Comparison
Fisetin vs L-Theanine
Side-by-side of Fisetin and L-Theanine. 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.
L-Theanine
L-theanine is a non-protein amino acid found in tea leaves. The most-replicated nootropic; pairs with caffeine at 1:1 (100-200 mg each) for acute focus.
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
L-Theanine
- •Non-protein amino acid in tea; the most-replicated nootropic in the human RCT literature
- •Caffeine + theanine at 1:1 (100-200 mg each) is the gold-standard acute focus stack
- •Solo doses of 200-400 mg reduce subjective stress and improve sleep quality
- •Increases alpha-wave EEG activity within 30-45 minutes of 200 mg oral dose
- •Crosses blood-brain barrier; bioavailability high, half-life 60-90 minutes
- •Clean safety record; minimal interactions at supplement doses
Side-by-side
| Attribute | Fisetin | L-Theanine |
|---|---|---|
| Category | supplement | supplement |
| Also known as | 3,7,3',4'-tetrahydroxyflavone | theanine, gamma-glutamylethylamide |
| Half-life (hr) ↗ | 2 | 1.5 |
| Typical dose (mg) ↗ | 500 | 200 |
| Dosing frequency | pulsed 2 days/month (Mayo protocol) or daily continuous (empirical) | as needed (with caffeine) or daily |
| Routes | oral | oral |
| Onset (hr) | 1 | 0.5 |
| Peak (hr) | 4 | 1 |
| Molecular weight | 286.24 | 174.2 |
| Molecular formula | C15H10O6 | C7H14N2O3 |
| Mechanism | Senolytic via Bcl-2 family inhibition (Bcl-xL, Bcl-w); broad polyphenol with Nrf2 activation, mTOR inhibition at high concentrations, and antioxidant effects. | Crosses BBB; modulates GABA/dopamine/serotonin (modest); increases alpha-wave EEG activity; dampens stress-induced sympathetic response without sedation. |
| Legal status | OTC dietary supplement | OTC dietary supplement |
| WADA status | allowed | allowed |
| DEA / Rx | OTC supplement | OTC supplement |
| Pregnancy | Insufficient data | Insufficient supplement-dose data; tea-source intake safe |
| CAS | 528-48-3 | 3081-61-6 |
| PubChem CID | 5281614 | 439378 |
| Wikidata | Q230614 | Q909931 |
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)
L-Theanine
Common side effects
- mild GI upset (rare)
- headache (rare)
Contraindications
- pregnancy / lactation (insufficient data at supplement doses)
- concurrent strong GABAergics without caution
Interactions
- caffeine: synergistic for acute focus; dampens jitter without blunting alertness(minor)
- benzodiazepines / alcohol: potential additive sedation(minor)
Which Should You Take?
L-Theanine comes out ahead for most readers on the criteria we weight: 3 catalogued goals, OTC dietary supplement, oral dosing, with a Tier-A outcome catalogued. Fisetin is the right call when one of the conditionals below applies.
- → If your priority is healthspan extension, pick Fisetin.
- → If your priority is stress and HPA-axis regulation, pick L-Theanine.
- → If your priority is sleep onset or sleep quality, pick L-Theanine.
Default choice: L-Theanine. Lower friction to source, a Tier-A evidence outcome catalogued, and broader goal coverage. Reach for Fisetin 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 L-Theanine?
Fisetin and L-Theanine differ in category (supplement vs supplement), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Fisetin or L-Theanine?
Fisetin half-life is 2 hours; L-Theanine half-life is 1.5 hours.
Can you stack Fisetin with L-Theanine?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
Go deeper