Tier 2 — strong

Effect of Daily Ingestion of Quercetin-Rich Onion Powder for 12 Weeks on Visceral Fat: A Randomised, Double-Blind, Placebo-Controlled, Parallel-Group Study

Mie Nishimura, Takato Muro, Masuko Kobori, Jun Nishihira
Nutrients 2019 12(1):91

Bibliography

PubMed
PMID 31905615
PubMed Central
PMC7019606
DOI
10.3390/nu12010091
Funding
Indexed grant support: none — Bio-oriented Technology Research Advancement Institution, NARO. The indexed list may not contain the complete funding declaration.
Competing interests
Reported disclosure: The authors declare no conflict of interest.

Study snapshot

DesignRandomized double-blind placebo-controlled food trial
ModelHuman intervention research
Sample70 adults with BMI 23 to below 30
InterventionQuercetin-rich onion powder 9 g/day versus placebo onion
Duration12 weeks
EndpointsLipid measurements; Liver measurements

What the study showed, in plain terms

Published in 2019, this source examined cardiovascular and metabolic health. Design: Randomized double-blind placebo-controlled food trial. Sample/model: 70 adults with BMI 23 to below 30. The exposure or intervention was Quercetin-rich onion powder 9 g/day versus placebo onion. Follow-up or treatment period: 12 weeks.

The primary visceral-fat comparison was null. A lower-HDL subgroup and an ALT measure showed favorable signals.

The subgroup finding does not establish an overall fat-loss effect. Whole-onion results are not equivalent to capsule supplementation.

Continue with Quercetin Data Center

For topic-level interpretation, read Quercetin for Weight Loss, Blood Sugar and Fatty Liver: Human Evidence. This is a related guide; the citation panel separately identifies articles that directly cite this paper.

Key findings

  • The primary visceral-fat comparison was null.
  • A lower-HDL subgroup and an ALT measure showed favorable signals.
  • The recorded outcome domains were Lipid measurements; Liver measurements.
  • The result applies to the tested exposure: Quercetin-rich onion powder 9 g/day versus placebo onion; 12 weeks.

What this study can and cannot tell us

  • The subgroup finding does not establish an overall fat-loss effect. Whole-onion results are not equivalent to capsule supplementation.
  • 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: accessible full text and indexed metadata. 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