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Supplements

quercetin phytosome increases plasma quercetin

In plain terms: Do the expensive 'phytosome' and EMIQ forms of quercetin actually absorb better?

Strong support Supplements

Part of: 🧪 quercetin

RefutedContestedStrong support
consensus score 0.62

Better absorption is real and it's quercetin's most solid finding, since plain quercetin absorbs badly. But no independent head-to-head trial of the actual products on sale exists, and much of the supporting research tested different formulations entirely.

📅 Last reviewed: 2026-07-26

Evidence ladder

How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."

Top evidence so far: All trials, pooled (Meta-analysis)

MechanismIn-vitroAnimalObservationalRCTMeta-analysis

How the studies fall

1 support 0 contradict 0 tested null 6 mixed · 7 sources, 1 independent group

What the evidence shows

Quercetin's poor absorption is real, and enhanced formulations do raise plasma levels — but the specific products people pay a premium for are less studied than the marketing implies. The evidence rests on a single meta-analysis of 31 human intervention studies reporting large fold-increases (around 20x for lecithin phytosome, 10x for cyclodextrin, higher for a galactomannan-lecithin combination).

The evidence (7)

SourceGradeStanceQualityFinding
Kannan S et al
2026 · Preprints.org
in-vitro mixed low Preprint, not peer-reviewed: renatured beta-1,3-1,6-glucan nanoparticles raised apparent aqueous solubility of quercetin to 1,620 +/- 15.3 uM vs 347 +/- 16.4 uM for a beta-cyclodextrin complex and 7.11 +/- 3.97 uM for free quercetin (~228-f TEMPERED: unreviewed preprint measuring SOLUBILITY in vitro, not plasma exposure.
Liu R et al
2026 · study_type: animal
animal mixed low Novel deep-eutectic-solvent-in-water (menthol:capric-acid 7:3) microemulsion vs free quercetin: oral AUC0-t was 5.54-fold higher in 'pharmacokinetic studies' whose species and n are not stated in the abstract (preclinical formulation-develo TEMPERED: deep-eutectic-solvent microemulsion — a different formulation chemistry from the marketed phytosome/EMIQ products this claim is about.
Ke L et al
2026 · study_type: animal
animal mixed low Food-grade excipient nanoemulsion co-ingested with spinach vs spinach alone, evaluated via INFOGEST in-vitro digestion plus an in-vivo rat study (n not stated): increased in-vitro bioaccessibility 1.73-fold and in-vivo bioavailability by 46 TEMPERED: food-grade excipient nanoemulsion with a spinach matrix, not a phytosome product; and only ~1.5x, far below the headline fold-increases.
Liu L et al
2025 · study_type: meta-analysis
meta-analysis supports moderate Systematic review/meta-analysis of 31 human intervention studies (blood/urine) found lecithin phytosome gave a 20.1-fold bioavailability increase and self-emulsifying fenugreek-galactomannan+lecithin encapsulation a 62-fold increase vs quer
Aslam S et al
2026 · study_type: animal
animal mixed low PK study of an intranasal mucoadhesive in-situ gel co-delivering PEG-conjugated quercetin (Q-PEG) with rivastigmine-loaded chitosan nanoparticles (RVS-Q-PEG-CNPsG) found brain bioavailability enhanced 5.6-fold and 12.6-fold vs. intranasal f TEMPERED: intranasal gel measuring BRAIN delivery, not oral plasma exposure of a marketed phytosome/EMIQ product.
Dohmen CGM et al
2026 · study_type: in-vitro
in-vitro mixed low In differentiated Caco-2 cells, an equimolar 1:1:1 quercetin:kaempferol:isoquercetin mixture (100 μM each) doubled quercetin absorption vs. quercetin alone at equal dose, attributed to kaempferol's inhibition of efflux transporters. NOT a p TEMPERED: Caco-2 monolayer with a 3-flavonoid mixture — not a phytosome/EMIQ product and not systemic exposure.
Ding Y et al
2026 · study_type: animal
animal mixed low In vivo PK (species/n not stated) comparing quercetin absorption-enhancers: punicic-acid ethyl ester (PAEE) alone raised oral bioavailability 4.57-fold vs free quercetin, and a PAEE nanoemulsion raised it 20.66-fold (pomegranate-seed-oil an TEMPERED: punicic-acid-ester nanoemulsion, not a phytosome product.

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