Comparison
Fisetin vs GHK-Cu
Side-by-side of Fisetin and GHK-Cu. Every row below is pulled from the compound schema and will update as our data grows. For deeper reads, follow through to each compound page.
Fisetin
Fisetin is a flavonoid found in strawberries with senolytic activity in mouse models. Hickson 2019 confirmed senescent-cell clearance in human adipose tissue.
GHK-Cu
GHK-Cu peptide (glycyl-L-histidyl-L-lysine copper) is a topical copper peptide. Trials show fine-line and wound-healing gains; injectable longevity claims rem.
Effects at a glance
Fisetin
- •Flavonoid found in strawberries; most potent natural senolytic in screening assays (Yousefzadeh 2018)
- •Hickson 2019 confirmed reduced senescent-cell burden in human adipose tissue at 20 mg/kg pulsed for 2 days
- •Pulsed Mayo protocol (20 mg/kg/day x 2 days monthly) is the only dose with human biomarker evidence
- •Daily low-dose (100-500 mg) is mechanistically weaker but commonly used
- •Low oral bioavailability; with-fat dosing modestly improves absorption
- •Active cancer is a relative contraindication pending clearer polyphenol-treatment data
GHK-Cu
- •Endogenous tripeptide that binds copper(II); plasma levels decline ~60% from age 20 to 60
- •Topical RCTs show improvement in skin firmness, fine lines, and barrier function over 12 weeks
- •Wound-healing models report accelerated re-epithelialization in diabetic and aged skin
- •Pickart gene-expression analyses show reset of >4000 genes toward a younger expression profile in cell culture
- •Anecdotal subcutaneous longevity protocols use 1 to 3 mg daily; no human longevity RCTs exist
- •Hair-growth claims rest on small open-label trials and topical scalp formulations
Side-by-side
| Attribute | Fisetin | GHK-Cu |
|---|---|---|
| Category | supplement | peptide |
| Also known as | 3,7,3',4'-tetrahydroxyflavone | Copper Peptide, Glycyl-L-histidyl-L-lysine copper, GHK |
| Half-life (hr) ↗ | 2 | 0.5 |
| Typical dose (mg) ↗ | 500 | 2 |
| Dosing frequency | pulsed 2 days/month (Mayo protocol) or daily continuous (empirical) | daily |
| Routes | oral | topical, subcutaneous |
| Onset (hr) | 1 | 24 |
| Peak (hr) | 4 | 168 |
| Molecular weight | 286.24 | 340.85 |
| Molecular formula | C15H10O6 | C14H24N6O4 (GHK alone); C14H22CuN6O4 with Cu(II) |
| Mechanism | Senolytic via Bcl-2 family inhibition (Bcl-xL, Bcl-w); broad polyphenol with Nrf2 activation, mTOR inhibition at high concentrations, and antioxidant effects. | Tripeptide that chelates Cu(II) and delivers it to copper-dependent enzymes (lysyl oxidase, superoxide dismutase). Modulates expression of >4000 genes toward a younger profile in fibroblast culture, including upregulation of decorin and downregulation of pro-inflammatory cytokines. |
| Legal status | OTC dietary supplement | Topical cosmetics legal in most jurisdictions; injectable form not FDA approved for any indication; research-use-only grey market |
| WADA status | allowed | allowed |
| DEA / Rx | OTC supplement | Topical OTC (cosmetic); injectable not FDA approved; research-chemical status |
| Pregnancy | Insufficient data | Insufficient data; topical use likely low-risk; injectable not recommended |
| CAS | 528-48-3 | 49557-75-7 |
| PubChem CID | 5281614 | 73587 |
| Wikidata | Q230614 | Q3104638 |
Safety profile
Fisetin
Common side effects
- mild GI upset
- headache (rare)
Contraindications
- active cancer (theoretical, polyphenol interactions)
- pregnancy and lactation (insufficient data)
- concurrent CYP3A4-sensitive medications
Interactions
- statins (CYP3A4 substrates): theoretical reduction in statin clearance at high fisetin doses(minor)
- warfarin: theoretical CYP-mediated interaction; monitor INR if combining(moderate)
- other senolytics (rapamycin, dasatinib + quercetin): additive senolytic effect; pairing is investigational(minor)
GHK-Cu
Common side effects
- mild erythema at topical site
- transient itch
- blue-green discoloration of injection site (copper)
- rare contact dermatitis
Contraindications
- copper allergy
- Wilson disease
- open wound near injection site (caution)
- pregnancy (no data)
Interactions
- topical retinoids: additive irritation; alternate days or apply at different times(minor)
- topical vitamin C (ascorbic acid): ascorbate reduces Cu(II) to Cu(I), which can destabilize the GHK-Cu complex; separate by 30 minutes(minor)
Which Should You Take?
Fisetin comes out ahead for most readers on the criteria we weight: 2 catalogued goals, OTC dietary supplement, oral dosing, with a Tier-B outcome catalogued. GHK-Cu is the right call when one of the conditionals below applies.
- → If your priority is focus or working memory, pick Fisetin.
- → If your priority is skin health, pick GHK-Cu.
- → If your priority is wound healing, pick GHK-Cu.
Edge case: If you want to avoid research-only / gray-market sourcing, Fisetin is the more accessible choice.
Default choice: Fisetin. Lower friction to source, and broader goal coverage. Reach for GHK-Cu only if your priority sits squarely in the goals it owns above.
This verdict is generated from each compound's schema (goals, legal status, evidence outcomes, dosing route). It updates automatically as our compound data evolves; the deeper read sits on each individual compound page.
Common questions
What is the difference between Fisetin and GHK-Cu?
Fisetin and GHK-Cu differ in category (supplement vs peptide), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Fisetin or GHK-Cu?
Fisetin half-life is 2 hours; GHK-Cu half-life is 0.5 hours.
Can you stack Fisetin with GHK-Cu?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
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