Tier 4 — mechanistic

Dietary glycine improves urine storage symptoms in urology outpatients

Sugaya K, Oh-Oka H, Yamada T, Miyata M, Ashitomi K, Kadekawa K, Nishijima S
Journal of complementary & integrative medicine 2021 18(3):617-620

Bibliography

PubMed
PMID 33793143
DOI
10.1515/jcim-2020-0282
Funding
Funding was not specified in the indexed abstract; the full funding disclosure has not been verified.
Competing interests
The accessible abstract does not establish the authors' competing interests; absence of a statement is not evidence of no conflicts.

Study snapshot

DesignExploratory human intervention
ModelAdult humans
Sample20 urology outpatients: 16 men and 4 women
InterventionGlucose placebo 3 g twice daily first, then glycine 3 g twice daily
Duration4 weeks placebo followed by 4 weeks glycine
EndpointsOveractive bladder symptoms; Nocturnal urination; Sleep latency; Blood pressure and quality of life

What the study showed, in plain terms

This exploratory study reported better urinary-storage symptoms during glycine use. All participants received placebo first and glycine second, making sequence and expectation effects important alternative explanations.

Key findings

  • Nocturnal voiding and selected urgency, symptom and quality-of-life measures improved.
  • No adverse events were reported in this small sample.

What this study can and cannot tell us

Fixed-order, nonrandomized intervention with many outcomes.

It cannot establish efficacy for overactive bladder, insomnia or hypertension.

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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