GHK-Cu
8-12 weeks
Onset Speed
Tripeptide-29
Moderate (1-2 weeks)
GHK-Cu
Moderate (1-2 weeks)
Evidence Level
Tripeptide-29
Limited human trials
GHK-Cu
Strong preclinical (extensive animal studies)
Efficacy
Benefit
ratings
Collagen Synthesis
Anti-Photoaging
Skin Hydration
Skin Rejuvenation
Wound Healing
Tissue Regeneration
Technical Data
Compound
specifications
Tripeptide-29
Molecular Formula
C12H19N3O5
Molecular Weight
285.3 Da
Half-Life
Oral: rapidly metabolized to Pro-Hyp; accumulates in skin tissue over hours; topical: sustained local activity
Bioavailability
4.4% absolute oral bioavailability; transporter-mediated intestinal absorption; preferential skin tissue accumulation
CAS Number
2239-67-0
GHK-Cu
Molecular Formula
C14H23N6O4Cu
Molecular Weight
403.93 g/mol
Half-Life
Approximately 1 hour (plasma)
Bioavailability
High when injected subcutaneously; variable topically depending on formulation
CAS Number
49557-75-7
Protocols
Dosing
tiers
Tripeptide-29
GHK-Cu
Applications
Best
suited for
Tripeptide-29
Individuals seeking evidence-based collagen supplementation for skin health
Tripeptide-29 is particularly well-suited for individuals focused on individuals seeking evidence-based collagen supplementation for skin health. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Those with photoaged skin from chronic sun exposure
Tripeptide-29 is particularly well-suited for individuals focused on those with photoaged skin from chronic sun exposure. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
People wanting to support skin hydration and elasticity from both oral and topical routes
Tripeptide-29 is particularly well-suited for individuals focused on people wanting to support skin hydration and elasticity from both oral and topical routes. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
Users looking for a collagen-mimetic peptide with clinical trial data supporting efficacy
Tripeptide-29 is particularly well-suited for individuals focused on users looking for a collagen-mimetic peptide with clinical trial data supporting efficacy. Research and clinical experience suggest meaningful benefits in this area when used as part of a comprehensive treatment approach.
GHK-Cu
Anti-Aging Warriors
If fine lines, sagging skin, and lost elasticity are your enemies, GHK-Cu is your secret weapon. It ramps up collagen and elastin production—the two proteins responsible for keeping your skin firm and youthful. Studies show it can tighten loose skin and improve elasticity better than many popular skincare ingredients.
Wound Healing Champions
Whether you're recovering from surgery, dealing with stubborn wounds, or healing from a cosmetic procedure, GHK-Cu accelerates the entire repair process. It attracts immune cells, builds new blood vessels, and stimulates the growth factors your body needs to rebuild tissue faster and better.
Scar Reducers
GHK-Cu doesn't just heal wounds—it helps remodel scar tissue. By regulating how your body lays down collagen during healing, it can help scars become flatter, softer, and more like surrounding normal skin. It even reduces the TGF-beta signals that lead to thick, raised scars.
Hair Growth Seekers
Research shows GHK-Cu can enlarge hair follicles and activate the Wnt/beta-catenin pathway—the signaling system that tells hair follicles to grow. If you're noticing thinning hair or increased shedding, this peptide may help stimulate thicker, healthier growth over time.
Safety Profile
Side
effects
Tripeptide-29
Common
- Mild Gastrointestinal Adjustment
- Aftertaste (oral)
- Mild Skin Warmth (topical)
- Initial Skin Purging
Uncommon
- Allergic Sensitivity
Serious
- Anaphylaxis (theoretical)
- Limited Bioavailability and Potential Immunogenicity
GHK-Cu
Common
- Injection site redness
- Skin tingling (topical use)
- Minor bruising
- Mild swelling at injection site
Uncommon
- Mild headache
- Temporary skin purging (topical)
Serious
- Allergic reaction
Research Status
Safety
& evidence
Tripeptide-29
Evidence Level
Limited human trials
FDA Status
Research compound
Safety Overview
Tripeptide-29 (Gly-Pro-Hyp, glycyl-prolyl-hydroxyproline) is a naturally occurring collagen-derived tripeptide with an excellent cosmetic safety profile. This is the fundamental repeat unit of collagen protein, making it highly biocompatible. Both oral and topical forms demonstrate minimal adverse effects in clinical trials. No serious adverse events have been reported in published clinical studies spanning over 15 years. The tripeptide is generally recognized as safe (GRAS) for both topical and oral use by regulatory authorities. Individual responses are generally benign and limited to mild gastrointestinal adjustment with oral supplementation or transient dermal warmth with topical application. The primary safety consideration is allergenicity in individuals with gelatin or collagen allergies, which is rare but requires awareness. Molecular weight (285.3 Da) ensures limited systemic absorption when applied topically.
Contraindications
- xKnown allergy to collagen, gelatin, or animal-derived protein products
- xActive skin infections or dermatitis at the topical application site
- xHypersensitivity to hydroxyproline-containing peptides
- xConcurrent use with products at extreme pH that may hydrolyze the peptide
GHK-Cu
Evidence Level
Strong preclinical (extensive animal studies)
FDA Status
Research compound
Safety Overview
GHK-Cu has an excellent safety profile backed by decades of research since its discovery in the 1970s. It's a naturally occurring peptide found in your blood, saliva, and urine—your body already knows it well. Concentrations naturally decline with age (from about 200 ng/mL at age 20 to 80 ng/mL by age 60), which is part of why supplementation makes sense. Most side effects are mild and injection-related. The copper component is well-tolerated at recommended doses but should be monitored in long-term use.
Contraindications
- xWilson's disease or copper metabolism disorders
- xKnown allergy to copper or peptide components
- xActive cancer or history of cancer
- xPregnancy or breastfeeding
- xChildren and adolescents
Decision Guide
Which is
right for you?
Choose Tripeptide-29 if...
- Individuals seeking evidence-based collagen supplementation for skin health
- Those with photoaged skin from chronic sun exposure
- People wanting to support skin hydration and elasticity from both oral and topical routes
- Users looking for a collagen-mimetic peptide with clinical trial data supporting efficacy
Choose GHK-Cu if...
- Skin rejuvenation and anti-aging
- Wound and injury recovery
- Scar reduction
- Hair growth support