Quercetin
Commonly used for
InflammationHealthy AgingHeart HealthAthletic Performance
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What is it? / Overview
Quercetin is a plant flavonoid with antioxidant and anti-inflammatory properties. The strongest evidence suggests modest benefits for exercise recovery and seasonal allergy symptoms although effects are generally small in healthy adults.
How is it used? / Administration
Form: Quercetin phytosome (preferred for bioavailability) or quercetin dihydrate
Typical dose studied: 500–1,000 mg/day
Timing: With fat-containing meals
Phytosome formulations provide substantially greater bioavailability than standard quercetin. Often combined with vitamin C or bromelain.
How well does it work? / Evidence
? Emerging / limited evidence
Who should avoid it?
Avoid with: Chronic kidney disease (Stage 3, 4, or 5) — NOT on dialysis; Dialysis (Hemodialysis or Peritoneal Dialysis)
Interacts with: Fluoroquinolone antibiotics; Cyclosporine; Anticoagulants — use caution
Already taking it? Reassess benefit after 8–12 weeks. Phytosome formulations provide substantially greater bioavailability.
Research & references
Li Y et al. (2016). Quercetin, inflammation and immunity. Nutrients. Somerville VS et al. (2016). Flavonoids and upper respiratory tract infections meta-analysis. Advances in Nutrition. Nieman DC et al. (2007). Quercetin and exercise-induced immune changes. Medicine & Science in Sports & Exercise.
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