Quercetin
Scored by the Formulate Research Team · Last reviewed July 2026
Score Breakdown
Three factors carry this score; three more are checked separately and can only take points away. Hover or tap to see what drove each one.
Ingredients per Serving
| Ingredient | Amount |
|---|---|
| Quercetin Bioflavonoids extract | 235 mg |
| Citrus Bioflavonoids extract | 235 mg |
| Bromelain4 systematic reviews · 27 randomised trials | 45 mg |
| Rutin extract | 45 mg |
Certifications & Testing
Other Ingredients
Gelatin Capsule, Rice powder, Magnesium Stearate, Silica
Recommended Use
Suggested Usage: 1 capsule 1-3 times per day or as directed by a health professional.
Warnings
Cautions: As with any supplement, consult your health professional before use if you are pregnant, breastfeeding, or trying to conceive, or if you are taking medication, have a medical condition, or anticipate a surgery. Keep out of the reach of children. Sealed for your protection. Do not use if seal is broken.
Frequently Asked Questions
What is Natural Factors Quercetin's Formulate score?
Natural Factors Quercetin scores 72 out of 100 (grade B) on Formulate's ingredient-level rubric: clinical evidence, dose accuracy and bioavailability carry the score, while manufacturing, transparency and safety are checked separately and can only deduct.
Is Natural Factors Quercetin worth it?
Natural Factors Quercetin scores 72/100 (grade B). That's an above-average result — most of its doses and ingredient forms are well-chosen, with only minor gaps in dosing, transparency, or testing. Formulate grades every product with the same automated rubric, so the score reflects the formula — not marketing or sponsorships.
What's in Natural Factors Quercetin?
Each serving contains Quercetin Bioflavonoids extract (235 mg), Citrus Bioflavonoids extract (235 mg), Bromelain (45 mg), Rutin extract (45 mg). Serving size: 1 Capsule(s). 60 servings per container.
How do I take quercetin?
Suggested Usage: 1 capsule 1-3 times per day or as directed by a health professional.
Who makes Quercetin?
Quercetin is made by Natural Factors. See Formulate's full grade and product lineup for Natural Factors on its brand page.
Is Natural Factors Quercetin third-party tested?
Natural Factors lists the following certifications and testing for this product: Gluten-Free, Dairy-Free, Sugar-Free.
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Disclosure. Formulate may earn a commission from purchases made through links on this page. Commissions never influence scores — every product is graded by the same automated rubric. This page is for educational purposes only and does not replace advice from a qualified healthcare provider.