Ingredient Guide

Quercetin: A Plant Flavonoid Valued as an Antioxidant

Quercetin is a flavonoid — a plant pigment found in onions, apples, and berries — valued mainly as a dietary antioxidant. It's one of the most-studied flavonoids, taken as a plant compound that helps the body deal with everyday oxidative stress.

  • Evidence-based
  • Structure/function only
  • No proprietary blends

What it is

Quercetin is a flavonoid present in many fruits, vegetables, and teas. In supplements it's concentrated well above food levels, and it's often paired with vitamin C or bromelain, which are sometimes used to support its absorption.

How it works

As an antioxidant, quercetin can scavenge free radicals and help reduce oxidative stress at the cellular level — the structure-function basis for its inclusion in wellness formulas. Its absorption from supplements is limited, which is why formulation and dose are part of the conversation.

Why the form & source matter

Plain quercetin isn't absorbed especially well, so products often combine it with absorption helpers or use modified forms. As with most antioxidants, a consistent daily intake fits the ingredient better than occasional large doses.

How Monthlees uses it

Right now there isn't a clean, standalone Monthlees product to feature for quercetin. Treat this page as background on the ingredient; product cards can be added if and when a suitable quercetin product is in the catalog.

Frequently asked questions

What is quercetin?

A flavonoid (plant pigment) found in foods like onions, apples, and berries, used as a dietary antioxidant.

What does it do?

It acts as an antioxidant, helping the body manage oxidative stress at the cellular level.

Why is it paired with vitamin C?

Vitamin C and ingredients like bromelain are sometimes used alongside it; plain quercetin is absorbed poorly.

Where is it found in food?

Onions, apples, berries, and tea are common sources.

Research & references

  1. Recent Advances in Potential Health Benefits of Quercetin — Pharmaceuticals (Basel) (2023) (source)
    Quercetin's antioxidant properties scavenge free radicals and reduce oxidative stress at the cellular level; cited for antioxidant/cellular framing only.
  2. The Potential Benefits of Quercetin for Brain Health: A Review of Anti-Inflammatory and Neuroprotective Mechanisms — International Journal of Molecular Sciences (2023) (source)
    Quercetin exhibits antioxidant activity at the cellular level; cited for antioxidant/cellular framing only.

References are provided for general educational context. They do not imply that this product treats, cures, or prevents any disease.

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

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