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Enzymatically modified isoquercitrin in soy protein temporarily enhanced the plasma amino-acid concentrations, antioxidant index, and plasma hormone levels: a randomized, double-blind cross-over trial

Naomi Omi, Hayata Yamamoto, Taketo Yamaguchi, Motoki Tsukiashi, Takayuki Yamamoto, Ryo Tanaka, Koichi Watanabe, Hiroko Maruki-Uchida, Toshihiro Kawama
Amino acids 2023 55(6):769-776

Bibliography

PubMed
PMID 37154870
DOI
10.1007/s00726-023-03267-4
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 double-blind crossover nutrition study
ModelHuman intervention research
Sample9 healthy adults
InterventionSoy protein with or without enzymatically modified isoquercitrin 42 mg/day
Duration7 days per condition
EndpointsOxidative-stress measures; Exposure and pharmacokinetics

What the study showed, in plain terms

Published in 2023, this source examined exercise and recovery. Design: Randomized double-blind crossover nutrition study. Sample/model: 9 healthy adults. The exposure or intervention was Soy protein with or without enzymatically modified isoquercitrin 42 mg/day. Follow-up or treatment period: 7 days per condition.

Some post-meal amino-acid concentrations and exploratory antioxidant and hormone measures increased with the combination.

Very small short-term protein-feeding study. It does not demonstrate muscle growth or a durable testosterone benefit.

Continue with Quercetin Data Center

For topic-level interpretation, read Quercetin for Exercise: Performance, Recovery and Muscle. This is a related guide; the citation panel separately identifies articles that directly cite this paper.

Key findings

  • Some post-meal amino-acid concentrations and exploratory antioxidant and hormone measures increased with the combination.
  • The recorded outcome domains were Oxidative-stress measures; Exposure and pharmacokinetics.
  • The result applies to the tested exposure: Soy protein with or without enzymatically modified isoquercitrin 42 mg/day; 7 days per condition.

What this study can and cannot tell us

  • Very small short-term protein-feeding study. It does not demonstrate muscle growth or a durable testosterone benefit.
  • 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

Reviewed by the Biohack Blueprint research team

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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