The immune system will do its best to get rid of the invader, just as it would a foreign virus or poison. Note that lactose intolerance is a completely different condition. With lactose intolerance, individuals cannot digest the milk sugar called lactose, because they lack the enzyme lactase. The two main components are whey and casein, and a child may be allergic to either or both. The casein is the curd that forms when milk is left to sour, and the whey is the watery fraction, which is left after the curd is removed.
Some patients retain the allergy throughout life.
Cow's milk allergy may be acquired later in life. No milk-free diet should be undertaken without the supervision of a dietician, who will provide a list of alternative products to ensure a nutritionally adequate diet, in order to avoid deficiencies. So this article therefore only provides general advice to follow. Milk substitutes in the form of soya or hypoallergenic whey and casein formulas may be given to young infants on the advice of the doctor. Unfortunately, they are very expensive.