Fisetin
Fisetin is a natural flavonoid compound found in strawberries and other fruits that has gained attention for its potential senolytic properties - the ability to help clear damaged 'senescent' cells from the body. Research suggests it may support cellular health and cognitive function, though human studies are still limited. Dietary supplements are not FDA-approved to diagnose, treat, cure, or prevent any disease. Consult your doctor before starting any supplement.
Key Takeaways
- Fisetin acts as a senolytic, helping clear damaged 'zombie' cells from the body, with research suggesting 20mg per kg of body weight taken intermittently rather than daily
- Most effective when taken with fats for better absorption, as standard fisetin has relatively poor bioavailability on its own
- Dietary sources like strawberries don't provide research-effective doses - supplements offering 100-500mg are more practical for potential benefits
- Limited human studies exist, with most research conducted in animals, so long-term safety data in humans is still developing
- May be most beneficial for adults 50+ seeking cellular health support, though consultation with healthcare providers is essential
How to Take
Typical Dosage
100-200 mg daily for general use, though clinical trials have used higher doses (20 mg per kg of body weight intermittently). Most supplements provide 100-500 mg per dose. Optimal dosing is still being researched in humans.
When to Take
Take with meals containing fat to improve absorption, as fisetin has relatively low bioavailability on its own. Some protocols suggest intermittent 'pulse' dosing rather than daily use.
Why It Matters for Ages 50+
Adults over 50 may benefit from fisetin's potential senolytic properties, as cellular senescence increases with age and contributes to age-related health decline. Research suggests it may support cognitive function and help clear damaged cells that accumulate over time. However, bioavailability decreases with age, making proper dosing and timing more critical for this population.
What to Look For
- Look for supplements that include absorption enhancers or liposomal/micellized formulations for better bioavailability
- Choose products with third-party testing for purity and potency, as fisetin quality can vary significantly between manufacturers
- Verify the supplement contains pure fisetin or beneficial combinations with quercetin, rather than proprietary blends with undisclosed amounts
- Ensure proper packaging that protects from light and moisture, as flavonoids can degrade when exposed to these elements
- Select reputable brands that provide clear dosage information and follow good manufacturing practices (GMP certification)
Potential Interactions
Be aware of these potential interactions:
- Anticoagulants (warfarin, aspirin, Plavix, Eliquis, Xarelto): May enhance anticoagulant effects and increase bleeding risk due to antiplatelet activity
- Medications metabolized by CYP2C9 and CYP2C19 enzymes: May inhibit these liver enzymes, potentially affecting drug metabolism
- Chemotherapy agents: May interact with cancer treatments, affecting their efficacy or toxicity
- Blood pressure medications: Potential interactions not well-studied, monitor blood pressure closely
- Any prescription medications: Limited interaction data available, consult your pharmacist
Who Should Avoid This Supplement
- Pregnant and breastfeeding women due to lack of safety data in these populations
- Children and adolescents, as research has focused on adult populations and safety is not established for younger ages
- People with bleeding disorders or those scheduled for surgery, due to potential antiplatelet effects that may increase bleeding risk
- Individuals with liver disease, as fisetin may affect liver enzyme function and drug metabolism
Recommended by Experts
“Included in longevity stack for cellular repair”
“Takes 500mg for senolytic properties”
Frequently Asked Questions
Research suggests 20mg per kg of body weight taken intermittently in a 'hit and run' approach rather than daily. Most supplements provide 100-500mg, and taking with fats significantly improves absorption.
No, dietary sources don't provide research-effective doses. You'd need to consume impractical amounts of strawberries to reach the levels used in studies, making supplements more viable.
Fisetin is generally well-tolerated with no serious side effects reported in early human research. Some people may experience mild digestive upset, and rare allergic reactions could include itching or skin rashes.
Some research suggests fisetin and quercetin may have synergistic effects when combined, and many commercial products pair them together. However, this also increases potential drug interactions, so medical consultation is important.
The timeline for benefits isn't well-established in humans since most research is preclinical. Senolytic effects may occur relatively quickly, but measurable health improvements likely require longer-term use under medical guidance.
While animal studies show good safety even at high doses, long-term human safety data is limited. The intermittent dosing approach used in research may be safer than daily supplementation for extended periods.