A1/A2 protein explained

Approximately one third of protein in cows' milk is beta-casein which is comprised of 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.

Cows' milk A1/A2 beta-casein protein digestion

Cows’ milk A1 and A2 type beta-casein 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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The a2 Milk Company respectfully acknowledges the traditional owners of the land on which we live, work, and operate. We pay our respect to Elders past and present. 

*A1 and A2 proteins refer to A1 and A2 beta-casein protein types

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a2 Milk® comes from cows specially selected to naturally produce milk with only the A2 beta-casein protein type so may be easier on digestion than regular milk for some milk intolerant individuals when consumed as part of a healthy, varied diet.