Milk has been regarded as nature’s perfect food, providing an important source of nutrients for developing babies, growing children and for expectant moms. So many of us feel good about ourselves when we eat our Greek yogurt and drink our healthy kefir drink. After all, it says it is nutritious on the container and contributes to our gut bacteria (lactobacillus, right?). Simply put, no. Yogurt and its cultures do not reach the intestines since it is destroyed by the digestive juices, as designed. Only spores or delayed released capsule products get to the gut. When you hear about all the wonderful probiotics being good for your gut, that is incorrect.
Milk can be separated into two components during the process of cheese production. Acidification of milk separates it into a solid component (the curd, from which most cheeses are made) and the liquid component, the whey.
The whey is a mixture of various proteins, minerals, fat and water. Ricotta cheese is produced from the whey and is rich in whey protein.
The curd dominant protein is Casein of which there are four types. The βeta casein is the second most abundant protein, and the most important, and has excellent nutritional balance of amino acids. Bovine, or cow, βeta casein are broken down into 12 different types, A1-A12. Each one is structurally different, the two most important are A1 and A2 casein protein. Human milk is mostly A2 casein protein. The cow dominant protein was also A2 casein up to a few thousand years ago when a mutation (a change) occurred to form A1 casein in many of the cows. Even today, the dominant protein in northern Europe cows is A1; from France and south, the dominant protein is A2 casein. What is the big deal?
When we digest A1 casein protein, we generate a bioactive peptide called βeta-casomorphin-7 (BCM-7). This is not a good protein. It is a lectin that binds to sugar components of cell walls and can injure them. {Please see the section on Lectins-the antinutrient}. BCM-7 is suggested to be associated as a risk factor for human health hazards and potentially affects the nervous, endocrine and immune systems. It is also known to be an oxidant of LDL, believed to be important in the formation of arterial plaque.
There is evidence that consumption of βeta casein A1 milk is associated as a risk factor for Type-1 diabetes, coronary artery disease, arteriosclerosis, sudden infant death syndrome, autism and schizophrenia. Studies have shown that BCM-7 binds to the Beta cell of the pancreas and starts an autoimmune reaction against the pancreas to destroy the insulin making cells leading to Type-1 diabetes.
There is data showing that populations that consume milk containing high levels of A2 have a lower incidence of cardiovascular disease and type-1 diabetes.
Clearly, we need more studies to clarify these issues. At present, it would appear prudent to pay attention to what we eat and minimize the A1 casein protein consumption.
A2 can be found in all goat, sheep, buffalo (that’s right buffalo, not cow, mozzarella) and the following cows: Guernsey, Jersey, Charolais, and Limousin.
A1 cows: Holstein, Friesian, Ayrshire and British Shorthorn.