Change is a key to human evolution. When man tampers with nature, the outcome can go either way-favourably or otherwise. The same applies to our food supply including milk and dairy. Industrialization and increased demand of milk has led to cross breeding and creation of new genetic variants.
Typically, cow’s milk may be classified as A1 milk (from high yielding cows) or A2 milk. This classification as A1 milk or A2 milk is based on the genes of the cow. Recently, a relationship between disease risk and consumption of A1 or A2 genetic variants has been identified. Studies suggest that milk from cows with A2 genes is far healthier than their A1 counterparts.
Evidence linking A1 milk to ill-health is building up. These include conditions like type -1 diabetes, cardiovascular disease (IHD), delayed psychomotor development among children, autism, schizophrenia, sudden infant death syndrome (SIDS) auto-immune diseases, intolerances and allergies. There are certain people who are at a higher risk than others. Those with digestive disorders like stomach ulcers, ulcerative colitis, Crohn’s disease, Celiac disease, on long term medication or antibiotic treatment, are at higher risk. This may also explain the growing sentiment against dairy and increased number of people opting for vegan diets.
Milk with A2 protein, on the contrary, is known to have several health benefits. Infact, the health benefits and virtues associated with dairy and milk in our traditional texts are accrued from the A2 milk. A2 milk has been shown to prevent obesity among children and adults, improve brain function, promote digestion and increase breast milk production in feeding mothers.
Most dominant cows of today possess A1 genes, while the low yielding Indian Gir cow, which is on the verge of extinction, possesses A2 genes. Human milk, goat milk, sheep milk and other species are ‘A2- like’. Interestingly, incidence of type-1 diabetes and heart disease is lower in populations consuming A2 milk.
Most milk contains a mix of A1 and A2 protein and is commonly referred to as ‘A1 milk’. Milk in which more than 99% of the beta-casein is the A2 variant is known as ‘A2 milk’. Milk in general is a good source of high quality proteins and fats, B- vitamins and calcium.
According to a 2014 scientific publication for New Zealand Food Safety Authority (NZFSA), changing dairy herds to more A2 producing cows and labelling of products containing A1 protein may significantly improve public health. More research is needed to investigate the A1-A2 hypothesis. Meanwhile, for the average consumer in India the quality of milk in itself is a concern with reports of adulteration and impurities growing by the day. Tighter regulations are certainly needed at the Government level. The only way out for an individual is to look out for organic milk, preferably, from traditional Indian (Desi) cows.