Tier 2 — strong

Inter- and intra-individual variations in normal urinary glycine betaine excretion

Michael Lever, Wendy Atkinson, Peter C B Sizeland, Stephen T Chambers, Peter M George
Clinical biochemistry 2007 40(7):447-453

Bibliography

PubMed
PMID 17335790
DOI
10.1016/j.clinbiochem.2006.10.029
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

DesignRepeated-measure biomarker study
ModelHuman participants
SampleHealthy volunteers with repeat plasma and urine samples
InterventionMeasured betaine status and related metabolites; no randomized TMG treatment
DurationShort-term sampling with follow-up extending 12 years
EndpointsBetaine excretion; Long-term repeatability

What the study showed, in plain terms

Published in 2007, this source examined human observational and biomarker research. Design: Repeated-measure biomarker study. Sample/model: Healthy volunteers with repeat plasma and urine samples. The exposure or intervention was Measured betaine status and related metabolites; no randomized TMG treatment. Follow-up or treatment period: Short-term sampling with follow-up extending 12 years.

Individuals had relatively consistent urinary betaine excretion, with greater variation between people than within a person.

Observational exposure analysis: residual confounding and reverse causation remain possible. Associations do not establish that betaine supplementation causes the same outcome.

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Key findings

  • Individuals had relatively consistent urinary betaine excretion, with greater variation between people than within a person.
  • The recorded outcome domains were Betaine excretion; Long-term repeatability.
  • The result applies to the tested exposure: Measured betaine status and related metabolites; no randomized TMG treatment; Short-term sampling with follow-up extending 12 years.

What this study can and cannot tell us

  • Observational exposure analysis: residual confounding and reverse causation remain possible. Associations do not establish that betaine supplementation causes the same outcome.
  • 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

Reviewed by the Biohack Blueprint research team

Last verified

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