A1/A2 protein explained
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A1/A2 protein explained

Beta-casein comprises approximately one third of the protein content in cows’ milk and most regular milk contains both A1 and A2 beta-casein. These have different outcomes upon digestion when compared to one another due to a slight difference in the amino acid sequence on the peptide chain. A1 beta-casein preferentially releases the opioid peptide beta-casomorphin 7 (BCM-7) on digestion. In contrast, the structure of A2 limits the release of BCM-7 on digestion.

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Cow’s milk A1/A2 beta-casein digestion protein digestion

Cows’ milk A1 and A2 beta-casein type protein digestion infographic

An infographic providing an overview of the A1 and A2 beta-casein protein variants. The graphic displays how upon consumption of regular milk which contains A1 beta-casein protein, BCM-7 is released resulting in gastrointestinal differences.

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