Fisetin
fisetin
A plant flavonoid studied as a senolytic to clear senescent cells.
TypeSupplement / dietary
Grade
C
Limited
- Class
- Senolytics
- Primary use
- Senolytic action
- Evidence strength
- low
- Last reviewed
- 2026-07-01
Bottom line
One of the more promising natural senolytics in the lab — but the human evidence is still in progress. Clinical trials are underway; the results aren't in. Treat current claims as preliminary.
What the evidence says
Fisetin extended healthspan and reduced senescent-cell burden in animal models and is among the most-studied natural senolytics preclinically. Human trials (for example in frailty and inflammation) are ongoing but have not yet delivered clear efficacy data, and — as with quercetin — its oral bioavailability is limited. Grade C reflects genuine preclinical promise sitting on top of an immature human evidence base. The gap between 'works in mice' and 'proven in people' is exactly where the marketing tends to skip.
Key studies
Mechanism
Proposed senolytic activity by pushing senescent cells toward apoptosis, alongside general antioxidant and anti-inflammatory flavonoid effects.
Safety
Consumed as a dietary flavonoid (strawberries, apples) with good tolerability at food levels. The high intermittent 'senolytic' doses used in research are less characterised for long-term safety.
Dosage context
Research uses intermittent high-dose ('hit-and-run') regimens; supplement doses and bioavailability vary widely. No validated human protocol yet exists.
From the field
Fisetin is often sold as if the human trials were already positive. They aren't finished. We grade it C and will revisit the day the clinical data actually land.