The Claim

Reduced serum glutathione levels in humans consuming A1 beta-casein are correlated with altered cognitive performance as measured by the Subtle Cognitive Impairment Test (SCIT).

Source: Effect of A1 vs A2 beta‐casein containing diet on glutathione antioxidant status: Implications for inflammation and cognitive function via gut‐brain axis

What the research says

Supports is higher

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

Supports
40score
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

People who consume A1 beta-casein and have lower levels of glutathione in their blood show different scores on a test measuring subtle cognitive changes.

See the scientific wording

Reduced serum glutathione levels in humans consuming A1 beta-casein are correlated with changes in cognitive performance as measured by the Subtle Cognitive Impairment Test (SCIT), suggesting a potential link between oxidative stress and cognitive function.

Why this might work

When someone eats A1 beta-casein, their body breaks it down into a peptide called BCM-7. This peptide binds to opioid receptors in the gut and brain, which blocks the absorption of cysteine, a building block needed to make glutathione. Without enough glutathione, oxidative stress builds up in the body. This stress spreads from the gut to the brain through nerve and chemical signals, damaging brain cells and reducing cognitive performance.

Supported mechanismbased on 1 study

What the research says

1 study
  1. Study: Effect of A1 vs A2 beta‐casein containing diet on glutathione antioxidant status: Implications for inflammation and cognitive function via gut‐brain axis

    People who drank milk with A1 beta-casein had lower levels of a protective antioxidant called glutathione, and their cognitive test scores changed slightly. This suggests that this type of milk might affect brain function through oxidative stress.

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

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