1 A1 Beta-casein, Type 1 Diabetes and Links to other Modern Illnesses

The role of milk and milk proteins in relation to human health remains controversial. However, there is a large body of evidence, reviewed in this paper, specifically linking A1 beta-casein to a range of illnesses. A1 beta–casein is produced only by cattle of European origin. The proportion of European cattle producing A1 beta-casein varies by breed and country. High levels are found in many parts of northern Europe and also other parts of the world where particular breeds of European origin predominate. Cattle that produce A2 and not A1 beta-casein are known as A2 cattle. A2 beta-casein was the original variant. A1 beta-casein releases bovine beta-casomorphin7 (BCM7) on digestion. The amount and stability of BCM7 that is cleaved from A1 beta-casein is linked to the presence and levels of various enzymes, in particular dipeptidyl peptidase 4. BCM7 is a strong opioid. There are seven strands to the evidence linking A1 beta-casein and BCM7 to Type 1 diabetes. These include particularly strong correlations amongst developed countries between A1 beta-casein intake and Type 1 diabetes incidence (r2 =0.84, p<0.00001)