“Quercetin?”Here!
Hasn’t appeared in a scanned product yet.
As a supplement
Talk to your doctor or pharmacist.
Roll Call does not check drug interactions or assess personal safety.
A yellow plant pigment belonging to the flavonoid family, found naturally in onions, apples, and many other fruits and vegetables. As a supplement it is extracted and concentrated into capsule or tablet form.
Why it’s used
Taken to support general antioxidant intake and sometimes for seasonal allergy symptoms or exercise recovery.
What the evidence says
Human trial evidence is mixed and generally modest. Some small trials suggest effects on blood pressure or exercise performance, but results are inconsistent and many studies are small or industry-funded. There is no NIH Office of Dietary Supplements fact sheet dedicated to quercetin, and no established therapeutic dose has been confirmed.
Dose studied
500–1000 mg — typical daily doses used in small human trials.
Context
Trials investigating quercetin have used daily doses in roughly the 500 to 1000 mg range over several weeks, with considerable variability in outcomes measured and populations studied.
Rumors
High-dose quercetin supplements can cause kidney damage.
Sources cited — check not cleared.
Studied in: male F344/N rats given high-dose dietary quercetin (NTP 2-year feed study).
Measured as an outcome.
- Abstract for TR-409 (Regulatory) · Funding not checked
Who’s saying this
- WebMD — a publisher: health information publisher; an Internet Brands company
How we know who this is
- “As a leader in digital health publishing for more than 25 years, WebMD strives to maintain the most comprehensive and reliable source of health and medical information on the internet.” (their page)
- “© 2005 - 2026 WebMD LLC, an Internet Brands company.” (their page)
Quercetin is a zinc ionophore that carries zinc into cells and raises cellular zinc levels.
We haven’t found evidence strong enough to support this or rule it out.
What was measured is not yet noted.
Who’s saying this
- Trace Minerals — a brand: sells mineral supplements
How we know who this is
- “At Trace Minerals, your satisfaction is our top priority.” (their page)
- “Every one of our products starts with the highest quality minerals and is backed by 50 years of research, sourcing experience, and ongoing commitment to perfect our process.” (their page)
- Trace Minerals — a brand: sells mineral supplements
Quercetin supplements reduce inflammation.
We haven’t found evidence strong enough to support this or rule it out.
What was measured is not yet noted.
Who’s saying this
- WebMD — a publisher: health information publisher; an Internet Brands company
How we know who this is
- “As a leader in digital health publishing for more than 25 years, WebMD strives to maintain the most comprehensive and reliable source of health and medical information on the internet.” (their page)
- “© 2005 - 2026 WebMD LLC, an Internet Brands company.” (their page)
- WebMD — a publisher: health information publisher; an Internet Brands company
Quercetin supplements support immune defense against viruses.
We haven’t found evidence strong enough to support this or rule it out.
What was measured is not yet noted.
Who’s saying this
- Trace Minerals — a brand: sells mineral supplements
How we know who this is
- “At Trace Minerals, your satisfaction is our top priority.” (their page)
- “Every one of our products starts with the highest quality minerals and is backed by 50 years of research, sourcing experience, and ongoing commitment to perfect our process.” (their page)
- Trace Minerals — a brand: sells mineral supplements
Quercetin is a natural antihistamine that relieves seasonal allergy symptoms by stabilizing mast cells and reducing histamine release.
Supports — suggestivehealth and safety evidence
Studied in: adults with pollen-sensitized allergic rhinitis.
Measured as an outcome.
- Quercetin and Its Lecithin-Based Formulation: Potential Applications for Allergic Diseases Based on a Narrative Review (Peer-reviewed) · Funded by Indena, Milan, Italy (industry) · No conflicts declared
Who’s saying this
- Ubie — a brand: AI symptom checker; sells targeted healthcare advertising to pharma advertisers
How we know who this is
- “Ubie is Japan's top healthcare startup.” (their page)
- “Ubie launches a self-serve platform that lets healthcare and pharma advertisers reach patients with targeted, clinically contextual placements inside Ubie's AI-driven patient experiences.” (their page)