Quercetin
19 benefits mapped to clinical evidence across supplements.
Dose per serving from products
2,084 products in our catalogue print how much Quercetin a serving holds.
Most common: 25 mg to 50 mg, 19% of 2,084 products.
| Dose per serving | Products |
|---|---|
| 5 mg or less | 103 |
| 5 mg to 10 mg | 81 |
| 10 mg to 25 mg | 299 |
| 25 mg to 50 mg | 394 |
| 50 mg to 100 mg | 294 |
| 100 mg to 250 mg | 328 |
| 250 mg to 500 mg | 353 |
| 500 mg to 1 g | 203 |
| over 1 g | 29 |
Dose per serving from research
97 study groups in 75 studies say how much Quercetin participants took a day.
These are the doses the studies gave. They are not a recommendation.
Most common: 500 mg to 1 g, 28% of 97 study groups.
| Daily dose | Study groups |
|---|---|
| 25 mg or less | 4 |
| 25 mg to 50 mg | 5 |
| 50 mg to 100 mg | 6 |
| 100 mg to 250 mg | 25 |
| 250 mg to 500 mg | 23 |
| 500 mg to 1 g | 27 |
| 1 g to 2.5 g | 7 |
Commonly used together
27 of 100 study groups took Quercetin with something else. Shown: what 3 or more different studies gave.
What was given together, not what works together.
| Taken with | Study groups |
|---|---|
| Vitamin C | 14 |
| Niacin | 5 |
| Green Tea Extract | 4 |
| Vitamin D | 3 |
Benefit Evidence
Lipids down: LDL/TC
Blood pressure/endothelial function up
Arrhythmia/ischemia reduced
Bone markers +2.7%
Inflammation/vascular aging
NAFLD liver fat â1.9%
less soreness, â5.5%
faster strength recovery, â10pp
better endurance, +3.9%
Respiratory relief, +symptoms
Faster lung recovery, inflammation
Fewer URTIs, allergies
Lipids down: LDL/TC
Blood pressure/endothelial function up
Arrhythmia/ischemia reduced
less soreness, â5.5%
faster strength recovery, â10pp
better endurance, +3.9%
Respiratory relief, +symptoms
Faster lung recovery, inflammation
Fewer URTIs, allergies
Research sources
Heart health (16)
- Effect of quercetin on parameters of central hemodynamics and myocardial ischemia in patients with stable coronary heart disease
PubMed ID: 29064791
Small RCT in stable coronary disease showed reduced PVCs and ischemic episodes and improved diastolic measures with 120 mg/dayâdirect cardiac benefit.
- Epicatechin and quercetin exhibit in vitro antioxidant effect, improve biochemical parameters related to metabolic syndrome, and decrease cellular genotoxicity in humans
PubMed ID: 33773697
Combination bread lowered cholesterol, triglycerides and fasting glucoseâlipid and metabolic improvements supportive of heart health.
- Concentrated red grape juice exerts antioxidant, hypolipidemic, and antiinflammatory effects in both hemodialysis patients and healthy subjects
PubMed ID: 16825703
Concentrated red grape juice (polyphenols incl. quercetin) improved cholesterol profile and reduced oxidized LDL and inflammation markers.
- Quercetin reduces blood pressure in hypertensive subjects
PubMed ID: 17951477
Randomized crossover: quercetin lowered systolic/diastolic BP ~5â7 mmHg in stage 1 hypertensives (clinically meaningful).
- Effect of quercetin on traits of the metabolic syndrome, endothelial function and inflammation in men with different APOE isoforms
PubMed ID: 22118955
150 mg/day reduced postprandial triacylglycerol and increased HDL in men â direct cardiometabolic signal.
- Quercetin in the treatment of dyslipidemia
PubMed ID: 22486135
Large randomized study reported substantial reductions in total and LDL cholesterol and increased HDL in dyslipidemia â strong cardio-relevant result (moderate confidence).
- Supplementation of the Pure Flavonoids Epicatechin and Quercetin Affects Some Biomarkers of Endothelial Dysfunction and Inflammation in (Pre)Hypertensive Adults: A Randomized Double-Blind, Placebo-Controlled, Crossover Trial
PubMed ID: 25972527
Quercetin-3-glucoside reduced sE-selectin (endothelial activation) in (pre)hypertensives â supports vascular/heart benefit.
- Effects of a quercetin-rich onion skin extract on 24 h ambulatory blood pressure and endothelial function in overweight-to-obese patients with (pre-)hypertension: a randomised double-blinded placebo-controlled cross-over trial
PubMed ID: 26328470
162 mg/day quercetin modestly lowered 24 h systolic BP in hypertensive subgroupâclinically relevant heart/cardiovascular support in that subgroup.
- Effect of onion peel extract on endothelial function and endothelial progenitor cells in overweight and obese individuals
PubMed ID: 26233871
100 mg/day onion peel extract improved flow-mediated dilation and increased endothelial progenitor cellsâcardiovascular-supportive effects.
- Targeting protein disulfide isomerase with the flavonoid isoquercetin to improve hypercoagulability in advanced cancer
PubMed ID: 30652973
Isoquercetin reduced hypercoagulability biomarkers (D-dimer, thrombin generation) in cancer patientsârelevant to thrombotic risk and cardiovascular support.
- Quercetin Reduces Vascular Senescence and Inflammation in Symptomatic Male but Not Female Coronary Artery Disease Patients
PubMed ID: 40375481
Quercetin improved endotheliumâdependent relaxation (ACh EC50) and was associated with fewer postâop AF events in men (clear cardiovascular signals).
- Effectiveness and Safety of Novel Nutraceutical Formulation Added to Ezetimibe in Statin-Intolerant Hypercholesterolemic Subjects with Moderate-to-High Cardiovascular Risk
PubMed ID: 32456525
Adding a multiâingredient nutraceutical (includes quercetin) to ezetimibe produced substantially larger LDL and total cholesterol reductions â clinically meaningful cardiovascular risk effect (multiâcomponent).
- Grape polyphenols exert a cardioprotective effect in pre- and postmenopausal women by lowering plasma lipids and reducing oxidative stress
PubMed ID: 16046716
Grape polyphenol powder (contains quercetin) lowered triglycerides/LDL and reduced systemic oxidative stress â favorable lipid/oxidative profile relevant to heart health.
- Impact of quercetin in patients with myocardial infarction. A multicenter, randomized, and open-label pilot study
PubMed ID: 37567562
IV quercetin around reperfusion in STEMI reduced infarct biomarker release and intramyocardial hemorrhage â strong acute cardioprotective signal.
- Quercetin reduces systolic blood pressure and plasma oxidised low-density lipoprotein concentrations in overweight subjects with a high-cardiovascular disease risk phenotype: a double-blinded, placebo-controlled cross-over study
PubMed ID: 19402938
150 mg/day quercetin modestly lowered systolic blood pressure and decreased oxidized LDL in atârisk adults (large doubleâblind crossover).
- Polyphenolic compounds from red grapes acutely improve endothelial function in patients with coronary heart disease
PubMed ID: 16319551
Acute red grape polyphenol drink (small quercetin content) improved flow-mediated dilation (endothelial function).
Inflammation (14)
- Supplementation of the Pure Flavonoids Epicatechin and Quercetin Affects Some Biomarkers of Endothelial Dysfunction and Inflammation in (Pre)Hypertensive Adults: A Randomized Double-Blind, Placebo-Controlled, Crossover Trial
PubMed ID: 25972527
Quercetin-3-glucoside lowered IL-1ÎČ and an inflammation z-score in (pre)hypertensives â clear human anti-inflammatory biomarker effect.
- The Adjunctive Effect of Quercetin on Postoperative Pain Management Following Cesarean Section: A Randomized Controlled Study
PubMed ID: 40687903
Single 500 mg preop dose reduced postoperative pain scores and delayed rescue analgesia (clinical antiâinflammatory/analgesic effect).
- Quercetin Reduces Vascular Senescence and Inflammation in Symptomatic Male but Not Female Coronary Artery Disease Patients
PubMed ID: 40375481
Quercetin reduced hsâCRP interactions and vascular senescence markers (strong antiâinflammatory/senolytic signal in humans, sexâspecific).
- Quercetin and polycystic ovary syndrome; inflammation, hormonal parameters and pregnancy outcome: A randomized clinical trial
PubMed ID: 36317442
PCOS RCT documented significant decreases in TNFâα and ILâ6 after quercetin (direct antiâinflammatory biomarker evidence).
- The Effect of Quercetin on Inflammatory Factors and Clinical Symptoms in Women with Rheumatoid Arthritis: A Double-Blind, Randomized Controlled Trial
PubMed ID: 27710596
RA RCT (500 mg/day) reduced hsâTNFâα and clinical inflammatory symptomsâstrong human evidence of antiâinflammatory action.
- Quercetin's influence on exercise-induced changes in plasma cytokines and muscle and leukocyte cytokine mRNA
PubMed ID: 17717114
Significant reductions in leukocyte IL-8 and IL-10 mRNA after heavy exercise show a localized anti-inflammatory transcriptional effect.
- Yindan Jiedu granules exhibit anti-inflammatory effect in patients with novel Coronavirus disease (COVID-19) by suppressing the NF-ÎșB signaling pathway
PubMed ID: 34785108
Multiâherb COVID formula (contains quercetin) produced more rapid reductions in ESR and SAA and faster symptom/imaging resolution â strong antiâinflammatory signals but multiâconstituent confounding.
- The effect of quercetin on iron overload and inflammation in ÎČ-thalassemia major patients: A double-blind randomized clinical trial
PubMed ID: 31519283
Randomized trial in ÎČâthalassemia major showed a statistically significant decrease in hsâCRP (p=0.046) â direct clinical evidence of antiâinflammatory effect in that population.
- Efficacy and Safety of Topical Compound Heparin Sodium Allantoin Gel (Main Components: Onion Extract Quercetin) for the Treatment of Rosacea
PubMed ID: 40177799
Topical onion extract gel (source of quercetin) reduced rosacea erythema and TEWL and improved clinical inflammatory outcomes in RCT when combined with doxycycline.
- Comparison of clinical and histological effects between lactobacillus-fermented Chamaecyparis obtusa and tea tree oil for the treatment of acne: an eight-week double-blind randomized controlled split-face study
PubMed ID: 25228478
Fermented Chamaecyparis product with increased quercetin markedly reduced inflammatory acne lesion counts (clinical antiâinflammatory skin outcome).
- Interleukin-6 as a potential indicator for prevention of high-risk adenoma recurrence by dietary flavonols in the polyp prevention trial
PubMed ID: 20484173
Higher flavonol intake associated with lower systemic ILâ6 (populationâlevel inflammatory marker reduction).
- Quercetin in men with category III chronic prostatitis: a preliminary prospective, double-blind, placebo-controlled trial
PubMed ID: 10604689
Quercetin (500 mg BID) improved symptoms in chronic prostatitis (inflammatory pelvic pain), consistent with antiâinflammatory benefit.
- [Jianpi Zishen granule inhibits podocyte autophagy in systemic lupus erythematosus: a network pharmacology and clinical study]
PubMed ID: 38597437
Herbal formula with quercetin reduced JAK/STAT activation and autophagy markers in SLE, indicating antiâinflammatory effects (multiâcomponent).
- The therapeutic efficacy of quercetin in combination with antiviral drugs in hospitalized COVID-19 patients: A randomized controlled trial
PubMed ID: 34863994
In COVIDâ19 patients quercetin adjunct produced larger decreases in qâCRP and LDH â clinical inflammatory marker improvements.
Immune support (12)
- The therapeutic efficacy of quercetin in combination with antiviral drugs in hospitalized COVID-19 patients: A randomized controlled trial
PubMed ID: 34863994
RDB trial in hospitalized COVID-19 showed shorter stays and larger CRP/LDH reductions when quercetin was added â moderate clinical immune/inflammatory signal.
- Interleukin-6 as a potential indicator for prevention of high-risk adenoma recurrence by dietary flavonols in the polyp prevention trial
PubMed ID: 20484173
Higher dietary flavonol intake (including quercetin) associated with lower ILâ6 and reduced highârisk adenoma recurrence (inflammatory/immune marker link).
- [Jianpi Zishen granule inhibits podocyte autophagy in systemic lupus erythematosus: a network pharmacology and clinical study]
PubMed ID: 38597437
Herbal formula containing quercetin reduced JAK/STAT activation in SLE patients, indicating immuneâmodulatory effects (but multiâcomponent product).
- A Mixed Flavonoid-Fish Oil Supplement Induces Immune-Enhancing and Anti-Inflammatory Transcriptomic Changes in Adult Obese and Overweight Women-A Randomized Controlled Trial
PubMed ID: 27187447
Quercetin-containing supplement upregulated type I interferon/antiviral gene signatures and raised plasma quercetin (direct immuneârelevant transcriptomic effect).
- Immunomodulatory effects and mechanisms of Qi-Xu-Tiao-Ti formula in Qi-deficiency constitution: a randomized controlled trial integrated with multi-omics and network pharmacology analysis
PubMed ID: 41246353
Herbal formula including quercetin increased IgA and IgG in a randomized trial â direct immune markers improved but intervention was multiâcomponent.
- Quercetin reduces illness but not immune perturbations after intensive exercise
PubMed ID: 17805089
Randomized trial: large reduction in post-exercise URTI incidence with quercetin.
- The Effect of Quercetin on Inflammatory Factors and Clinical Symptoms in Women with Rheumatoid Arthritis: A Double-Blind, Randomized Controlled Trial
PubMed ID: 27710596
RA trial showed reduced inflammatory TNF-α and symptomatic improvement, suggesting immune-modulatory effects relevant to immune support.
- Effects of repeated oral intake of a quercetin-containing supplement on allergic reaction: a randomized, placebo-controlled, double-blind parallel-group study
PubMed ID: 35776034
Allergy RCT showing symptomatic improvement indicates immunomodulatory effects in pollinosis.
- Quercetin and polycystic ovary syndrome; inflammation, hormonal parameters and pregnancy outcome: A randomized clinical trial
PubMed ID: 36317442
PCOS RCT showed reductions in TNFâα and ILâ6 (direct inflammatory/immune markers).
- Characterization of Human Senescent Cell Biomarkers for Clinical Trials
PubMed ID: 39823170
Biomarkerâstratified D+Q effects on p16 (senescence/immune ageing) link to immune system regulation (indirect, combo).
- Quercetin Reduces Vascular Senescence and Inflammation in Symptomatic Male but Not Female Coronary Artery Disease Patients
PubMed ID: 40375481
Perioperative quercetin lowered hsâCRP/timeĂtreatment interactions, suggesting systemic antiâinflammatory effects.
- Yindan Jiedu granules exhibit anti-inflammatory effect in patients with novel Coronavirus disease (COVID-19) by suppressing the NF-ÎșB signaling pathway
PubMed ID: 34785108
Multiâherb COVID trial (contains quercetin) showed faster radiologic/virologic recovery and faster CD4+ count rise â suggests immune benefit but effect cannot be attributed solely to quercetin.
Metabolism (8)
- Quercetin intervention reduced hepatic fat deposition in patients with nonalcoholic fatty liver disease: a randomized, double-blind, placebo-controlled crossover clinical trial
PubMed ID: 39032786
12âweek 500 mg/day quercetin RCT produced significant reductions in intrahepatic lipid and modest weight/BMI loss (direct metabolic benefit).
- Fat reducing effects of Nelumbo nucifera leaf extract in overweight patients
PubMed ID: 34852695
Nelumbo leaf extract rich in a quercetin glucuronide reduced body fat and visceral fat in men over 12 weeksâsupports bodyâcomposition/metabolic effects.
- Quercetin and polycystic ovary syndrome; inflammation, hormonal parameters and pregnancy outcome: A randomized clinical trial
PubMed ID: 36317442
PCOS RCT lowered LH and inflammatory markers and improved reproductive outcomes â metabolic/hormonal modulation relevant to metabolic health.
- Effect of quercetin on traits of the metabolic syndrome, endothelial function and inflammation in men with different APOE isoforms
PubMed ID: 22118955
Modest decreases in waist circumference and postprandial TAG and increase in HDL indicate metabolic benefits in men at 150 mg/day.
- Quercetin in the treatment of dyslipidemia
PubMed ID: 22486135
Large dyslipidemia trial showed clinically meaningful lipid improvements â metabolic support signal.
- Effects of Quercetin on Adiponectin-Mediated Insulin Sensitivity in Polycystic Ovary Syndrome: A Randomized Placebo-Controlled Double-Blind Clinical Trial
PubMed ID: 27824398
1 g/day quercetin for 12 weeks in PCOS improved adiponectin and HOMAâIR and reduced testosteroneâstrong metabolic improvements.
- The effects of quercetin supplementation on metabolic and hormonal parameters as well as plasma concentration and gene expression of resistin in overweight or obese women with polycystic ovary syndrome
PubMed ID: 30062709
1 g/day quercetin in overweight/obese PCOS women markedly reduced resistin (plasma and mRNA) and modestly improved hormonesâsupports metabolic modulation.
- Epicatechin and quercetin exhibit in vitro antioxidant effect, improve biochemical parameters related to metabolic syndrome, and decrease cellular genotoxicity in humans
PubMed ID: 33773697
Three-month RCT with quercetin+epicatechin enriched bread improved lipids and fasting glucose in metabolicârisk participantsârobust metabolic benefit (combination product).
Antioxidant (9)
- Effects of quercetin supplementation on inflammatory factors and quality of life in post-myocardial infarction patients: A double blind, placebo-controlled, randomized clinical trial
PubMed ID: 33216421
500 mg/day quercetin after MI increased total antioxidant capacity significantlyâdirect antioxidant endpoint in humans.
- Circadian Modulation of the Antioxidant Effect of Grape Consumption: A Randomized Controlled Trial
PubMed ID: 37569042
Grape drink (contains quercetin) reduced postâmeal F2âisoprostane (oxidative stress) with urinary quercetin rises â supports antioxidant activity in humans.
- Impact of multiple genetic polymorphisms on effects of a 4-week blueberry juice intervention on ex vivo induced lymphocytic DNA damage in human volunteers
PubMed ID: 17602170
Intervention increased plasma quercetin and produced ~20% protection against H2O2-provoked oxidative DNA damage.
- Effects of enzymatically modified isoquercitrin in supplementary protein powder on athlete body composition: a randomized, placebo-controlled, double-blind trial
PubMed ID: 31500646
EMIQ plus protein increased antioxidant index (BAP/d-ROMs) in athletesâevidence of improved systemic antioxidant status.
- Consumption of black currants, lingonberries and bilberries increases serum quercetin concentrations
PubMed ID: 12548295
Daily berry consumption substantially increased serum quercetin and intake, supporting in vivo antioxidant exposure.
- Grape polyphenols exert a cardioprotective effect in pre- and postmenopausal women by lowering plasma lipids and reducing oxidative stress
PubMed ID: 16046716
Grape polyphenol product including quercetin reduced urinary F2âisoprostanes (marker of wholeâbody oxidative stress) in women â clinical antioxidant marker improvement (multiâcomponent).
- Concentrated red grape juice exerts antioxidant, hypolipidemic, and antiinflammatory effects in both hemodialysis patients and healthy subjects
PubMed ID: 16825703
Red grape juice (polyphenols incl. quercetin) reduced oxidized LDL and improved antioxidant markers.
- [The efficacy of enterosorption and a combination of antioxidants in schizophrenics]
PubMed ID: 9784725
Antioxidant+enterosorbent complex containing quercetin improved lipid peroxidation indices in schizophrenia patients â indicates antioxidant effects within a multiâagent treatment.
- Bilberry juice modulates plasma concentration of NF-kappaB related inflammatory markers in subjects at increased risk of CVD
PubMed ID: 20119859
Bilberry juice increased plasma quercetin and changed several inflammation/oxidative markers (mixed but relevant to antioxidant effects).
Blood circulation (8)
- Targeting protein disulfide isomerase with the flavonoid isoquercetin to improve hypercoagulability in advanced cancer
PubMed ID: 30652973
Isoquercetin markedly lowered coagulation biomarkers and thrombin generation in cancer patientsâstrong evidence for reduced hypercoagulability and improved blood flow dynamics.
- Effect of onion peel extract on endothelial function and endothelial progenitor cells in overweight and obese individuals
PubMed ID: 26233871
12âweek 100 mg/day OPE improved flowâmediated dilation and increased circulating EPCsâstrong evidence of improved endothelial function/circulation.
- Effects of a quercetin-rich onion skin extract on 24 h ambulatory blood pressure and endothelial function in overweight-to-obese patients with (pre-)hypertension: a randomised double-blinded placebo-controlled cross-over trial
PubMed ID: 26328470
Modest 24 h systolic BP reduction in hypertensive subgroup suggests some circulatory benefit in that subgroup.
- Supplementation of the Pure Flavonoids Epicatechin and Quercetin Affects Some Biomarkers of Endothelial Dysfunction and Inflammation in (Pre)Hypertensive Adults: A Randomized Double-Blind, Placebo-Controlled, Crossover Trial
PubMed ID: 25972527
Quercetin-3-glucoside (160 mg/d) reduced sE-selectin (endothelial activation) in (pre)hypertensives â strong human vascular marker improvement.
- Polyphenolic compounds from red grapes acutely improve endothelial function in patients with coronary heart disease
PubMed ID: 16319551
Acute improvement in flow-mediated dilatation after a red grape polyphenol drink (small quercetin content) â vascular function improvement.
- Efficacy of orally administered extract of red vine leaf AS 195 (folia vitis viniferae) in chronic venous insufficiency (stages I-II). A randomized, double-blind, placebo-controlled trial
PubMed ID: 10719612
Red vine leaf extract containing quercetin glycosides reduced leg volume and calf circumference in chronic venous insufficiency, indicating improved peripheral circulation.
- Quercetin reduces systolic blood pressure and plasma oxidised low-density lipoprotein concentrations in overweight subjects with a high-cardiovascular disease risk phenotype: a double-blinded, placebo-controlled cross-over study
PubMed ID: 19402938
150 mg/day quercetin reduced systolic BP and oxidized LDL (clinically relevant vascular improvements).
- Quercetin Reduces Vascular Senescence and Inflammation in Symptomatic Male but Not Female Coronary Artery Disease Patients
PubMed ID: 40375481
Improved endotheliumâdependent relaxation (ACh EC50) and reduced vascular senescence markers indicate enhanced vascular function/circulation (maleâdriven effect).
Healthy aging (6)
- Quercetin intervention reduced hepatic fat deposition in patients with nonalcoholic fatty liver disease: a randomized, double-blind, placebo-controlled crossover clinical trial
PubMed ID: 39032786
12âweek RCT reduced liver fat and modest weight/BMI in NAFLD â metabolic improvements relevant to healthy aging.
- Characterization of Human Senescent Cell Biomarkers for Clinical Trials
PubMed ID: 39823170
Biomarkerâstratified D+Q increased bone formation/reduced resorption in high p16 burden subjects â evidence for senolytic/ageârelated benefit (combo).
- Effects of intermittent senolytic therapy on bone metabolism in postmenopausal women: a phase 2 randomized controlled trial
PubMed ID: 38956196
Dasatinib+quercetin senolytic trial produced transient increases in bone formation marker and subgroup BMD gains â notable healthyâaging (senolytic) signal.
- Interleukin-6 as a potential indicator for prevention of high-risk adenoma recurrence by dietary flavonols in the polyp prevention trial
PubMed ID: 20484173
Higher flavonol intake (quercetin major contributor) linked to lower ILâ6 and markedly lower advanced adenoma recurrenceâconsistent with longâterm health benefits.
- Quercetin, but Not Epicatechin, Decreases Plasma Concentrations of Methylglyoxal in Adults in a Randomized, Double-Blind, Placebo-Controlled, Crossover Trial with Pure Flavonoids
PubMed ID: 30398646
160 mg/day quercetin reduced methylglyoxal (an AGE precursor) ~11% in (pre)hypertensive adultsâmechanistic support for healthy aging via lower dicarbonyl stress.
- Quercetin Reduces Vascular Senescence and Inflammation in Symptomatic Male but Not Female Coronary Artery Disease Patients
PubMed ID: 40375481
Perioperative quercetin reduced arterial senescence markers (CDKN1A/GLB1) and improved endothelial function in men (direct agingârelated biomarker effects).
Skin health (7)
- Biological effects of rutin on skin aging
PubMed ID: 27220601
Topical rutin (quercetin glycoside) cream increased collagen markers and improved skin elasticity/wrinkles in a doubleâblind RCT.
- Annurca Apple Oleolite as Functional Ingredient for the Formulation of Cosmetics with Skin-Antiaging Activity
PubMed ID: 38338954
Topical apple oleogel containing quercetinârelated compounds improved elasticity, hydration and wrinkles over 28 days (clinical cosmetic endpoints; multiâingredient).
- Clinical and phytochemical studies of Plantago major in pressure ulcer treatment: A randomized controlled trial
PubMed ID: 33548748
Topical Plantago major standardized for quercetin content significantly improved early pressureâulcer healing in a randomized tripleâblind trialâstrong topical woundâhealing signal (multiâcomponent product).
- Management of aphthous ulceration with topical quercetin: a randomized clinical trial
PubMed ID: 20953559
Topical quercetin cream significantly accelerated healing, reduced ulcer size, and relieved pain in minor aphthous ulcers.
- Efficacy and Safety of Topical Compound Heparin Sodium Allantoin Gel (Main Components: Onion Extract Quercetin) for the Treatment of Rosacea
PubMed ID: 40177799
Topical gel containing onion extract (major active quercetin) plus heparin/allantoin significantly improved rosacea erythema, IGA and barrier measures in RCT with doxycycline coâtherapy.
- Comparison of clinical and histological effects between lactobacillus-fermented Chamaecyparis obtusa and tea tree oil for the treatment of acne: an eight-week double-blind randomized controlled split-face study
PubMed ID: 25228478
Randomized splitâface trial: fermented extract with increased quercetin reduced inflammatory and noninflammatory acne lesions and sebum vs tea tree oil (strong clinical skin outcome).
- Nano-hydrogel embedded with quercetin and oleic acid as a new formulation in the treatment of diabetic foot ulcer: A pilot study
PubMed ID: 31876118
Nanoâhydrogel with quercetin and oleic acid shortened woundâhealing time in diabetic lowerâlimb wounds (clinically important skin healing outcome).
Exercise recovery (6)
- Effects of quercetin ingestion on neuromuscular system following single session of resistance exercise at differing intensities in older adults
PubMed ID: 41056568
Acute preâexercise quercetin altered MU recruitment and correlated with greater postâexercise declines in evoked force (modulation of recovery processes).
- Quercetin ingestion alters motor unit behavior and enhances improvement in muscle strength following resistance training in older adults: a randomized, double-blind, controlled trial
PubMed ID: 40063125
Randomized trial of quercetin + resistance training in older adults showed larger strength gains and MU adaptations (direct exercise/recovery benefit).
- Effects of a Singular Dose of Mangiferin-Quercetin Supplementation on Basketball Performance: A Double-Blind Crossover Study of High-Level Male Players
PubMed ID: 38201999
Acute mangiferin+quercetin improved circuit performance and lowered RPE in athletes (singleâdose performance/recovery relevance; combo product).
- Effects of enzymatically modified isoquercitrin in supplementary protein powder on athlete body composition: a randomized, placebo-controlled, double-blind trial
PubMed ID: 31500646
EMIQ (bioavailable quercetin) + protein over 4 months increased lower-limb muscle mass and improved antioxidant indices in athletesâsupports recovery/repair, though coâadministered with protein.
- Effect of mixed flavonoids, n-3 fatty acids, and vitamin C on oxidative stress and antioxidant capacity before and after intense cycling
PubMed ID: 21813916
Quercetin-containing supplement raised plasma quercetin and attenuated the immediate postexercise rise in an oxidative stress marker (F2âisoprostanes).
- Supplementation with a Mango Leaf Extract (ZynamiteÂź) in Combination with Quercetin Attenuates Muscle Damage and Pain and Accelerates Recovery after Strenuous Damaging Exercise
PubMed ID: 32110986
Mangiferin + lowâdose quercetin reduced muscle soreness and attenuated performance loss and myoglobin rise after strenuous exercise â direct recovery outcome.
Respiratory comfort (4)
- Yindan Jiedu granules exhibit anti-inflammatory effect in patients with novel Coronavirus disease (COVID-19) by suppressing the NF-ÎșB signaling pathway
PubMed ID: 34785108
Hospitalized COVIDâ19 patients receiving multiâherb formula containing quercetin had faster resolution of pulmonary exudates and shorter time to viral clearance â respiratory outcomes improved though quercetin was one of many constituents.
- Correction of hypoxic effects on target organs in pneumonia with phytotherapy
PubMed ID: 39681530
Phytotherapy containing quercetin (plus other flavonoids) associated with improved respiratory/lab markers and increased ATPase activity in pneumonia patients (multiâcomponent clinical finding).
- Effects of repeated oral intake of a quercetin-containing supplement on allergic reaction: a randomized, placebo-controlled, double-blind parallel-group study
PubMed ID: 35776034
Phytosome quercetin reduced nasal allergy symptoms (sneezing, discharge) in pollinosis â directly relevant to upper airway comfort.
- Quercetin reduces illness but not immune perturbations after intensive exercise
PubMed ID: 17805089
Marked reduction in URTI incidence after intense exercise indicates improved respiratory comfort/susceptibility in that context.
Joint comfort (4)
- Comparison of shock wave therapy and nutraceutical composed of Echinacea angustifolia, alpha lipoic acid, conjugated linoleic acid and quercetin (perinerv) in patients with carpal tunnel syndrome
PubMed ID: 25953494
Nutraceutical (includes quercetin) improved pain and function in carpal tunnel patients up to 6 months â relevant to symptom relief around joints/entrapment syndromes.
- Effect of a dietary supplement containing glucosamine hydrochloride, chondroitin sulfate and quercetin glycosides on symptomatic knee osteoarthritis: a randomized, double-blind, placebo-controlled study
PubMed ID: 21969261
RCT of glucosamine/chondroitin with quercetin glycosides improved knee OA symptoms (multiâingredient, quercetin contribution uncertain).
- Glucosamine-containing supplement improves locomotor functions in subjects with knee pain: a randomized, double-blind, placebo-controlled study
PubMed ID: 26604721
16âweek multiâingredient supplement including quercetin glycosides improved knee symptoms and walking speed vs placebo.
- The Effect of Quercetin on Inflammatory Factors and Clinical Symptoms in Women with Rheumatoid Arthritis: A Double-Blind, Randomized Controlled Trial
PubMed ID: 27710596
RA RCT (500 mg/day) produced significant reductions in stiffness, pain and disease activityâstrong support for joint symptom relief.
Blood sugar (3)
- Epicatechin and quercetin exhibit in vitro antioxidant effect, improve biochemical parameters related to metabolic syndrome, and decrease cellular genotoxicity in humans
PubMed ID: 33773697
3-month enriched bread with quercetin+epicatechin reduced fasting plasma glucoseâstrong clinical signal for blood sugar improvement (combination).
- Effects of Quercetin on Adiponectin-Mediated Insulin Sensitivity in Polycystic Ovary Syndrome: A Randomized Placebo-Controlled Double-Blind Clinical Trial
PubMed ID: 27824398
PCOS RCT (1 g/day) lowered HOMAâIR and improved adiponectinâevidence for improved insulin sensitivity and glucose regulation.
- Efficacy of a standardized herbal product from Pistacia atlantica subsp. Kurdica in type 2 diabetic patients with hyperlipidemia: A triple-blind randomized clinical trial
PubMed ID: 35691258
Herbal product including rutin/quercetin reduced 2âhr postprandial glucose in T2DM â relevant to blood sugar control (indirect attribution).
Allergy relief (2)
- A polycentric, randomized, parallel-group, study on LertalÂź, a multicomponent nutraceutical, as preventive treatment in children with allergic rhinoconjunctivitis: phase II
PubMed ID: 31319883
Prolonged use of a quercetin-containing nutraceutical after antihistamine therapy halved exacerbation risk and reduced rescue medication daysâmeaningful allergy protection (multiâcomponent product).
- Effects of repeated oral intake of a quercetin-containing supplement on allergic reaction: a randomized, placebo-controlled, double-blind parallel-group study
PubMed ID: 35776034
Randomized, doubleâblind RCT (200 mg/day quercetin phytosome) reduced nasal/ocular allergy symptoms and improved QoL vs placebo (direct evidence).
Digestive support (2)
- Intestinal anti-spasmodic effect of a phytodrug of Psidium guajava folia in the treatment of acute diarrheic disease
PubMed ID: 12413703
Guavaâleaf phytodrug standardized for quercetin shortened abdominal pain duration in adults with acute diarrhea (randomized doubleâblind trial; multiâconstituent but quercetinâstandardized).
- Increased Plasma Levels of Gut-Derived Phenolics Linked to Walking and Running Following Two Weeks of Flavonoid Supplementation
PubMed ID: 30423955
Mixed flavonoid supplement plus exercise decreased markers of gut permeability (L/M ratio) vs placebo in runners â direct gut barrier/comfort relevance (multiâingredient).
Liver support (2)
- Effect of Daily Ingestion of Quercetin-Rich Onion Powder for 12 Weeks on Visceral Fat: A Randomised, Double-Blind, Placebo-Controlled, Parallel-Group Study
PubMed ID: 31905615
Quercetinârich onion lowered ALT vs placebo and reduced visceral fat in a subgroup â direct liver enzyme improvement signal.
- Quercetin intervention reduced hepatic fat deposition in patients with nonalcoholic fatty liver disease: a randomized, double-blind, placebo-controlled crossover clinical trial
PubMed ID: 39032786
12âweek RCT of 500 mg/day quercetin significantly reduced intrahepatic lipid content by MRI in NAFLD patients (direct liver benefit).
Energy & Fatigue (2)
- Effects of a Singular Dose of Mangiferin-Quercetin Supplementation on Basketball Performance: A Double-Blind Crossover Study of High-Level Male Players
PubMed ID: 38201999
Singleâdose mangiferin+quercetin improved circuit performance and lowered RPE in athletes (acute perceived/physiologic energy/endurance benefit; combo product).
- Quercetin ingestion alters motor unit behavior and enhances improvement in muscle strength following resistance training in older adults: a randomized, double-blind, controlled trial
PubMed ID: 40063125
Quercetin + resistance training increased strength gains in older adults â may translate to improved functional energy/endurance.
Brain health (1)
- Effect of quercetin glycosides on cognitive functions and cerebral blood flow: a randomized, double-blind, and placebo-controlled study
PubMed ID: 36524489
Long RCT in older adults showed improved reaction time (cognitive/brain function measure).
Mental clarity (1)
- Effect of quercetin glycosides on cognitive functions and cerebral blood flow: a randomized, double-blind, and placebo-controlled study
PubMed ID: 36524489
40âweek RCT in older adults showed significant improvement in reaction time (cognitive processing).
Eye health (1)
- Effects of repeated oral intake of a quercetin-containing supplement on allergic reaction: a randomized, placebo-controlled, double-blind parallel-group study
PubMed ID: 35776034
Quercetin phytosome RCT reduced ocular allergy symptoms (eye itching) in pollinosis patients (direct ocular symptom benefit).
Similar by evidence
Supplements the same benefits carry qualifying findings for â a fact about the evidence graph, not a recommendation to swap.
Products with Quercetin
Search all3484 products whose verified label declares Quercetin â not every bottle that mentions it in a title.
Being studied right now
Recruiting clinical trials registered on ClinicalTrials.gov. A trial in progress has no result yet â this is what the field is asking, not what it found.