There is a current debate going on about A1 versus A2 milk. Take a look.
“Epidemiological evidences claim that consumption of beta-casein A1 milk is associated as a risk factor for type-1 diabetes, coronary heart disease, arteriosclerosis, sudden infant death syndrome, autism, schizophrenia etc. A broad range of studies from American and European investigations has shown reduction in autistic and schizophrenic symptoms with decrease in A1 milk intake. Further, animal trials have also supported the linking of type-1 diabetes to milk exposure in general and A1 beta-casein in particular.” (Indian J Endocrinol Metab. 2012 Sep-Oct; 16(5): 856.)
How did A1 beta-Casein become widespread in certain countries? At least a couple thousand years ago, natural genetic mutations in European cattle have caused the A1 beta-casein protein. Originally, all cows produced just the A2 beta-Casein protein. It is the BCM7 released from digesting A1 beta-Casein that proposed to cause the adverse health effects.
A2: goat, sheep, and native cattle of Asia and Africa
A1: Eurpeon countries and US
A2: Guernsey (the highest) and Jersey breed (these breeds only have A2)
A1: Holstein and Friesian breed (these have equal proportions of A1/A2)
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