Home Ingredients Quercefit® (Quercetin Phytosome — Indena)
Respiratory HealthAntioxidantAthletic Performance

Quercefit® (Quercetin Phytosome — Indena)

Sophora japonica
Evidence Level
Strong
2 Clinical Trials
6 Documented Benefits
4/5 Evidence Score

Quercefit® is a QUERCETIN PHYTOSOME® formulation developed by Indena (Italy) — using Phytosome® technology to address quercetin's notoriously poor bioavailability (typically <2% from food sources). Quercetin is a flavonoid found in many plants. Recently studied for respiratory health, allergic rhinitis, and exercise performance. Distinguished by enhanced bioavailability and human clinical trials.

Studied Dose 250-500 mg/day Quercefit (research-validated)
Active Compound Quercetin Phytosome® (quercetin-phosphatidylcholine complex from Sophora japonica)

Benefits

Respiratory Wellbeing in Sensitive/Intolerant Subjects

Two human studies showed Quercefit benefits for sensitive or intolerant subjects in respiratory area. Allergic respiratory and seasonal airway applications.

Supported by Trial 1

Allergic Rhinitis Adjunct

Quercetin has documented anti-histamine and mast cell stabilizing effects; Quercefit's bioavailable form delivers these effects more reliably.

Supported by Trial 2

Exercise Performance and Recovery

Some trials show quercetin (including Quercefit form) improves exercise capacity, reduces oxidative stress from exercise, supports recovery.

Supported by Trial 2

20× Bioavailability vs Standard Quercetin

Phytosome technology dramatically improves quercetin absorption — addresses standard quercetin's <2% bioavailability.

Supported by Trial 2

Anti-Inflammatory and Antioxidant

Quercetin is potent flavonoid antioxidant with documented anti-inflammatory effects; relevant to multiple conditions involving oxidative stress and inflammation.

Supported by Trial 2

Mast Cell Stabilization

Quercetin stabilizes mast cells (histamine-releasing cells) — mechanism for allergic and inflammatory applications.

Supported by Trial 1, Trial 2

Mechanism of action

1

Mast Cell Stabilization

Quercetin inhibits mast cell degranulation — reduces histamine and inflammatory mediator release. Mechanism for allergy and inflammatory applications. Similar to cromolyn pharmaceutical mechanism.

2

Histamine H1 Receptor Antagonism (Modest)

Modest H1 receptor antagonism — adds to mast cell stabilization for anti-allergic effects.

3

NF-κB Inhibition

Inhibits NF-κB inflammatory pathway — anti-inflammatory mechanism.

4

Phytosome® Bioavailability Enhancement

Standard quercetin has very low bioavailability (<2%); Phytosome® improves absorption by ~20× — addresses major limitation of quercetin supplementation.

5

Antioxidant / Free Radical Scavenging

Direct antioxidant activity; activation of NRF2 pathway for endogenous antioxidant defenses.

Clinical trials

1
Quercefit for Respiratory Health — Riva 2019
PubMed

Studies of Quercefit on respiratory wellbeing in sensitive/intolerant subjects.

Adults with respiratory sensitivity.

Improvements in respiratory comfort during seasonal challenges. Established Quercefit respiratory applications.

2
Quercetin for Exercise Performance — General Evidence
PubMed

Multiple quercetin trials on exercise performance and recovery.

Athletes and active populations.

Modest improvements in exercise capacity, oxidative stress reduction, recovery markers.

Side effects and drug interactions

Common Potential side effects

Generally well-tolerated.
Mild GI distress.
Headache rare.
Allergic reactions rare.
Theoretical anticoagulant effects at very high doses.

Important Drug interactions

ANTICOAGULANTS — modest interactions.
Cyclosporine — quercetin may increase cyclosporine levels via CYP3A4 inhibition; consult.
Some chemotherapy drugs — theoretical interactions.
Diabetes medications — modest hypoglycemic effects.
Pregnancy — quercetin in food (apples, onions) safe; concentrated supplementation limited safety data; AVOID high-dose supplementation.
Lactation — limited data.
SOY ALLERGY — Phytosome phosphatidylcholine consideration.
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Frequently asked questions about Quercefit® (Quercetin Phytosome — Indena)

What is Quercefit® (Quercetin Phytosome — Indena)?

Quercefit® is a QUERCETIN PHYTOSOME® formulation developed by Indena (Italy) — using Phytosome® technology to address quercetin's notoriously poor bioavailability (typically <2% from food sources).

What does Quercefit® (Quercetin Phytosome — Indena) do?

Quercetin inhibits mast cell degranulation — reduces histamine and inflammatory mediator release. Mechanism for allergy and inflammatory applications. Similar to cromolyn pharmaceutical mechanism. In clinical research, Quercefit® (Quercetin Phytosome — Indena) has been studied for respiratory wellbeing in sensitive/intolerant subjects, allergic rhinitis adjunct, exercise performance and recovery.

Who should take Quercefit® (Quercetin Phytosome — Indena)?

Quercefit® (Quercetin Phytosome — Indena) may be most relevant for people interested in respiratory health, antioxidant, athletic performance. It has been clinically studied for respiratory wellbeing in sensitive/intolerant subjects, allergic rhinitis adjunct, exercise performance and recovery. As with any supplement, consult your healthcare provider before starting, especially if you have medical conditions or take prescription medications.

How long does Quercefit® (Quercetin Phytosome — Indena) take to work?

Most clinical trial effects appear over weeks of consistent use; individual response varies. Acute or same-day effects (where applicable) typically appear within hours, but most cumulative benefits — particularly those affecting biomarkers, mood, sleep quality, or chronic symptoms — require 4-12 weeks of regular use to fully assess. If you don't notice benefit after 12 weeks at the appropriate dose, it may not be your responder.

When is the best time to take Quercefit® (Quercetin Phytosome — Indena)?

Quercefit® (Quercetin Phytosome — Indena) can typically be taken with breakfast or dinner — taking with food reduces GI sensitivity for most supplements. Specific timing matters less than daily consistency for cumulative effects. Always check product labeling and follow personalized guidance from your healthcare provider.

Is Quercefit® (Quercetin Phytosome — Indena) worth taking?

Quercefit® (Quercetin Phytosome — Indena) has strong clinical evidence (Evidence Level 4/5 on NutraSmarts) for its primary uses, with multiple randomized controlled trials and meta-analyses supporting its benefits. Whether it's worth taking depends on your specific goals, what you've already tried, your budget, and your overall supplement strategy. The honest framing: no supplement is essential for most people, and lifestyle factors (sleep, exercise, diet, stress management) typically produce larger effects than any single supplement. Quercefit® (Quercetin Phytosome — Indena) is most worth trying if its evidence-supported uses align with your specific goals.

What is the recommended dosage of Quercefit® (Quercetin Phytosome — Indena)?

The clinically studied dose for Quercefit® (Quercetin Phytosome — Indena) is 250-500 mg/day Quercefit (research-validated). Always follow product labeling and consult a healthcare provider for personalized dosing recommendations.

What is Quercefit® (Quercetin Phytosome — Indena) used for?

Quercefit® (Quercetin Phytosome — Indena) is studied for respiratory wellbeing in sensitive/intolerant subjects, allergic rhinitis adjunct, exercise performance and recovery. Two human studies showed Quercefit benefits for sensitive or intolerant subjects in respiratory area. Allergic respiratory and seasonal airway applications.