The Study
Effect of A1 vs A2 beta‐casein containing diet on glutathione antioxidant status: Implications for inflammation and cognitive function via gut‐brain axis
This study found that people who drank milk with A1 protein had lower levels of a protective chemical in their blood and sometimes felt a little worse mentally. But it didn't prove the milk caused those changes — maybe those people ate other unhealthy things too.
Analysis score
Maximum 45 for a randomized controlled trial.
Where the score came from
Some milk has a protein (A1 beta-casein) that turns into a morphine-like substance (BCM-7) in your gut, which may block a key nutrient needed to make an antioxidant called glutathione.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 540 / 100
Quality score
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes — lower glutathione may mean more oxidative stress, which is linked to brain fog and inflammation, so this could matter for sensitive people.
- 2People drinking A1 milk had lower glutathione (p<0.05, n=45).
- 3Mice on A1 milk had less glutathione in brain, liver, and gut, and more inflammation (p<0.05, n=12).
- 4Their thinking tests also changed.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
The FASEB Journal
Year
2017
Authors
Malav S Trivedi, Yiting Zhang, R. Deth
Related Content
Claims (6)
Beta-casomorphin-7, a peptide from milk protein, binds to mu-opioid receptors in the brain and increases food intake by activating neural reward circuits.
Beta-casomorphin-7, a peptide formed when digesting A1 beta-casein milk protein, decreases cysteine absorption in human gut and nerve cells, which reduces the production of glutathione.
A2 milk, which lacks A1 beta-casein, is linked to increased glutathione levels and reduced inflammation in animal studies.
Drinking milk with A1 beta-casein is linked to lower levels of glutathione in human blood and in the brain, liver, and gut of animals fed the same protein.
A1 beta-casein consumption is linked to higher levels of TNF-alpha in the gut tissue of animals.
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.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.