Tier 2 — strong

The metabolic response to ingested glycine

Gannon MC, Nuttall JA, Nuttall FQ
The American journal of clinical nutrition 2002 76(6):1302-1307

Bibliography

PubMed
PMID 12450897
DOI
10.1093/ajcn/76.6.1302
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

DesignRandomized controlled human intervention
ModelAdult humans
Sample9 healthy adults
InterventionGlycine 1 mmol/kg lean body mass, 25 g glucose, their combination or water in random order
Duration2-hour acute tests
EndpointsGlucose response; Insulin and glucagon; Plasma glycine

What the study showed, in plain terms

In a small acute feeding experiment, adding glycine to glucose reduced the glucose excursion. This does not establish sustained diabetes control or improved long-term insulin sensitivity.

Key findings

  • The glucose area response was more than halved when glycine accompanied glucose.
  • Glycine increased glucagon; the integrated insulin response to glucose was not significantly increased by the combination.

What this study can and cannot tell us

Nine participants and a single-meal design limit translation to chronic metabolic disease.

The mechanism was inferred rather than directly demonstrated.

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Glycine treatment decreases proinflammatory cytokines and increases interferon-gamma in patients with type 2 diabetes
Cruz M et al. · Journal of endocrinological investigation · 2008
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Oral supplementation with glycine reduces oxidative stress in patients with metabolic syndrome, improving their systolic blood pressure
Díaz-Flores M et al. · Canadian journal of physiology and pharmacology · 2013
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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