Tier 2 — strong

A quercetin containing supplement reduces niacin-induced flush in humans

D Kalogeromitros, M Makris, C Chliva, X Aggelides, D Kempuraj, T C Theoharides
International journal of immunopathology and pharmacology 2008 21(3):509

Bibliography

PubMed
PMID 18831918
DOI
10.1177/039463200802100304
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

DesignUncontrolled acute niacin-flush pilot with laboratory support
ModelHuman intervention research
Sample4 healthy men
InterventionNiacin 1 g alone or after a quercetin-containing multi-ingredient formulation
DurationAcute challenge comparisons
EndpointsSource-specific outcomes described in the key findings

What the study showed, in plain terms

Published in 2008, this source examined safety, interactions and special populations. Design: Uncontrolled acute niacin-flush pilot with laboratory support. Sample/model: 4 healthy men. The exposure or intervention was Niacin 1 g alone or after a quercetin-containing multi-ingredient formulation. Follow-up or treatment period: Acute challenge comparisons.

Self-reported flushing intensity and duration were lower with the supplement formulation.

Very small unblinded pilot without a robust placebo control. The effect cannot be assigned to quercetin alone or generalized to medication safety.

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

  • Self-reported flushing intensity and duration were lower with the supplement formulation.
  • The recorded outcome domains were Source-specific outcomes described in the key findings.
  • The result applies to the tested exposure: Niacin 1 g alone or after a quercetin-containing multi-ingredient formulation; Acute challenge comparisons.

What this study can and cannot tell us

  • Very small unblinded pilot without a robust placebo control. The effect cannot be assigned to quercetin alone or generalized to medication safety.
  • Without a sufficiently blinded concurrent control, time effects, expectations, co-interventions and regression toward the mean can explain part of an apparent improvement.
  • 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