Fisetin (flavonol from strawberries, mangoes and onions)

Fisetin is a flavonol found in plants such as strawberries, mango and onion. It is marketed as an anti-aging and longevity supplement, often as a senolytic that clears senescent cells. In people, no convincing benefit for this use has been shown – there is no solid evidence that it slows aging or extends lifespan. What does help with healthy aging is well established: regular physical activity, sleep, a sensible diet, and keeping blood pressure, glucose and lipids in check, along with not smoking. Fisetin should not be taken instead of measures and treatments with proven benefit, since that can mean missing care that actually works.

Fisetin is sold as a «natural oncoprotector» via laboratory pro-apoptotic data on tumour cells. No RCTs with cancer incidence or mortality endpoints in humans. USPSTF 2022 recommends against routine vitamin-mineral supplement use for cancer prevention (D recommendation). ESMO 2020 lists smoking cessation, weight normalisation, physical activity, alcohol restriction, UV protection, HPV and HBV vaccination, age-appropriate screening as primary prevention. If fisetin was recommended as «cancer prevention», consider seeking a second opinion from an oncologist.

Fisetin is a plant flavonol (from strawberries, mango, onion) marketed as a supplement for memory and concentration. There is no convincing evidence of benefit for this use; the human data on memory and attention do not back it up. What actually helps cognition: enough sleep, regular physical activity, and treating conditions that make it hard to focus. If memory or concentration worries you, talk it over with your doctor.