Lactose Deficiency in Infants

Abstract

to milk protein. Cow’s milk protein in the mother’s diet does end up in breast milk in sufficient amounts to cause symptoms in an intolerant baby. Babies being fed regular formulas, which are made from cow’s milk, are receiving large amounts of cow’s milk protein. It is believed that about 2% to 7% of infants have this problem, which, unlike lactose intolerance, tends to go away. (Many babies outgrow cow’s milk intolerance by the age of 6 months, even more by 1 year of age, and nearly all by the time they are 2.) Many, but not all, babies who are intolerant to cow’s milk are also intolerant to soy—approximately 20% to 30%. This means, though, that the majority of babies with this problem do just fine when there is no longer any cow’s milk protein in their mother’s milk or, in the case of formula-fed infants, when they are switched to a soy formula. For those who react to soy, other, more specialized (and more expensive) formulas are available. Actual allergy to cow’s milk protein is less com