Tier 2 — strong

Supplementation with quercetin markedly increases plasma quercetin concentration without effect on selected risk factors for heart disease in healthy subjects

J A Conquer, G Maiani, E Azzini, A Raguzzini, B J Holub
The Journal of nutrition 1998 128(3):593-7

Bibliography

PubMed
PMID 9482769
DOI
10.1093/jn/128.3.593
Funding
Funding was not specified in the indexed record or the disclosure metadata available for this entry.
Competing interests
A competing-interest declaration was not available in the indexed record or the disclosure metadata used for this entry.

Study snapshot

DesignDouble-blind placebo-controlled supplementation study
ModelHuman intervention research
SampleHealthy adults; sample size not stated in the indexed abstract
InterventionQuercetin-containing capsules providing 1,000 mg/day or placebo
Duration28 days
EndpointsBlood pressure; Lipid measurements; Exposure and pharmacokinetics; Platelet or coagulation measurements

What the study showed, in plain terms

Published in 1998, this source examined cardiovascular and metabolic health. Design: Double-blind placebo-controlled supplementation study. Sample/model: Healthy adults; sample size not stated in the indexed abstract. The exposure or intervention was Quercetin-containing capsules providing 1,000 mg/day or placebo. Follow-up or treatment period: 28 days.

Plasma quercetin rose markedly, but lipids, blood pressure, platelet measures, and other selected cardiovascular-risk markers did not improve.

Short trial in generally healthy adults; exposure alone should not be interpreted as cardiovascular protection.

Continue with Quercetin Data Center

For topic-level interpretation, read Quercetin and Blood Pressure: How Large Is the Effect?. This is a related guide; the citation panel separately identifies articles that directly cite this paper.

Key findings

  • Plasma quercetin rose markedly, but lipids, blood pressure, platelet measures, and other selected cardiovascular-risk markers did not improve.
  • The recorded outcome domains were Blood pressure; Lipid measurements; Exposure and pharmacokinetics; Platelet or coagulation measurements.
  • The result applies to the tested exposure: Quercetin-containing capsules providing 1,000 mg/day or placebo; 28 days.

What this study can and cannot tell us

  • Short trial in generally healthy adults; exposure alone should not be interpreted as cardiovascular protection.
  • An individual controlled trial must be interpreted alongside its comparator, sample size, endpoint selection and independent replication. It does not validate a different commercial formulation or a general longevity claim.
  • Source basis: Source check: PubMed abstract and indexed metadata; full methods were not independently confirmed for this entry. Missing method details, funding information or participant denominators are not inferred.

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Editorial review

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Dr. Khaled Mahmoud, MBBChCritical Care Medicine, Longevity Science & Editorial Direction Dr. Amr Yasser, PhDCardiometabolic, Musculoskeletal, Gut & Bioavailability Dr. Abdulla Mostafa, PhDCellular Senescence, Neurological, Mitochondrial & Brain-Ageing Biology