Milk is a complete food as it contains all essential micro-nutrients needed for growth and development of human health as well as for neonate animals. However, milk derivative peptides may cause deleterious effect on human health by elevating risk for type I diabetes (DM-1), coronary heart disease (CHD), schizophrenia and autism. The higher occurrences of these diseases have relationship with consumption of variants A1, B and C beta–casein from cow’s milk. The production of BCM-7 is more in A1 milk than A2 milk and the difference is basically at 67th position of the beta casein chain. Due to presence of histidine at amino acid at 67th position, digestion of A1 β-casein milk releases a 7 amino acid bioactive peptide called β-casomorphin 7 (BCM-7) in small intestine, while proline in A2 milk at 67th position prevents splitting at this particular site. So propensity is now towards consumption of A2 milk. It is a matter of great concern for the health of people in India.

Keywords: A1 Milk; A2 Milk, Bcm-7; Proline Amino Acid; Histidine Amino Acid.