Tier 2 — strong

Dietary precursors of trimethylamine in man: a pilot study

A Q Zhang, S C Mitchell, R L Smith
Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association 1999 37(5):515-520

Bibliography

PubMed
PMID 10456680
DOI
10.1016/s0278-6915(99)00028-9
Funding
Funding was not specified in the indexed record or accessible funding metadata.
Competing interests
A competing-interest declaration was not available in the indexed record or accessible disclosure metadata.

Study snapshot

DesignHuman precursor-challenge pilot
ModelHuman participants
SampleHealthy volunteers in precursor and food challenges
InterventionSingle oral 15 mmol doses of selected trimethylamine precursors, including betaine
DurationAcute urinary metabolite assessment
EndpointsTrimethylamine; TMAO; Precursor metabolism

What the study showed, in plain terms

Published in 1999, this source examined food sources, absorption and nutrient metabolism. Design: Human precursor-challenge pilot. Sample/model: Healthy volunteers in precursor and food challenges. The exposure or intervention was Single oral 15 mmol doses of selected trimethylamine precursors, including betaine. Follow-up or treatment period: Acute urinary metabolite assessment.

Choline, carnitine and TMAO increased urinary trimethylamine-related products, while betaine did not produce a significant increase in this experiment.

Small acute study with urinary rather than long-term clinical outcomes; results do not rule out context-dependent TMAO responses.

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Key findings

  • Choline, carnitine and TMAO increased urinary trimethylamine-related products, while betaine did not produce a significant increase in this experiment.
  • The recorded outcome domains were Trimethylamine; TMAO; Precursor metabolism.
  • The result applies to the tested exposure: Single oral 15 mmol doses of selected trimethylamine precursors, including betaine; Acute urinary metabolite assessment.

What this study can and cannot tell us

  • Small acute study with urinary rather than long-term clinical outcomes; results do not rule out context-dependent TMAO responses.
  • 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: Indexed abstract and bibliographic data. 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