Tier 2 — strong

Quercetin reduces markers of oxidative stress and inflammation in sarcoidosis

Agnes W Boots, Marjolein Drent, Vincent C J de Boer, Aalt Bast, Guido R M M Haenen
Clinical nutrition (Edinburgh, Scotland) 2011 30(4):506

Bibliography

PubMed
PMID 21324570
DOI
10.1016/j.clnu.2011.01.010
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 acute sarcoidosis study
ModelHuman intervention research
Sample18 patients; 12 quercetin and 6 placebo
InterventionFour 500-mg quercetin doses within 24 hours
Duration24 hours
EndpointsInflammatory measures; Oxidative-stress measures

What the study showed, in plain terms

Published in 2011, this source examined immunity and respiratory health. Design: Double-blind placebo-controlled acute sarcoidosis study. Sample/model: 18 patients; 12 quercetin and 6 placebo. The exposure or intervention was Four 500-mg quercetin doses within 24 hours. Follow-up or treatment period: 24 hours.

Selected blood oxidative-stress and inflammatory markers decreased after quercetin.

Very small, brief biomarker study with unequal groups. Lung function, sustained symptoms, and long-term disease control were not established.

Continue with Quercetin Data Center

For topic-level interpretation, read Quercetin for Immune Health, Colds and COVID-19. This is a related guide; the citation panel separately identifies articles that directly cite this paper.

Key findings

  • Selected blood oxidative-stress and inflammatory markers decreased after quercetin.
  • The recorded outcome domains were Inflammatory measures; Oxidative-stress measures.
  • The result applies to the tested exposure: Four 500-mg quercetin doses within 24 hours; 24 hours.

What this study can and cannot tell us

  • Very small, brief biomarker study with unequal groups. Lung function, sustained symptoms, and long-term disease control were not established.
  • 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