The casein of milk, is it different from that of cow, sheep or goat? How do each affect inflammation in the gut?

In recent years, around milk, especially cow's milk, several debates have been opened: if it causes allergies, mucus, if it is poorly digestible... One of the last is found around casein, the milk protein , of which he says that it can cause inflation and other health problems, especially if it is milk from cows.

Valentina Molina, dietitian-nutritionist, member of the Board of Directors of the Official College of Dietitians-Nutritionists of the Valencian Community (CODiNuCoVa), tells us what is true in some of the things that are said about casein.

What is casein and why is it said to be dangerous?

Casein is a protein present in milk, the most common, as it represents more than 82% of its proteins. The rest of the protein corresponds to whey. Within caseins, there are different types, and the most common is beta-casein, which in turn has two forms, A1 and A-2. Depending on the origin of the cows, their milk will contain beta-casein A1 (mainly cows from northern Europe, such as Holstein Friesians, Ayrshires and Shorthorns) or A2 (cows from the English Channel region and the south of France). , such as Guernsey, Jersey, Charolais and Limousin). A1 is due to a mutation that occurred about three thousand years ago, and is more common in modern breeds, and A2 is more common in ancient ones.

There are several studies that suggest that by digesting beta-casein A1, humans release a peptide called BCM7, which has been linked to health problems, such as autoimmune diseases (such as type 1 diabetes) or even autism. However, this would only occur if a person had a leaky gut, since it has not been shown that BCM7 can cross the intestine and reach the blood, nor has it been possible to establish a relationship between healthy adults and the prevalence of these diseases, as confirmed in this study.

What does seem to be more consensus is that A1 beta-casein produces more digestive problems and milk intolerance than A2 (in around 20% of people), but, as Valentina Molina states, “ It will depend on each person, not all of us adequately assimilate certain foods. But you always have to take individual cases into account and not generalize, since an intolerance, an allergy or an inflammation are not the same”. In other words, these digestive or tolerance problems do not occur in everyone, but only in those who are predisposed to it or who are allergic, something that occurs in a small percentage, "allergy to milk protein cow (CMPA) is more common during the first year of life (stage where the introduction of food begins) and affects 2% of children under 4 years old, "he says. In addition, in case of suffering from this allergy, the symptoms would be immediate, “food allergy occurs when the substance comes into contact with the immune system (in this case casein), and there is an immediate reaction. However, in food inflammation there is no immediate reaction, although the immune system is present, what develops is an inflammation when that particular food is consumed. Finally, food intolerance originates from our digestive system, which is due to the absence of enzymes responsible for breaking down said food · ”, she clarifies.

Is it better to drink goat or sheep milk than cow milk?

If we have a problem with casein A1, in principle yes, since, as they say in a study carried out by the University of Granada, goat's milk contains, in addition to beta-casein A2, "less casein type alpha 1 as it happens in women's milk, which are responsible for most allergies to cow's milk. Therefore, it is hypoallergenic. In the case of sheep's milk -or cheese-, the same thing happens, which contains beta-casein A2, which is the one that produces the least allergies. Even so, if we have an intolerance or allergy to milk protein, it is best to avoid any product that may contain casein, whatever its origin, “since it is a protein that is mainly present in mammalian milk and also in human milk. . For this reason, they should mainly avoid dairy products and their derivatives, but it can also be found in ultra-processed products such as chocolate, nougat, juices, cereals... in addition, some sausages or preserves. For this reason, it is important that people read the ingredients section (back of the package) to find out. Note that casein, being an allergen, will appear in bold due to the Food Labeling Law”, warns Valentina Molina.

Regarding digestive problems caused by milk, Valentina does not recommend the milk of one animal over another, although “there are options or alternatives that digest them better. An example can be vegetable drinks, although we must know what we buy. It is important that in the ingredients there is a percentage of 14% or 15% of the vegetable, be it soybeans, rice, almonds, among others. Even so, it would be advisable to consult with the appropriate professionals such as the Dietitian-Nutritionist to study the case and help you with eating habits and their alternatives”.

You also have to be careful with sports supplements, since casein is also sold as one of them, “in some studies, it has been seen that consuming casein has certain benefits for muscle recovery. Even so, when a type of supplementation is carried out, it is appropriate that it be supervised by a professional such as the Dietitian-Nutritionist specialized in sports. In addition, it must be taken into account that supplementation should not be generalized to the entire population, which is why it is very important that each person is studied based on their needs, since a high-performance athlete who has to achieve goals than a person who plays sports to maintain a healthy life”.