Fisetin + Quercetin Stack: Broad-Spectrum Senolytic Protocol
Expert Summary
Fisetin and quercetin represent the best-evidenced natural senolytic combination. Fisetin preferentially inhibits BCL-W and BCL-XL survival proteins; quercetin preferentially inhibits BCL-2. Together they cover the three primary BCL-2 family anti-apoptotic proteins expressed in senescent cells, making this combination significantly more effective than either agent alone.
Key Facts
- BCL-2 family coverage: BCL-2 (quercetin inhibits at ~12 μM), BCL-XL (fisetin and quercetin inhibit), BCL-W (fisetin preferentially inhibits). Complete BCL-2 family coverage achieved with the combination.
- Protocol: Day 1–2 (monthly): Fisetin 500–1,000 mg + Quercetin phytosome 500–1,000 mg, taken in 2 divided doses with fat-containing meals.
- Bioavailability sync: Both fisetin and quercetin benefit from fat co-administration — a practical advantage since both can be taken simultaneously with a fatty meal.
- Continuous vs burst: Maintain quercetin phytosome 200 mg/day continuously for anti-inflammatory benefits. Use fisetin only on burst days (no daily fisetin between bursts). Increase quercetin to 500–1,000 mg on burst days.
- Add spermidine: Add spermidine 2–4 mg/day continuous to prevent new senescent cell accumulation between fisetin/quercetin burst days.
- Evidence alignment: Fisetin+quercetin approximates the natural component of the D+Q protocol (quercetin) with the addition of the strongest natural senolytic (fisetin). This is the closest OTC approach to the clinical D+Q evidence base.
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Frequently Asked Questions
Is fisetin+quercetin as effective as dasatinib+quercetin?
The D+Q combination has stronger human clinical evidence. Fisetin+quercetin is the most effective OTC natural alternative. For most people in their 40s–50s, fisetin+quercetin is a reasonable starting point before considering physician-supervised D+Q.
What ratio of fisetin to quercetin is best?
1:1 ratio (500 mg each) is the most commonly used protocol. Some practitioners emphasize fisetin more heavily (2:1 fisetin:quercetin) based on its stronger preclinical senolytic data.
Can I take both every day instead of cycling?
Daily use at sub-senolytic doses provides anti-inflammatory benefits but does not achieve the burst plasma concentrations needed for senolysis. Burst dosing is essential for the senolytic mechanism.
Scientific References
- Yousefzadeh MJ et al. Fisetin is a senotherapeutic that extends health and lifespan. EBioMedicine. 2018. PMID: 30279143
- Xu M et al. Senolytics improve physical function and increase lifespan in old age. Nature Medicine. 2018. PMID: 29988130