What is Casein?

Cow ’s milk is one of the most nutritious natural drinks and is supplementing human diet in a big way, across all age groups. Milk is considered as a complete food as it contains all components of human nutrition.   Milk acts as a source of water, energy, and nutritional components like minerals, vitamins, minor biological proteins, enzymes, etc. The energy sources in the milk comprise carbohydrates (sugars), proteins and fats. Proteins constitute about 3.3% of the milk and contain all the essential amino acids.  Casein represents the most abundant protein in the milk constituting 82% of the total protein content of the milk.

The β casein is the principal type of protein in the cow’s milk, which contains all the nine essential amino acids, namely Phenylalanine, Leucine, Isoleucine, Valine,  Histidine, Tryptophan, Methionine, Threonine, and Lysine. This protein is formed of 209 amino acid sub units and exists in two different forms called   β1 and β2. The 67th amino acid is different in the two forms. In β1  67th, amino acid is histidine while in the  β2 form it is proline. Accordingly, there are two types of milk. The type of cow’s milk containing β1 casein is called A1 type and that with β2 casein called as A2 type of milk.  Research carried out on this aspect has reported the β2 form as the original form of β casein and the β1 form of β casein was produced due to some mutations  (genetic alterations) happened in the European and American cows.

Why is A2 Milk Superior?

The process of digestion of the β1 and β2  is not alike.  During the digestion of milk, β1   (present in the A1 type of milk) generates a small protein called β Casomorphin – 7 (BCM 7). The BCM 7 acts as silent enemy hampering digestion process and interfering with the normal physiological processes of several organs. This, in turn, affects the human health leading to multiple disorders such as irritable bowel syndrome, diabetes, heart diseases, neuromotor disorders, autism, etc. The β2 , on the other hand, acts as boon avoiding the risks of food allergy towards milk and milk products among people. However, more focused research and confirmatory studies need to be done on the detrimental activities of BCM 7 on human health.