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Compare our Quercetin with other brands.
See the difference for yourself. Compare what’s inside, spot the added extras, and see what sets Crown Supplements apart.
| Brand & product | Added bulking ingredients | Added flow or anti-caking agents |
|---|---|---|
| Crown SupplementsQuercetin Extract | None added by Crown Supplements | None added by Crown Supplements |
| Holland & BarrettQuercetin Plus Vitamin C | YESCalcium carbonate, microcrystalline cellulose | YESMagnesium salts of fatty acids, fatty acids, silicon dioxide |
| SolgarQuercetin Complex with Ester-C Plus | YESMaltodextrin, microcrystalline cellulose | YESMagnesium stearate, stearic acid, silicon dioxide |
| NOW FoodsQuercetin with Bromelain | YESMicrocrystalline cellulose | YESMagnesium stearate, silicon dioxide |
| SwansonQuercetin 475mg | YESMicrocrystalline cellulose | YESMagnesium stearate, silica |
Quercetin with 98.05% measured raw-material purity.
173mg of Sophora japonica extract per capsule, with a raw-material COA result of 98.05% quercetin. That calculates to approximately 169.6mg quercetin per capsule. No fillers, binders or machine flow agents added by Crown Supplements.
Your formula at a glance
Look inside the formula.
Choose a Quercetin formula with the ingredient concentration and additional ingredients made clear. Crown Supplements states the raw-material assay and keeps the formula focused on the named extract.
98.05% quercetin.
The raw-material certificate quantifies the quercetin content.
Keep production extras out.
No maltodextrin, magnesium stearate or silicon dioxide added by Crown Supplements.
The details that make the difference.
Quantified content
The extract weight and calculated quercetin amount are stated separately.
Botanical source disclosed
The certificate identifies Sophora japonica fruit as the source.
Compare the ingredient list
Look beyond front-label milligrams to the bulking and flow ingredients.
A closer look at your formula.
Concentrated quercetin
98.05% raw-material assay.
Named source
Sophora japonica L.
Plant part identified
Fruit extract on the certificate.
Clear extract weight
173mg per capsule.
Our formulation
No fillers, binders or machine flow agents added by Crown Supplements.
Four pouch sizes
Choose 90, 180, 270 or 360 capsules.
The ingredient comes first.
No fillers, binders or machine flow agents added by Crown Supplements.
Choose the pouch that fits your routine.
The same formula in every pouch. Choose your capsule count:
Quercetin Extract Capsules — product details.
How to use and store.
Frequently asked questions.
Quercetin with 98.05% measured raw-material purity.
High-concentration Quercetin extract with its source and assay result disclosed.
No fillers, binders or machine flow agents added by Crown Supplements.
Select 90, 180, 270 or 360 capsules in the purchase panel above.
Bought these for my mum… very happy as she has problems swallowing… these are ideal as they are tasteless and can be added to food or drinks…
found these quercetin capsules while searching for something with proper potency 98 percent sophora japonica extract is legit great value for a clean immune support supplement with no fillers definitely sticking with this brand
Quercetin seems to help when my knees feel stiff after busy days. I like that it is a single ingredient supplement, no fillers
My hips feel less stiff when I keep up with quercetin. It took a little while, but I notice when I miss a few days
quercetin is one I keep for seasonal rough patches. it seems to help me feel clearer, and the capsule list is nice and short
quercetin wasn’t something I planned to buy, but it’s stayed in my routine. I feel a bit clearer during seasonal spells
Quercetin Sophora Japonica
A quick uk supplements order and the bottle was clear. quercetin capsules are more convenient for me than powder
Asked to review after 14 days but item still not received so can’t review. Very slow delivery though!
Quercetin capsules are easier than hunting for powders. i liked the simple label and quick postage