The Claim

In aged female mice, a 12-week GlyNAC-supplemented diet is associated with reduced exercise performance, including lower time to exhaustion and reduced maximum work capacity, despite no improvement in cardiac mitochondrial biomarkers.

Source: Sex Differences in Response to Diet Enriched With Glutathione Precursors in the Aging Heart

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
21score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Correlation
1 study reviewed
In plain English

In older female mice, a diet supplemented with GlyNAC for 12 weeks resulted in decreased exercise endurance, measured by shorter time to exhaustion and lower maximum work output, without improving markers of heart muscle mitochondria.

See the scientific wording

In aged female mice, a 12-week GlyNAC-supplemented diet is associated with reduced exercise performance, including lower time to exhaustion and reduced maximum work capacity, despite no improvement in cardiac mitochondrial biomarkers, suggesting a potential adverse effect on physical endurance.

Why this might work

In older female mice, taking GlyNAC raises glutathione levels too high, which disrupts the normal redox balance in heart cells. This excess glutathione shuts down key enzymes needed to burn fat for energy, causing the heart to struggle to produce power during exercise. As a result, the mice tire faster and cannot perform as well.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: Sex Differences in Response to Diet Enriched With Glutathione Precursors in the Aging Heart

    In older female mice, adding GlyNAC to their diet made them get tired faster during exercise, even though their heart's energy systems didn't get better — which means the supplement might have hurt their stamina.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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