Tier 4 — mechanistic

Glutathione synthesis is diminished in patients with uncontrolled diabetes and restored by dietary supplementation with cysteine and glycine

Sekhar RV, McKay SV, Patel SG, Guthikonda AP, Reddy VT, Balasubramanyam A, Jahoor F
Diabetes care 2011 34(1):162-167

Bibliography

PubMed
PMID 20929994
PubMed Central
PMC3005481
DOI
10.2337/dc10-1006
Funding
Indexed support: NCRR NIH HHS; NIDDK NIH HHS. See the publication for grant and funder details.
Competing interests
No dedicated competing-interest declaration was identified in the retrieved full text; absence of a statement is not evidence of no conflicts.

Study snapshot

DesignExploratory human intervention
ModelAdult humans
Sample12 adults with uncontrolled type 2 diabetes and 12 nondiabetic controls
InterventionGlycine 1.33 mmol/kg/day plus cysteine 0.81 mmol/kg/day as NAC
Duration14 days
EndpointsGlutathione synthesis; Glutathione concentration; Reactive oxygen metabolites; Lipid peroxidation

What the study showed, in plain terms

Combined glycine and cysteine precursor supplementation restored glutathione-related measures in a small diabetes study. Oxidative markers improved despite persistent hyperglycemia.

Key findings

  • The diabetes group had lower baseline glutathione synthesis than controls.
  • After supplementation, glutathione increased and oxidative-stress measures decreased.

What this study can and cannot tell us

No randomized diabetic placebo group and short follow-up.

It does not establish glycemic control, prevention of complications or glycine-only efficacy.

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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