Tier 2 — strong

Effects of the flavonoids quercetin and apigenin on hemostasis in healthy volunteers: results from an in vitro and a dietary supplement study

K Janssen, R P Mensink, F J Cox, J L Harryvan, R Hovenier, P C Hollman, M B Katan
The American journal of clinical nutrition 1998 67(2):255-62

Bibliography

PubMed
PMID 9459373
DOI
10.1093/ajcn/67.2.255
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

DesignRandomized dietary crossover study with supporting platelet experiments
ModelHuman intervention research
Sample18 healthy volunteers
InterventionOnions 220 g/day providing quercetin 114 mg/day; dried parsley providing apigenin 84 mg/day; or placebo
DurationEach food was consumed for 7 days within 2-week treatment periods
EndpointsExposure and pharmacokinetics; Platelet or coagulation measurements

What the study showed, in plain terms

Published in 1998, this source examined safety, interactions and special populations. Design: Randomized dietary crossover study with supporting platelet experiments. Sample/model: 18 healthy volunteers. The exposure or intervention was Onions 220 g/day providing quercetin 114 mg/day; dried parsley providing apigenin 84 mg/day; or placebo. Follow-up or treatment period: Each food was consumed for 7 days within 2-week treatment periods.

Neither food intervention changed measured hemostatic outcomes, although high concentrations inhibited platelets in vitro.

Dietary exposures were far below the concentrations needed for the strongest laboratory effect. Both the quercetin and apigenin arms belong in this shared paper record.

Continue with Quercetin Data Center

For topic-level interpretation, read Quercetin Side Effects and Safety: A Practical Guide. This is a related guide; the citation panel separately identifies articles that directly cite this paper.

Key findings

  • Neither food intervention changed measured hemostatic outcomes, although high concentrations inhibited platelets in vitro.
  • The recorded outcome domains were Exposure and pharmacokinetics; Platelet or coagulation measurements.
  • The result applies to the tested exposure: Onions 220 g/day providing quercetin 114 mg/day; dried parsley providing apigenin 84 mg/day; or placebo; Each food was consumed for 7 days within 2-week treatment periods.

What this study can and cannot tell us

  • Dietary exposures were far below the concentrations needed for the strongest laboratory effect. Both the quercetin and apigenin arms belong in this shared paper record.
  • 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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Citation network

Articles citing this research paper

2 articles

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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