Tier 4 — mechanistic

Glycine and N-acetylcysteine supplementation, with or without exercise, in brain health and functional aging: implications for sarcopenia and frailty in older adults

Wang X, Hou R, Chen Z, Wang X, Wang H
Frontiers in nutrition 2026 13:1775264

Bibliography

PubMed
PMID 42232577
PubMed Central
PMC13223053
DOI
10.3389/fnut.2026.1775264
Funding
Supported by the Xijing College Research Fund, grant XJ240210.
Competing interests
The authors declared no commercial or financial relationships that could represent a conflict of interest.

Study snapshot

DesignNarrative review
ModelHuman and preclinical literature
SampleReview of glycine, NAC, GlyNAC and exercise literature
InterventionGlycine/NAC interventions and possible combination with exercise
DurationNot applicable; 2026 review
EndpointsMuscle and cognitive function; Oxidative stress; Frailty and sarcopenia

What the study showed, in plain terms

This 2026 review considers GlyNAC and exercise as potential approaches to functional aging. It brings together mechanistic and clinical literature, including interventions with different ingredients.

Key findings

  • The authors describe promising but heterogeneous GlyNAC evidence.
  • Glycine derivatives and NAC-alone studies are also discussed.

What this study can and cannot tell us

Narrative review, not a new randomized GlyNAC-plus-exercise trial.

Evidence for derivatives or combinations cannot establish equivalent effects of plain glycine.

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A Randomized Controlled Clinical Trial in Healthy Older Adults to Determine Efficacy of Glycine and N-Acetylcysteine Supplementation on Glutathione Redox Status and Oxidative Damage
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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