Tier 2 — strong

Promising Effects of 3-Month Period of Quercetin Phytosome® Supplementation in the Prevention of Symptomatic COVID-19 Disease in Healthcare Workers: A Pilot Study

Mariangela Rondanelli, Simone Perna, Clara Gasparri, Giovanna Petrangolini, Pietro Allegrini, Alessandro Cavioni, Milena Anna Faliva, Francesca Mansueto, Zaira Patelli, Gabriella Peroni, Alice Tartara, Antonella Riva
Life (Basel, Switzerland) 2022 12(1):66

Bibliography

PubMed
PMID 35054459
PubMed Central
PMC8780248
DOI
10.3390/life12010066
Funding
Funding was not specified in the indexed record or the disclosure metadata available for this entry.
Competing interests
Reported disclosure: The authors declare no conflict of interest.

Study snapshot

DesignPlacebo-comparator healthcare-worker prevention pilot
ModelHuman intervention research
Sample120 participants; 60 per group
InterventionQuercetin Phytosome 250 mg twice daily, expressed as formulation weight
Duration3 months of supplementation
EndpointsSymptoms and quality of life

What the study showed, in plain terms

Published in 2022, this source examined immunity and respiratory health. Design: Placebo-comparator healthcare-worker prevention pilot. Sample/model: 120 participants; 60 per group. The exposure or intervention was Quercetin Phytosome 250 mg twice daily, expressed as formulation weight. Follow-up or treatment period: 3 months of supplementation.

Five symptomatic COVID-19 cases occurred: one in the supplement group and four in controls.

Extremely few events and incompletely described allocation limit confidence. Formulation weight is not necessarily quercetin content, and the study does not establish reliable infection prevention.

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

  • Five symptomatic COVID-19 cases occurred: one in the supplement group and four in controls.
  • The recorded outcome domains were Symptoms and quality of life.
  • The result applies to the tested exposure: Quercetin Phytosome 250 mg twice daily, expressed as formulation weight; 3 months of supplementation.

What this study can and cannot tell us

  • Extremely few events and incompletely described allocation limit confidence. Formulation weight is not necessarily quercetin content, and the study does not establish reliable infection prevention.
  • 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

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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