Polyphenol1 form

Quercetin

Evidence Level

Moderate Evidence

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Quick Answer

What is Quercetin used for?

Quercetin is commonly used to support antioxidant. Our summary here is backed by 3 cited studies.

3cited studies

All Forms of Quercetin

Form	Tier	Form Score	Dose Range	Unit
Sophora japonica	Mapped	75/100Strong	—	—

Absorption by Form

Strong

Sophora japonica

75/100

What is Quercetin?

Quercetin is a Polyphenol supplement available in 1 form.

Not all forms of Quercetin are equal. The form you choose determines how much Quercetin actually reaches your tissues, and the difference between the best and worst forms can be substantial. FormulaForge ranks every form by how well it absorbs and how strongly the published research supports it, giving you an evidence-based guide for choosing wisely.

Forms of Quercetin Compared

Quercetin (Sophora japonica) (Mapped Form) has a bioavailability rating of lower absorption.

How to Choose the Right Form

Multiple forms of Quercetin are available. Start by comparing form ratings — Preferred Forms reflect the strongest bioavailability evidence, and higher-absorption forms deliver more active compound per dose unit.

The appropriate form depends on your individual goals and your healthcare provider’s recommendations. Consult a qualified professional before selecting a supplement form.

Dosing & Safety

Individual dose requirements vary based on health goals, body weight, and existing nutrient intake. Your healthcare provider can help you determine an appropriate amount of Quercetin for you.

Side Effects: Consult your healthcare provider regarding tolerability, particularly at higher doses.

These statements are based on structure/function research and have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease. Always consult a qualified healthcare provider before starting or changing a supplement regimen.

The Science

The following studies and findings inform FormulaForge classifications for Quercetin:

Quercetin aglycone vs rutin PK: aglycone reached Cmax faster with low inter-individual variation (double-blind crossover, n=16). PMID: 11151743

Onion-skin extract quercetin was 4.8x more bioavailable than pure quercetin dihydrate; aglycone is the reference comparator (crossover, n=12). PMID: 26482244

EMIQ (enzymatically modified isoquercitrin) raised circulating quercetin metabolites and improved endothelial function vs placebo; quercetin aglycone is the bioavailability baseline (crossover, n=25). PMID: 31870463

Dosing Guidance

Individual dose requirements for Quercetin vary based on health goals, body weight, and existing dietary intake. A qualified healthcare provider can help you determine an appropriate amount for you.

Frequently Asked Questions

What is Quercetin and what does it do?

Quercetin is a supplement commonly used to support Polyphenol. As with all supplements, talk to a qualified healthcare provider about whether it fits your specific goals.

How much Quercetin should I take?

Dosing for Quercetin varies based on the specific form, your health goals, and individual factors. Consult a qualified healthcare provider for personalized guidance.

What does Quercetin support?

Quercetin is commonly used to support Polyphenol. Research suggests it plays a role in several physiological pathways. As with all supplements, these statements have not been evaluated by the Food and Drug Administration and Quercetin is not intended to diagnose, treat, cure, or prevent any disease.

Is Quercetin safe?

Quercetin is generally well-tolerated when taken at research-supported doses. As with any supplement, individual responses vary. Consult a qualified healthcare provider before use, especially if you are pregnant, nursing, have a medical condition, or take medications. These statements have not been evaluated by the Food and Drug Administration.

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References

Quercetin aglycone vs rutin PK: aglycone reached Cmax faster with low inter-individual variation (double-blind crossover, n=16). PubMed DOI
Onion-skin extract quercetin was 4.8x more bioavailable than pure quercetin dihydrate; aglycone is the reference comparator (crossover, n=12). PubMed DOI
EMIQ (enzymatically modified isoquercitrin) raised circulating quercetin metabolites and improved endothelial function vs placebo; quercetin aglycone is the bioavailability baseline (crossover, n=25). PubMed DOI

FormulaForge formulates and sells supplements containing the ingredients discussed on this page. Our formulary recommendations are based on peer-reviewed bioavailability research. All cited studies are independently verifiable.