{"product_id":"quercetin-500mg-senolytic-flavonoid-natural-antihistamine","title":"Quercetin 500mg | Senolytic Flavonoid + Natural Antihistamine","description":"\u003ch2\u003eQuercetin 500mg + BioPerine — the human-trialed senolytic flavonoid (Mayo D+Q protocol)\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eThe 30-second answer.\u003c\/strong\u003e Quercetin is a plant flavonoid found in onions, capers, apples and tea that does three different things at once: it acts as a \u003cem\u003esenolytic\u003c\/em\u003e (selectively triggers apoptosis in zombie \/ senescent cells, especially when paired with dasatinib in the Mayo Clinic D+Q protocol), it stabilises mast cells and dampens histamine release (Pearce 1984, Mlcek 2016), and it inhibits NF-κB-driven inflammation upstream of the same TNF-α\/IL-6 axis as curcumin (Endale 2013). The dose used in the original human senolytic trial — Justice 2019 in \u003cem\u003eEBioMedicine\u003c\/em\u003e, the first-in-human D+Q readout in idiopathic pulmonary fibrosis, and Hickson 2019 in \u003cem\u003eEBioMedicine\u003c\/em\u003e, the first D+Q readout in diabetic kidney disease — was 1,000 mg quercetin (with 100 mg dasatinib) for two consecutive days. This bottle delivers 500 mg quercetin dihydrate plus 5 mg BioPerine® (piperine, 95% standardised) per capsule, so two capsules on a hit-day match the human-trialed senolytic dose without prescription dasatinib; one capsule a day is the daily-antihistamine \/ cardioprotective dose used in Edwards 2007 and Egert 2009. Vegan, HPLC-verified ≥ 98% quercetin, third-party tested, made under cGMP in the USA. \u003ca href=\"\/he\/collections\/senolytics\"\u003eSenolytics collection\u003c\/a\u003e · \u003ca href=\"\/he\/collections\/foundational-health\"\u003eFoundational Health\u003c\/a\u003e.\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWhat it is:\u003c\/strong\u003e 500 mg quercetin dihydrate (≥ 98% by HPLC) + 5 mg BioPerine®, vegan HPMC capsule, 60 count.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMechanism layers:\u003c\/strong\u003e senolytic (BCL-xL \/ PI3K-AKT survival pathway in zombie cells) · NF-κB \/ TNF-α \/ IL-6 inhibition · mast-cell stabiliser · SIRT1 co-activator · zinc-ionophore.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eTrial-validated doses:\u003c\/strong\u003e 1,000 mg\/day on hit-days for D+Q-style senolytic pulses (Justice 2019, Hickson 2019); 150–500 mg\/day daily for cardiovascular \u0026amp; allergy endpoints (Edwards 2007, Egert 2009).\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePairs natively with:\u003c\/strong\u003e \u003ca href=\"\/he\/products\/fisetin-500mg-senolytic-flavonoid-for-cellular-cleanup\"\u003eFisetin 500mg\u003c\/a\u003e (the other Mayo-ranked senolytic flavonoid), \u003ca href=\"\/he\/products\/curcumin-1000mg-bioperine-anti-inflammatory-longevity\"\u003eCurcumin 1000mg+BioPerine\u003c\/a\u003e (the NF-κB \/ Nrf2 partner), \u003ca href=\"\/he\/products\/resveratrol-600mg-60-capsules-30-day-supply\"\u003eResveratrol 600mg\u003c\/a\u003e (SIRT1 substrate), and \u003ca href=\"\/he\/products\/pure-nmn-500mg-60-capsules-30-day-supply\"\u003eNMN 500mg\u003c\/a\u003e (NAD+ substrate the cleared cell space gets refilled with).\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWhy this bottle:\u003c\/strong\u003e ≥ 98% HPLC-verified quercetin (most market quercetin is 95% rutin-derived) + branded BioPerine® for the documented ~20× quercetin-AUC bioavailability boost (Khan 2014).\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhy a humble onion flavonoid ended up in serious longevity research\u003c\/h2\u003e\n\n\u003cp\u003eQuercetin is one of the most-studied flavonoids in the dietary literature — over 30,000 PubMed entries — and was for decades treated as a \"general antioxidant\" with mild allergy-modulating activity. Two unrelated discoveries changed that. First, mast-cell biologists in the 1980s (Pearce 1984) showed that quercetin doesn't just scavenge oxidants — it stabilises the membrane of mast cells, the same cells cromolyn sodium targets, and prevents the IgE-triggered degranulation that releases histamine. Second, in 2015, Zhu et al. (\u003cem\u003eAging Cell\u003c\/em\u003e) screened 46 compounds in cellular-senescence assays at the Mayo Clinic and identified two — dasatinib (a tyrosine-kinase inhibitor) and quercetin (a flavonoid) — as the first known \u003cem\u003esenolytics\u003c\/em\u003e: agents that selectively trigger apoptosis in senescent cells while sparing healthy cells. By 2018, the same group (Xu 2018, \u003cem\u003eNature Medicine\u003c\/em\u003e) had shown that intermittent D+Q pulses extended healthy lifespan in aged mice and reduced senescence markers across multiple tissues. By 2019, Justice and Hickson had published the first two human readouts (idiopathic pulmonary fibrosis and diabetic kidney disease) demonstrating that the protocol could be tolerated, that p16+ senescent-cell burden could be reduced, and that physical-function and renal endpoints moved in the predicted direction.\u003c\/p\u003e\n\n\u003cp\u003eThat is why quercetin sits in two different rooms of the longevity protocol: it is a foundational, daily, anti-inflammatory \/ antihistamine \/ cardioprotective flavonoid that pairs with curcumin and omega-3 — and it is also a senolytic that, on hit-days (typically two consecutive days, repeated every 4–12 weeks), participates in the dasatinib-and-quercetin Mayo protocol or in over-the-counter analogues built around fisetin and quercetin.\u003c\/p\u003e\n\n\u003ch2\u003eWhat quercetin actually does — the five-layer mechanism\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003e1. Senolytic activity (BCL-xL \/ PI3K-AKT survival pathway).\u003c\/strong\u003e Senescent cells survive past their replicative shelf-life by upregulating anti-apoptotic networks called SCAPs — Senescence-associated Anti-apoptotic Pathways — of which BCL-xL, PI3K-AKT and serpins are the most studied (Zhu 2015). Quercetin disrupts the PI3K\/AKT and BCL-xL arms; dasatinib hits the ephrin-receptor tyrosine kinase arm; together they cover the SCAP map in a way neither does alone. Fisetin appears to hit the same set with a slightly different selectivity profile (Yousefzadeh 2018, \u003cem\u003eEBioMedicine\u003c\/em\u003e), which is why fisetin and quercetin are usually run on alternating senolytic protocols rather than same-day.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e2. NF-κB \/ TNF-α \/ IL-6 \/ inflammaging axis.\u003c\/strong\u003e Quercetin inhibits IκB-kinase activity and the nuclear translocation of NF-κB p65, the same upstream pathway as curcumin (Endale 2013, \u003cem\u003eImmunobiology\u003c\/em\u003e). Downstream, this reduces TNF-α, IL-6, IL-1β, COX-2 and iNOS — the same cytokine cluster that defines \"inflammaging\" (Franceschi 2018) and that drives the SASP (senescence-associated secretory phenotype) of the senescent cells quercetin also clears. In other words: quercetin clears the cells \u003cem\u003eand\u003c\/em\u003e mutes the signal those cells were sending while alive.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e3. Mast-cell \/ histamine \/ allergy modulation.\u003c\/strong\u003e Quercetin stabilises mast-cell membranes, inhibits IgE-mediated histamine release, and reduces leukotriene synthesis (Pearce 1984, Mlcek 2016, Weng 2012). This is why quercetin is found in many \"natural antihistamine\" stacks — it is doing the same job cromolyn does, just upstream of the symptom. Clinically, this shows up most reliably in seasonal-allergic-rhinitis and exercise-induced bronchospasm trials (Yamada 2024, Jafarinia 2020).\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e4. SIRT1 co-activator and AMPK.\u003c\/strong\u003e Quercetin induces SIRT1 deacetylase activity (de Boer 2005, Howitz 2003 — the same screen that surfaced resveratrol) and activates AMPK (Ahn 2008). This is the reason quercetin shows up in the Sinclair-style classic stacks alongside resveratrol and NMN — it is not the strongest single SIRT1 activator (resveratrol and pterostilbene are larger effectors), but it is the most studied flavonoid that contributes to the same signalling shape.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003e5. Zinc ionophore and antiviral activity.\u003c\/strong\u003e Quercetin is a zinc ionophore — it transports zinc across cell membranes — which is why it surged into the public consciousness during the COVID-19 era as part of zinc-quercetin-vitamin-D-vitamin-C protocols (Saeedi-Boroujeni 2021). The most direct-mechanism evidence is Pawar 2022 \/ Di Pierro 2021, both showing reduced symptom-day burden in early infection. We make no clinical claims here — this is included for mechanistic completeness; quercetin's daily-flavonoid case stands on cardiovascular and inflammatory endpoints, not on antiviral marketing.\u003c\/p\u003e\n\n\u003ch2\u003eTrial-validated doses and what the human studies actually showed\u003c\/h2\u003e\n\n\u003ctable border=\"1\" cellpadding=\"6\" cellspacing=\"0\" style=\"border-collapse:collapse;width:100%;\"\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eTrial\u003c\/th\u003e\n\u003cth\u003en \/ population\u003c\/th\u003e\n\u003cth\u003eDose \/ schedule\u003c\/th\u003e\n\u003cth\u003eEndpoint \u0026amp; result\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eJustice 2019\u003cbr\u003e\u003cem\u003eEBioMedicine\u003c\/em\u003e\n\u003c\/td\u003e\n\u003ctd\u003e14 adults with idiopathic pulmonary fibrosis\u003c\/td\u003e\n\u003ctd\u003eDasatinib 100mg + Quercetin 1,000mg \/ day × 3 days\/week × 3 weeks\u003c\/td\u003e\n\u003ctd\u003eFirst-in-human senolytic readout: physical-function endpoints (6-Minute Walk Distance, gait speed, chair stand) improved at 1 week post-treatment; well tolerated.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eHickson 2019\u003cbr\u003e\u003cem\u003eEBioMedicine\u003c\/em\u003e\n\u003c\/td\u003e\n\u003ctd\u003e9 adults with diabetic kidney disease\u003c\/td\u003e\n\u003ctd\u003eDasatinib 100mg + Quercetin 1,000mg \/ day × 3 consecutive days\u003c\/td\u003e\n\u003ctd\u003e11 days post-treatment: reduced p16INK4a+ and p21CIP1+ senescent-cell burden in adipose \u0026amp; skin biopsies; reduced circulating SASP factors (IL-1α, IL-6, MMPs).\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEdwards 2007\u003cbr\u003e\u003cem\u003eJ Nutr\u003c\/em\u003e\n\u003c\/td\u003e\n\u003ctd\u003e41 prehypertensive \u0026amp; stage-1 hypertensive adults\u003c\/td\u003e\n\u003ctd\u003e730 mg\/day × 28 days\u003c\/td\u003e\n\u003ctd\u003eSBP −7 mmHg, DBP −5 mmHg in the stage-1 group; no effect in the prehypertensive group.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEgert 2009\u003cbr\u003e\u003cem\u003eBr J Nutr\u003c\/em\u003e\n\u003c\/td\u003e\n\u003ctd\u003e93 overweight \/ obese adults with metabolic-syndrome traits\u003c\/td\u003e\n\u003ctd\u003e150 mg\/day × 6 weeks\u003c\/td\u003e\n\u003ctd\u003eSBP −2.6 mmHg in the apoE3 subgroup; oxidised-LDL −0.31 µg\/mL; serum HDL ↑.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePfeuffer 2013\u003cbr\u003e\u003cem\u003eMol Nutr Food Res\u003c\/em\u003e\n\u003c\/td\u003e\n\u003ctd\u003e49 male smokers, randomised crossover\u003c\/td\u003e\n\u003ctd\u003e150 mg\/day × 8 weeks\u003c\/td\u003e\n\u003ctd\u003eReduced waist circumference, TNF-α, postprandial systolic BP.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrüll 2017\u003cbr\u003e\u003cem\u003eBr J Nutr\u003c\/em\u003e\n\u003c\/td\u003e\n\u003ctd\u003e70 hypertensive adults\u003c\/td\u003e\n\u003ctd\u003e162 mg\/day from onion-skin extract × 6 weeks\u003c\/td\u003e\n\u003ctd\u003e24-hr SBP −3.6 mmHg in the hypertensive subgroup.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eYamada 2022\u003cbr\u003e\u003cem\u003eFood Sci Biotechnol\u003c\/em\u003e\n\u003c\/td\u003e\n\u003ctd\u003e69 adults with mild seasonal allergy symptoms\u003c\/td\u003e\n\u003ctd\u003e200 mg\/day enzymatically-modified isoquercitrin × 8 weeks\u003c\/td\u003e\n\u003ctd\u003eReduced ocular itching and nasal-symptom scores vs. placebo.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eJafarinia 2020 (review)\u003cbr\u003e\u003cem\u003eAllergy Asthma Clin Immunol\u003c\/em\u003e\n\u003c\/td\u003e\n\u003ctd\u003ePooled allergic-rhinitis and bronchospasm RCTs\u003c\/td\u003e\n\u003ctd\u003e200–500 mg\/day\u003c\/td\u003e\n\u003ctd\u003eConsistent reduction in histamine-driven symptoms; comparable effect-size to second-generation antihistamines without sedation.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eKhan 2014\u003cbr\u003e\u003cem\u003ePhytother Res\u003c\/em\u003e\n\u003c\/td\u003e\n\u003ctd\u003eHealthy volunteers, pharmacokinetic crossover\u003c\/td\u003e\n\u003ctd\u003e500 mg quercetin ± 20 mg piperine\u003c\/td\u003e\n\u003ctd\u003e~20× increase in quercetin plasma AUC with piperine co-administration.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eKnab 2011\u003cbr\u003e\u003cem\u003eMed Sci Sports Exerc\u003c\/em\u003e\n\u003c\/td\u003e\n\u003ctd\u003e30 trained cyclists, double-blind\u003c\/td\u003e\n\u003ctd\u003e1,000 mg\/day × 3 weeks\u003c\/td\u003e\n\u003ctd\u003e+13% time-to-exhaustion; mitochondrial-biogenesis markers up.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003cp\u003eRead across the table the way the literature reads: the senolytic story is hit-and-recover (1,000 mg\/day for 2–3 days every 1–3 months, paired with dasatinib in the Mayo trials), the daily story is sustained (150–500 mg\/day for cardiovascular, allergy and inflammation endpoints over 4–8 weeks), and the bioavailability story (Khan 2014) is the reason every serious quercetin product now ships with piperine.\u003c\/p\u003e\n\n\u003ch2\u003eForms of quercetin compared\u003c\/h2\u003e\n\n\u003ctable border=\"1\" cellpadding=\"6\" cellspacing=\"0\" style=\"border-collapse:collapse;width:100%;\"\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eForm\u003c\/th\u003e\n\u003cth\u003eActive\u003c\/th\u003e\n\u003cth\u003eBioavailability\u003c\/th\u003e\n\u003cth\u003eBest for\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eQuercetin aglycone (anhydrous)\u003c\/td\u003e\n\u003ctd\u003e~100% quercetin\u003c\/td\u003e\n\u003ctd\u003ePoor (~ 1–2% absorbed without piperine)\u003c\/td\u003e\n\u003ctd\u003eBench \/ formulation; rarely sold as finished consumer SKU.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eQuercetin dihydrate + BioPerine® (this bottle)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e~93% quercetin (rest = 2 water + piperine)\u003c\/td\u003e\n\u003ctd\u003e~20× vs. aglycone alone (Khan 2014); the cost-efficient trial-matched form\u003c\/td\u003e\n\u003ctd\u003e\u003cstrong\u003eThe default consumer form for D+Q senolytic protocols and daily cardiovascular\/allergy use.\u003c\/strong\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEnzymatically-modified isoquercitrin (EMIQ)\u003c\/td\u003e\n\u003ctd\u003eGlycosylated quercetin\u003c\/td\u003e\n\u003ctd\u003e~10–17× vs. aglycone alone\u003c\/td\u003e\n\u003ctd\u003eDaily allergy-symptom trials (Yamada 2022, Murota 2018); premium price.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eQuercetin phytosome (Quercefit® \/ lecithin)\u003c\/td\u003e\n\u003ctd\u003ePhospholipid-complexed\u003c\/td\u003e\n\u003ctd\u003e~20× vs. aglycone alone\u003c\/td\u003e\n\u003ctd\u003ePremium daily; some studies in COVID-recovery.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLiposomal quercetin\u003c\/td\u003e\n\u003ctd\u003ePhospholipid-encapsulated, often liquid\u003c\/td\u003e\n\u003ctd\u003e~10–30× vs. aglycone alone\u003c\/td\u003e\n\u003ctd\u003ePeople who can't swallow capsules; expensive per mg.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRutin \/ hesperidin \/ \"bioflavonoid complex\"\u003c\/td\u003e\n\u003ctd\u003e~5–25% quercetin equivalents after gut conversion\u003c\/td\u003e\n\u003ctd\u003eVariable \/ low\u003c\/td\u003e\n\u003ctd\u003eVitamin-C synergy historical use; not a quercetin replacement.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWhole-food: red onion, capers, apple skins, kale, tea\u003c\/td\u003e\n\u003ctd\u003e~3–230 mg\/100g (capers highest)\u003c\/td\u003e\n\u003ctd\u003ePoor without absorption enhancer\u003c\/td\u003e\n\u003ctd\u003eFoundational diet; insufficient to reach 150 mg\/day quercetin without supplementation.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eHow to stack quercetin (and what it pairs natively with)\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eSenolytic layer (hit-days, every 4–12 weeks).\u003c\/strong\u003e Two capsules of this Quercetin 500mg + BioPerine on day 1 and day 2 (= 1,000 mg\/day, the Justice 2019 \/ Hickson 2019 dose), optionally on day 3. The Mayo D+Q protocol uses prescription dasatinib in addition — over-the-counter analogues replace dasatinib with \u003ca href=\"\/he\/products\/fisetin-500mg-senolytic-flavonoid-for-cellular-cleanup\"\u003eFisetin 500mg\u003c\/a\u003e (Yousefzadeh 2018), at 1,000–2,000 mg fisetin on the same hit-days. We do not sell dasatinib and we do not recommend self-prescribing it; we describe the protocol because it is the published reference frame.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eInflammation layer (daily).\u003c\/strong\u003e One capsule daily at 500 mg quercetin pairs upstream with \u003ca href=\"\/he\/products\/curcumin-1000mg-bioperine-anti-inflammatory-longevity\"\u003eCurcumin 1000mg + BioPerine\u003c\/a\u003e (the same NF-κB axis, downstream-different cytokine targeting), \u003ca href=\"\/he\/products\/omega-3-fish-oil-2000mg-epa-dha\"\u003eOmega-3 EPA\/DHA 2000mg\u003c\/a\u003e (resolvin synthesis upstream of the same prostaglandin-cascade quercetin tunes), and the antioxidant flank of \u003ca href=\"\/he\/products\/glutathione-500mg-maximum-strength\"\u003eGlutathione 500mg\u003c\/a\u003e + \u003ca href=\"\/he\/products\/n-acetyl-cysteine-600mg-nac-glutathione-precursor-for-antioxidant-longevity-support\"\u003eNAC 600mg\u003c\/a\u003e.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eSirtuin \/ NAD+ classic layer.\u003c\/strong\u003e 250–500 mg quercetin daily alongside \u003ca href=\"\/he\/products\/resveratrol-600mg-60-capsules-30-day-supply\"\u003eResveratrol 600mg\u003c\/a\u003e + \u003ca href=\"\/he\/products\/pure-nmn-500mg-60-capsules-30-day-supply\"\u003eNMN 500mg\u003c\/a\u003e (or \u003ca href=\"\/he\/products\/nmn-1000mg-double-strength-60-capsules-30-day-supply\"\u003eNMN 1000mg\u003c\/a\u003e) is the most-asked Sinclair-style stack. The mechanism logic: NMN refills the NAD+ pool the cleared senescent cells were depleting, resveratrol activates SIRT1, quercetin contributes to SIRT1 activity and clears the pro-SASP cells in the background. Adding \u003ca href=\"\/he\/products\/pterostilbene-100mg-trans-sirt1-activator-resveratrol-cousin\"\u003ePterostilbene 100mg\u003c\/a\u003e to that stack is the bioavailable-resveratrol-cousin upgrade.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eHistamine \/ allergy layer.\u003c\/strong\u003e 250–500 mg quercetin daily 4–6 weeks before allergy season starts (mast-cell stabilisers take time to load) plus \u003ca href=\"\/he\/products\/liposomal-vitamin-c-1000mg-maximum-absorption-antioxidant-formula\"\u003eLiposomal Vitamin C 1000mg\u003c\/a\u003e (vitamin C extends quercetin's plasma half-life and contributes its own antihistamine effect, Johnston 1996) and \u003ca href=\"\/he\/products\/multi-collagen-peptides-powder-5-types-unflavored-1lb\"\u003ecollagen peptides\u003c\/a\u003e for gut-barrier support.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eCardiovascular \/ metabolic layer.\u003c\/strong\u003e 150–500 mg quercetin daily alongside \u003ca href=\"\/he\/products\/coq10-400mg-maximum-strength\"\u003eCoQ10 400mg\u003c\/a\u003e (the Q-SYMBIO \/ statin-support flank), \u003ca href=\"\/he\/products\/taurine-1000mg-cardiovascular-mitochondrial-longevity\"\u003eTaurine 1000mg\u003c\/a\u003e (the Singh 2023 Science cardiovascular flank) and \u003ca href=\"\/he\/products\/berberine-hcl-500mg-maximum-strength\"\u003eBerberine HCl 500mg\u003c\/a\u003e for the AMPK \/ glucose flank.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eMitochondrial \/ autophagy layer.\u003c\/strong\u003e Quercetin is one of three molecules — quercetin, fisetin, urolithin A — that span both the senolytic and the mitophagy\/autophagy maps. Pair with \u003ca href=\"\/he\/products\/urolithin-a-500mg-mitophagy-activator\"\u003eUrolithin A 500mg\u003c\/a\u003e (PINK1\/Parkin mitophagy activator), \u003ca href=\"\/he\/products\/spermidine-10mg-wheat-germ-extract\"\u003eSpermidine 10mg\u003c\/a\u003e (autophagy inducer), and \u003ca href=\"\/he\/products\/pqq-20mg-mitochondrial-biogenesis-activator\"\u003ePQQ 20mg\u003c\/a\u003e (mitochondrial biogenesis) to cover clearance + replacement.\u003c\/p\u003e\n\n\u003cp\u003eBrowse the full mechanism collections: \u003ca href=\"\/he\/collections\/senolytics\"\u003eSenolytics\u003c\/a\u003e · \u003ca href=\"\/he\/collections\/foundational-health\"\u003eFoundational Health\u003c\/a\u003e · \u003ca href=\"\/he\/collections\/antioxidants\"\u003eAntioxidants\u003c\/a\u003e · \u003ca href=\"\/he\/collections\/cardiovascular-longevity\"\u003eCardiovascular Longevity\u003c\/a\u003e · \u003ca href=\"\/he\/collections\/mitochondrial-renewal\"\u003eMitochondrial Renewal\u003c\/a\u003e.\u003c\/p\u003e\n\n\u003ch2\u003eWhere this sits in the catalog architecture\u003c\/h2\u003e\n\n\u003cp\u003eThe True Health Protocol catalog is organised in mechanism-first layers. Quercetin sits at the intersection of the \u003cstrong\u003eSenolytics layer\u003c\/strong\u003e (with \u003ca href=\"\/he\/products\/fisetin-500mg-senolytic-flavonoid-for-cellular-cleanup\"\u003eFisetin\u003c\/a\u003e and the spermidine \/ urolithin pair) and the \u003cstrong\u003eFoundational Health layer\u003c\/strong\u003e (next to \u003ca href=\"\/he\/products\/curcumin-1000mg-bioperine-anti-inflammatory-longevity\"\u003eCurcumin\u003c\/a\u003e as the inflammaging-control flavonoid pair, with omega-3 and vitamin D3+K2). It is also a member of the \u003cstrong\u003eBrain \u0026amp; Cognitive Longevity\u003c\/strong\u003e stack (BBB-permeable flavonoid, Howitz 2003 SIRT1) and the \u003cstrong\u003eCardiovascular Longevity\u003c\/strong\u003e stack (Edwards 2007 \/ Brüll 2017). For the canonical reading list see \u003ca href=\"\/he\/blogs\/news\/senolytics-how-to-clear-zombie-cells-with-fisetin-quercetin-and-apigenin\"\u003eSenolytics: How to Clear Zombie Cells with Fisetin, Quercetin, and Apigenin\u003c\/a\u003e and \u003ca href=\"\/he\/blogs\/news\/foundational-health-the-7-daily-nutrients-that-run-underneath-every-longevity-stack\"\u003eFoundational Health: The 7 Daily Nutrients\u003c\/a\u003e.\u003c\/p\u003e\n\n\u003ch2\u003eWhy 500 mg specifically — the dose-response curve\u003c\/h2\u003e\n\n\u003cp\u003eThe published quercetin-dose response is roughly four-tier:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u0026lt; 100 mg\/day\u003c\/strong\u003e — sub-clinical for most measured endpoints, even with a piperine vehicle. This is roughly what a high-quercetin diet (red onion, capers, apple skins, green tea) delivers; it contributes but does not replace supplementation for the human-trialed effects.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e150–500 mg\/day\u003c\/strong\u003e — the daily-cardiovascular \/ allergy \/ inflammation band. Edwards 2007 (730 mg\/day, BP), Egert 2009 (150 mg\/day, BP\/oxLDL), Pfeuffer 2013 (150 mg\/day, TNF-α), Brüll 2017 (162 mg\/day, ambulatory BP), Yamada 2022 (200 mg\/day EMIQ, allergy). One capsule a day = the upper end of this band, with the BioPerine bioavailability boost.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e1,000 mg\/day on hit-days\u003c\/strong\u003e — the Justice 2019 \/ Hickson 2019 senolytic dose. Two capsules of this product on day 1 and day 2 (and optionally day 3) of a senolytic pulse, then back to baseline for 4–12 weeks. This is also the Knab 2011 endurance-trial dose.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e\u0026gt; 1,500 mg\/day chronic\u003c\/strong\u003e — clinical-supervision tier. Studied at up to 5 g\/day for short courses (Harwood 2007 safety review) but offers no documented benefit-curve advantage over the 500–1,000 mg daily tier and increases the chance of GI tolerance issues and CYP-interaction relevance.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhat to expect — week by week\u003c\/h2\u003e\n\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDay 1–7.\u003c\/strong\u003e Nothing visible. Plasma quercetin peaks at 2–4 hours and clears 16–24 hours; with BioPerine the AUC is ~20× higher than aglycone alone (Khan 2014). Mast-cell membrane loading takes weeks, not days — do not expect immediate antihistamine effect.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeek 2–4.\u003c\/strong\u003e First subjective shifts in people targeting allergy\/histamine: less reactive nasal mucosa, lower itch threshold (Mlcek 2016, Yamada 2022 timeline). For inflammatory markers, hsCRP movement begins (Pfeuffer 2013).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeek 4–8.\u003c\/strong\u003e The Edwards 2007 \/ Brüll 2017 ambulatory-BP signal window. People targeting BP should re-measure cuff readings at this point. Egert 2009 oxidised-LDL endpoint also lands here.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeek 6–12.\u003c\/strong\u003e The \"compound is doing its job in the background\" tier — TNF-α \/ IL-6 \/ hsCRP modestly down, postprandial-glucose curve smoother, allergy symptoms quieter through the season. Senolytic protocols started in this window typically run their first hit-pulse at week 8–12.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSenolytic hit-days (whenever scheduled).\u003c\/strong\u003e At the 2× 500 mg dose, no acute subjective shift is typical. Some people report a 1–3 day \"tired-and-clean\" feeling 24–72 hours after the pulse; this is described in the Mayo write-ups as plausible SASP-clearance \/ acute-immune reset, not as a clinical endpoint.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMonth 3–6.\u003c\/strong\u003e Cardiovascular and inflammation tiers stable. If running quarterly senolytic pulses, this is also the cadence the Mayo investigators have publicly described in lay interviews.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOn stop:\u003c\/strong\u003e Plasma quercetin clears in 24–72 hours; mast-cell stabilisation effect fades over 2–4 weeks; senolytic clearance benefits persist as long as the cleared cells stay cleared (i.e. do not start the senolytic pulse if you intend to stop after a single round — the cadence is the protocol).\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eDaily protocol and senolytic-pulse protocol\u003c\/h2\u003e\n\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDaily-flavonoid protocol.\u003c\/strong\u003e 1 capsule (500 mg) per day, with food (a small amount of fat aids absorption alongside the BioPerine), morning, continuous for 8–12 weeks before evaluating. Stack with Curcumin and Omega-3 in the same dose.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSenolytic-pulse protocol (over-the-counter Mayo-style).\u003c\/strong\u003e 2 capsules (1,000 mg) per day on day 1 and day 2 (optionally day 3), with food. Run paired with Fisetin 500mg at 2,000 mg fisetin\/day on the same days. Repeat every 4–12 weeks. Most catalog users run quarterly pulses.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAllergy-season pre-load.\u003c\/strong\u003e 1 capsule daily starting 4–6 weeks before known seasonal trigger, continuing through the season. Pair with vitamin C (1,000 mg\/day, liposomal preferred) and an antihistamine if your clinician has prescribed one.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWhat \"with food\" means.\u003c\/strong\u003e A meal containing a small amount of fat (eggs, avocado, nuts, oil dressing). Quercetin and piperine are both better absorbed with fat, and BioPerine is the documented bioavailability vector.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBottle math.\u003c\/strong\u003e 60 capsules = 60 days at the daily-flavonoid dose, or about 10 senolytic pulses at 6 capsules per pulse, or one season of daily allergy pre-load.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCommon mistakes to avoid\u003c\/h2\u003e\n\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBuying a 95% rutin \/ \"bioflavonoid complex\" and assuming it's equivalent.\u003c\/strong\u003e Rutin and hesperidin are not quercetin — they convert to small fractions of quercetin in the gut. The published trials use either quercetin aglycone, quercetin dihydrate, or EMIQ. This product specifies ≥ 98% quercetin dihydrate by HPLC.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSkipping the BioPerine.\u003c\/strong\u003e Aglycone quercetin alone is ~ 1–2% bioavailable. Piperine pushes that ~20× (Khan 2014). A \"quercetin only\" capsule sold cheaply is likely missing the vector that makes the dose actually land — you would need ~5,000+ mg of unenhanced aglycone to match what 500 mg + piperine delivers.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStopping after one senolytic pulse.\u003c\/strong\u003e The Mayo data is built around recurring pulses. A single 2-day pulse with no follow-up does not reproduce the trial protocol.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRunning quercetin and fisetin on the same day for senolytics.\u003c\/strong\u003e The published over-the-counter senolytic stacks alternate the two flavonoids in adjacent pulses (e.g. quercetin + dasatinib in pulse 1, fisetin alone in pulse 2). Same-day double-flavonoid stacking is not the published protocol.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTreating quercetin as an acute antihistamine like an OTC drug.\u003c\/strong\u003e Quercetin is a mast-cell stabiliser — it loads over 2–4 weeks. People who try it acutely during a histamine flare and conclude \"it doesn't work\" are using it as if it were cetirizine; mechanism mismatch.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStacking quercetin with a CYP3A4-narrow-therapeutic-index drug without checking.\u003c\/strong\u003e Quercetin inhibits CYP3A4 and CYP2C9 in vitro and at high doses. If you're on warfarin, ciclosporin, tacrolimus, sirolimus, or a tyrosine-kinase inhibitor (e.g. dasatinib, erlotinib) prescribed on its own, talk to your prescriber before stacking.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEmpty-stomach dosing.\u003c\/strong\u003e Both quercetin and piperine absorb materially better with food; empty-stomach dosing leaves bioavailability on the table.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWho this is for\u003c\/h2\u003e\n\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eAdults running a longevity protocol\u003c\/strong\u003e who want the senolytic and the foundational-anti-inflammatory layer in the same molecule.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAdults 40+\u003c\/strong\u003e with creeping hsCRP, ambulatory-BP drift, or a family history of cardiovascular disease, who want a flavonoid layer alongside their omega-3 \/ curcumin \/ D3+K2 base.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePeople with seasonal allergic rhinitis or exercise-induced bronchospasm\u003c\/strong\u003e who want to load a mast-cell stabiliser before the season vs. relying on acute antihistamines alone.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNMN \/ Resveratrol \/ NAD+ stack users\u003c\/strong\u003e who want the senolytic flank to clear the same cells the NAD+ pool is trying to fuel.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEndurance athletes\u003c\/strong\u003e running the Knab 2011 \/ Davis 2009 mitochondrial-biogenesis protocol.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVegan \/ vegetarian users\u003c\/strong\u003e — capsule is HPMC, no animal-sourced excipients.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWho this is NOT for\u003c\/h2\u003e\n\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePeople on a tyrosine-kinase inhibitor (dasatinib, imatinib, erlotinib, etc.) without their oncologist's involvement.\u003c\/strong\u003e The Mayo D+Q protocol uses dasatinib at a deliberately chosen senolytic dose under medical supervision — DIY-ing TKI dosing is not the same protocol.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePeople on warfarin or other CYP3A4 \/ CYP2C9-narrow-therapeutic-index drugs\u003c\/strong\u003e who haven't checked with their prescriber. Quercetin inhibits these enzymes at high chronic doses and BioPerine modestly inhibits CYP3A4 too.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePregnant or breastfeeding women\u003c\/strong\u003e — the dataset is too thin to recommend; safety has not been established for senolytic-tier doses in pregnancy.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eChildren under 18\u003c\/strong\u003e — no pediatric dose-finding data.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAnyone scheduled for surgery within 2 weeks\u003c\/strong\u003e — quercetin has mild antiplatelet activity in vitro; standard pre-operative supplement-pause guidance applies.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePeople allergic to plants in the Solanaceae or piperaceae families\u003c\/strong\u003e — clinically rare with quercetin itself, but BioPerine is piperine from black pepper.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePeople expecting an OTC antihistamine effect in the first 24 hours.\u003c\/strong\u003e Mechanism mismatch — see above.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eSafety, interactions and tolerance\u003c\/h2\u003e\n\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eAnticoagulants (warfarin, DOACs).\u003c\/strong\u003e Quercetin has mild antiplatelet activity in vitro and can compete with CYP2C9 metabolism of warfarin. Talk to your prescriber before stacking; the safe-default is a 2-week stop before any planned surgery.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCYP3A4-narrow-therapeutic-index drugs.\u003c\/strong\u003e Includes ciclosporin, tacrolimus, sirolimus, certain statins (simvastatin, lovastatin), some calcium-channel blockers, and several oncology TKIs. Quercetin and piperine both modulate CYP3A4 at the doses studied. Check with your prescriber.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDiabetes medications.\u003c\/strong\u003e Quercetin modestly improves insulin sensitivity (Pfeuffer 2013, Brüll 2017). If you are on insulin or sulfonylureas, monitor glucose during the first 4–6 weeks.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIron supplements.\u003c\/strong\u003e Quercetin chelates iron in vitro. Separate iron and quercetin doses by at least 4 hours.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRenal function.\u003c\/strong\u003e The Justice 2019 \/ Hickson 2019 trials enrolled adults with established renal disease at the senolytic dose with no renal AE signal — but those trials were short and supervised. People with moderate-to-severe CKD running daily quercetin should have eGFR monitored on the same cadence as their underlying disease.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGI tolerance.\u003c\/strong\u003e Headache, mild nausea, or tingling at high acute doses (≥ 1,500 mg single dose) is the most common AE in the literature. Splitting the dose across the day or moving it from empty-stomach to with-food usually resolves it.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDocumented chronic-safety ceiling.\u003c\/strong\u003e Harwood 2007 safety review: no SAE in studies up to 1 g\/day chronic and 5 g\/day for short courses. The dose this product targets is well within that band.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003ePer-capsule ingredient panel\u003c\/h2\u003e\n\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eQuercetin dihydrate (≥ 98% by HPLC):\u003c\/strong\u003e 500 mg per capsule (= ~466 mg quercetin aglycone equivalent).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBioPerine®\u003c\/strong\u003e (Piper nigrum fruit extract, std 95% piperine): 5 mg per capsule.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOther ingredients:\u003c\/strong\u003e HPMC (vegan vegetable capsule), microcrystalline cellulose, vegetable magnesium stearate.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFree of:\u003c\/strong\u003e titanium dioxide, artificial colors, artificial flavors, GMOs, gluten, soy, dairy, eggs, peanuts, tree nuts, fish, shellfish.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBottle:\u003c\/strong\u003e 60 capsules in a UV-protective amber HDPE bottle with induction-sealed cap. 60-day supply at the daily-flavonoid dose; ~10 hit-pulses at the senolytic dose.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVariant SKU:\u003c\/strong\u003e THP-QUERCETIN-500-60.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eSourcing, manufacturing \u0026amp; QC\u003c\/h2\u003e\n\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eQuercetin source:\u003c\/strong\u003e Sophora japonica (Japanese pagoda tree) flower-bud extract, the standard high-purity botanical source for HPLC-grade quercetin used by the published trials. ≥ 98% quercetin dihydrate per batch by HPLC.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBioPerine®:\u003c\/strong\u003e branded piperine from Sabinsa (the same standardised piperine used in the bioavailability literature, including Khan 2014).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturing:\u003c\/strong\u003e cGMP-certified, ISO 9001 facility, FDA-registered, made in the USA.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePer-batch testing:\u003c\/strong\u003e HPLC for quercetin assay (≥ 98%), HPLC for piperine assay (≥ 95%), USP \u0026lt;2232\u0026gt; heavy metals (As\/Cd\/Hg\/Pb), USP \u0026lt;2021\/2022\u0026gt; microbial (total aerobic, yeast\/mold, E. coli, Salmonella), USP \u0026lt;467\u0026gt; residual solvents, USP \u0026lt;561\u0026gt; pesticide screen.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStability:\u003c\/strong\u003e 24-month shelf life from manufacture under standard storage (cool, dry, \u0026lt; 25°C, low light).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCOA on request:\u003c\/strong\u003e available from \u003ca href=\"\/he\/pages\/quality\"\u003eour Quality \u0026amp; Testing page\u003c\/a\u003e — request the lot number on the bottle base.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eFAQ\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eIs this the same dose used in the Mayo Clinic D+Q senolytic trials?\u003c\/strong\u003e Two capsules of this product (1,000 mg quercetin) on day 1 and day 2 matches the quercetin-arm dose used in Justice 2019 (\u003cem\u003eEBioMedicine\u003c\/em\u003e, IPF) and Hickson 2019 (\u003cem\u003eEBioMedicine\u003c\/em\u003e, diabetic kidney disease). The Mayo trials add prescription dasatinib 100 mg\/day on the same days; we don't sell dasatinib and don't suggest you self-prescribe it. The over-the-counter analogue replaces dasatinib with fisetin in alternating pulses.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhat's the difference between quercetin and fisetin? Should I take both?\u003c\/strong\u003e Both are flavonoids, both screen as senolytics on the SCAP map. Fisetin (Yousefzadeh 2018) was identified as a more selective senolytic than quercetin in the Mayo screen, with a slightly different selectivity profile across tissue types. The published over-the-counter senolytic strategies generally alternate them — not co-dose them on the same day. Most catalog users run quercetin + dasatinib-replacement protocols and fisetin solo protocols on alternating quarterly pulses.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhy 500 mg instead of 1,000 mg per capsule?\u003c\/strong\u003e 500 mg is the daily-flavonoid dose. Two capsules give the senolytic dose. One bottle then serves both protocols and lets the user step-up or step-down without switching SKU. 1,000 mg per capsule would force daily users to split capsules.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhy BioPerine instead of liposomal or phytosome?\u003c\/strong\u003e Phytosome (Quercefit®) and liposomal forms are also valid bioavailability strategies — they hit ~20× and ~10–30× respectively. We chose dihydrate + BioPerine because it is the dose-form best matched to the published cardiovascular and senolytic trials and is materially less expensive per mg-quercetin than the premium phytosome forms. Khan 2014 is the head-to-head reference.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eCan I open the capsule and mix it into water or juice?\u003c\/strong\u003e Yes. Quercetin is poorly water-soluble, so it will not fully dissolve, but suspending it in a fatty or oily liquid (e.g. a smoothie with avocado or nut butter) is fine and preserves the BioPerine vehicle. Heat above ~ 60°C degrades quercetin — don't add it to hot drinks.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eWill quercetin make me drowsy like an OTC antihistamine?\u003c\/strong\u003e No. Quercetin doesn't cross the blood-brain barrier the way first-generation antihistamines (diphenhydramine) do, and it doesn't bind central H1 receptors. Drowsiness is not a documented quercetin AE.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eWill it interact with my second-generation antihistamine (cetirizine, loratadine, fexofenadine)?\u003c\/strong\u003e No documented interaction. Many users layer quercetin on top of their daily antihistamine specifically because the mechanisms are upstream-vs-downstream of the same axis.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eShould I cycle off quercetin?\u003c\/strong\u003e The daily-flavonoid use case has no published rationale for cycling — most users run it continuously. The senolytic-pulse use case is inherently cyclic (4–12 week intervals between pulses). Don't run senolytic-tier doses (1,000 mg\/day) chronically; the published protocol is intermittent.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhy is \"quercetin + zinc\" so common in COVID-era stacks?\u003c\/strong\u003e Quercetin is a zinc ionophore — it transports zinc across cell membranes. Saeedi-Boroujeni 2021, Pawar 2022 and Di Pierro 2021 all describe early-treatment quercetin + zinc combinations with reduced symptom-day burden in early infection. We make no clinical claim here; this is mechanistic background.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhy isn't this in your Senolytics collection if it's a senolytic?\u003c\/strong\u003e It is. Browse \u003ca href=\"\/he\/collections\/senolytics\"\u003e\/collections\/senolytics\u003c\/a\u003e. Quercetin is also tagged into Foundational Health, Antioxidants, Cardiovascular Longevity and Brain \u0026amp; Cognitive Longevity — that's the mechanism-overlap point: quercetin spans more than one layer.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eCan I take it with other supplements in my morning stack?\u003c\/strong\u003e Yes — quercetin pairs natively with curcumin, resveratrol, NMN, fisetin, omega-3, vitamin C, and the antioxidant flank (NAC, glutathione). The two timing notes: (1) separate iron supplements by 4 hours, (2) take all of these with food and a small amount of fat for best absorption.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eWill it lower my blood pressure too much if I'm already on a BP medication?\u003c\/strong\u003e Probably not — the magnitude of quercetin's BP effect is modest (3–7 mmHg in hypertensive subgroups; no effect in already-controlled BP, Edwards 2007). But measure cuff readings during the first 4–6 weeks if you're already on a BP med, and tell your prescriber.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhy is the bottle plastic and not glass?\u003c\/strong\u003e Amber HDPE blocks UV (the relevant degradation vector for quercetin) at parity with amber glass and avoids the breakage and weight cost. The bottle is recyclable resin #2.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhat happens if I miss a daily dose?\u003c\/strong\u003e No catch-up needed. Plasma quercetin is short-lived and the daily-flavonoid effects are cumulative over weeks — a missed day is a missed day. Just resume at the next planned dose.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eIs the source vegan and GMO-free?\u003c\/strong\u003e Yes. Quercetin is from \u003cem\u003eSophora japonica\u003c\/em\u003e flower-bud extract; BioPerine® is from \u003cem\u003ePiper nigrum\u003c\/em\u003e fruit extract; the capsule is HPMC. No animal-derived ingredients, no GMO inputs.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eCan I take it during a fasted state for autophagy enhancement?\u003c\/strong\u003e You can — quercetin AMPK activation is part of the autophagy story (Ahn 2008) — but absorption is materially better with food and the BioPerine vehicle. If you're running fasted protocols, take the capsule at the first meal of the day.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eDoes it have any taste or smell?\u003c\/strong\u003e Quercetin is bright yellow with a mild bitter note. The capsule masks both. Opening the capsule produces a yellow powder that will stain fabric — handle the same way you would turmeric.\u003c\/p\u003e\n\n\u003ch2\u003eWhy not Amazon\u003c\/h2\u003e\n\n\u003cp\u003eThree things separate this bottle from the cheapest yellow-bottle Amazon equivalent:\u003c\/p\u003e\n\u003col\u003e\n\u003cli\u003e\n\u003cstrong\u003eHPLC-verified ≥ 98% quercetin dihydrate per batch.\u003c\/strong\u003e Most market quercetin is sold against a \"95% rutin-derived\" spec, which is not the molecule used in the Justice 2019 \/ Hickson 2019 \/ Edwards 2007 trials. We test every batch for the actual quercetin assay; COA available on request.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBranded BioPerine® from Sabinsa\u003c\/strong\u003e — the same piperine used in Khan 2014's bioavailability work, not generic black-pepper extract sold as \"piperine\".\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMechanism-first catalog architecture.\u003c\/strong\u003e Quercetin sits inside the senolytics + foundational layer with all of its native pairings (Fisetin, Curcumin, Resveratrol, NMN, Urolithin A, Spermidine, Omega-3, Vitamin C) on the same site, audited together, with internal links that surface the published protocols rather than pure-play SEO.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch2\u003eRead more on the science\u003c\/h2\u003e\n\n\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"\/he\/blogs\/news\/senolytics-how-to-clear-zombie-cells-with-fisetin-quercetin-and-apigenin\"\u003eSenolytics: How to Clear Zombie Cells with Fisetin, Quercetin, and Apigenin\u003c\/a\u003e — the cornerstone catalog explainer covering the Mayo D+Q protocol, fisetin and apigenin layering, and pulse cadence.\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/he\/blogs\/news\/foundational-health-the-7-daily-nutrients-that-run-underneath-every-longevity-stack\"\u003eFoundational Health: The 7 Daily Nutrients\u003c\/a\u003e — where the curcumin + quercetin foundational-flavonoid pairing fits inside the daily 7-nutrient floor.\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/he\/blogs\/news\/how-to-stack-longevity-supplements-a-practical-protocol-for-2026\"\u003eHow to Stack Longevity Supplements: A Practical Protocol for 2026\u003c\/a\u003e — the NMN + Resveratrol + Quercetin Sinclair-style stack written out with sources.\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/he\/pages\/protocols\"\u003eProtocols page\u003c\/a\u003e — daily \/ weekly \/ pulse-cadence templates including the senolytic D+Q-style pulse.\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/he\/pages\/our-science\"\u003eOur Science\u003c\/a\u003e — the literature index this catalog is built around.\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"\/he\/pages\/quality\"\u003eQuality \u0026amp; Testing\u003c\/a\u003e — the per-batch HPLC and USP-test stack, COA-on-request workflow.\u003c\/li\u003e\n\u003cli\u003eBrowse: \u003ca href=\"\/he\/collections\/senolytics\"\u003eSenolytics\u003c\/a\u003e · \u003ca href=\"\/he\/collections\/foundational-health\"\u003eFoundational Health\u003c\/a\u003e · \u003ca href=\"\/he\/collections\/antioxidants\"\u003eAntioxidants\u003c\/a\u003e · \u003ca href=\"\/he\/collections\/cardiovascular-longevity\"\u003eCardiovascular Longevity\u003c\/a\u003e · \u003ca href=\"\/he\/collections\/brain-cognitive-longevity\"\u003eBrain \u0026amp; Cognitive Longevity\u003c\/a\u003e · \u003ca href=\"\/he\/collections\/mitochondrial-renewal\"\u003eMitochondrial Renewal\u003c\/a\u003e.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eSelected references\u003c\/h2\u003e\n\n\u003col\u003e\n\u003cli\u003eZhu Y, Tchkonia T, Pirtskhalava T, et al. The Achilles' heel of senescent cells: from transcriptome to senolytic drugs. \u003cem\u003eAging Cell\u003c\/em\u003e. 2015;14(4):644–658.\u003c\/li\u003e\n\u003cli\u003eXu M, Pirtskhalava T, Farr JN, et al. Senolytics improve physical function and increase lifespan in old age. \u003cem\u003eNat Med\u003c\/em\u003e. 2018;24(8):1246–1256.\u003c\/li\u003e\n\u003cli\u003eJustice JN, Nambiar AM, Tchkonia T, et al. Senolytics in idiopathic pulmonary fibrosis: results from a first-in-human, open-label, pilot study. \u003cem\u003eEBioMedicine\u003c\/em\u003e. 2019;40:554–563.\u003c\/li\u003e\n\u003cli\u003eHickson LJ, Langhi Prata LGP, Bobart SA, et al. Senolytics decrease senescent cells in humans: preliminary report from a clinical trial of dasatinib plus quercetin in individuals with diabetic kidney disease. \u003cem\u003eEBioMedicine\u003c\/em\u003e. 2019;47:446–456.\u003c\/li\u003e\n\u003cli\u003eYousefzadeh MJ, Zhu Y, McGowan SJ, et al. Fisetin is a senotherapeutic that extends health and lifespan. \u003cem\u003eEBioMedicine\u003c\/em\u003e. 2018;36:18–28.\u003c\/li\u003e\n\u003cli\u003ePearce FL, Befus AD, Bienenstock J. Mucosal mast cells. III. Effect of quercetin and other flavonoids on antigen-induced histamine secretion. \u003cem\u003eJ Allergy Clin Immunol\u003c\/em\u003e. 1984;73(6):819–823.\u003c\/li\u003e\n\u003cli\u003eMlcek J, Jurikova T, Skrovankova S, Sochor J. Quercetin and its anti-allergic immune response. \u003cem\u003eMolecules\u003c\/em\u003e. 2016;21(5):623.\u003c\/li\u003e\n\u003cli\u003eEndale M, Park SC, Kim S, et al. Quercetin disrupts tyrosine-phosphorylated PI3K and MAPK pathways and inhibits NF-κB activation. \u003cem\u003eImmunobiology\u003c\/em\u003e. 2013;218(12):1452–1467.\u003c\/li\u003e\n\u003cli\u003eEdwards RL, Lyon T, Litwin SE, et al. Quercetin reduces blood pressure in hypertensive subjects. \u003cem\u003eJ Nutr\u003c\/em\u003e. 2007;137(11):2405–2411.\u003c\/li\u003e\n\u003cli\u003eEgert S, Bosy-Westphal A, Seiberl J, et al. Quercetin reduces systolic blood pressure and plasma oxidised low-density lipoprotein concentrations in overweight subjects with a high-cardiovascular-disease-risk phenotype. \u003cem\u003eBr J Nutr\u003c\/em\u003e. 2009;102(7):1065–1074.\u003c\/li\u003e\n\u003cli\u003ePfeuffer M, Auinger A, Bley U, et al. Effect of quercetin on traits of the metabolic syndrome, endothelial function and inflammation in men with different ApoE isoforms. \u003cem\u003eMol Nutr Food Res\u003c\/em\u003e. 2013;57(7):1117–1125.\u003c\/li\u003e\n\u003cli\u003eBrüll V, Burak C, Stoffel-Wagner B, et al. Effects of a quercetin-rich onion-skin extract on 24-hour ambulatory blood pressure and endothelial function in overweight-to-obese hypertensive patients. \u003cem\u003eBr J Nutr\u003c\/em\u003e. 2017;117(3):403–414.\u003c\/li\u003e\n\u003cli\u003eYamada S, Shirai M, Inaba Y, Takara T. Effects of repeated oral intake of a quercetin-containing supplement on allergic reaction. \u003cem\u003eFood Sci Biotechnol\u003c\/em\u003e. 2022;31(13):1623–1633.\u003c\/li\u003e\n\u003cli\u003eJafarinia M, Sadat Hosseini M, Kasiri N, et al. Quercetin with the potential effect on allergic diseases. \u003cem\u003eAllergy Asthma Clin Immunol\u003c\/em\u003e. 2020;16:36.\u003c\/li\u003e\n\u003cli\u003eKhan WA, Patel N, et al. Effect of co-administration of piperine on pharmacokinetics of quercetin in rats. \u003cem\u003ePhytother Res\u003c\/em\u003e. 2014.\u003c\/li\u003e\n\u003cli\u003eKnab AM, Shanely RA, Henson DA, et al. Influence of quercetin supplementation on disease risk factors in community-dwelling adults. \u003cem\u003eMed Sci Sports Exerc\u003c\/em\u003e. 2011;43(10):1795–1801.\u003c\/li\u003e\n\u003cli\u003eHowitz KT, Bitterman KJ, Cohen HY, et al. Small molecule activators of sirtuins extend Saccharomyces cerevisiae lifespan. \u003cem\u003eNature\u003c\/em\u003e. 2003;425(6954):191–196.\u003c\/li\u003e\n\u003cli\u003eAhn J, Lee H, Kim S, et al. The anti-obesity effect of quercetin is mediated by the AMPK and MAPK signaling pathways. \u003cem\u003eBiochem Biophys Res Commun\u003c\/em\u003e. 2008;373(4):545–549.\u003c\/li\u003e\n\u003cli\u003eHarwood M, Danielewska-Nikiel B, Borzelleca JF, et al. A critical review of the data related to the safety of quercetin and lack of evidence of in vivo toxicity. \u003cem\u003eFood Chem Toxicol\u003c\/em\u003e. 2007;45(11):2179–2205.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003cp\u003e\u003cem\u003eReferences cited as scientific context, not endorsement of any product. Statements have not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease. Consult your healthcare provider before starting any supplement, particularly if you are pregnant, nursing, taking prescription medications, or planning surgery.\u003c\/em\u003e\u003c\/p\u003e\n\n\u003cp\u003eHave a question? \u003ca href=\"mailto:support@truehealthprotocol.health\"\u003esupport@truehealthprotocol.health\u003c\/a\u003e\u003c\/p\u003e\n","brand":"True Health Protocol","offers":[{"title":"Default Title","offer_id":47839101059290,"sku":"THP-QUERCETIN-500-60","price":29.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0814\/5158\/1658\/files\/thp_quercetin.png?v=1778047684","url":"https:\/\/truehealthprotocol.health\/he\/products\/quercetin-500mg-senolytic-flavonoid-natural-antihistamine","provider":"True Health Protocol","version":"1.0","type":"link"}