And you’re not alone: About65 percentof people have a reduced ability to digest lactose after infancy.

Casein protein is slower-digesting than whey, and they both pack in all nine essential amino acids.

What is the difference between A1 casein and A2 casein?

Milk

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“Northern European cows suffered a spontaneous genetic mutation and began making A1 casein.

How can you tell if A1 is causing your dairy intolerance rather than lactose?

“Caseins are protein, whereas lactose is a sugar,” Dr. Gundry says.

These results were published in the American Heart Association’s journal,Circulation.

How can you test for A1 intolerance?

Can I still eat dairy if I am A1-intolerant?