Cow's Milk vs. Soy-Based
Cow's milk formulas contain lactose, the principal carbohydrate found in milk. Sometimes, when a baby develops bloating, cramps, vomiting, or diarrhea after feedings parents assume they are lactose-intolerant and need to change to a soy-based formula. However, symptoms of lactose-intolerance are very similar to symptoms of an allergy to milk protein. Changing formulas may not solve the problem and could cause your baby further distress. Consult with your child's doctor to find the underlying cause of any symptoms before making any changes in formula.
If your child is allergic to milk protein she may also have problems with soy protein. Studies conducted by the AAP show that up to 60 percent of infants with intestinal problems due to drinking cow's milk formula are equally sensitive to the protein found in soy-based formulas. For these babies, doctors may recommend a hydrolysate formula, commonly called hypoallergenic, an amino acid-based formula containing proteins that have been hydrolyzed (broken down). Never experiment randomly with different formula products trying to guess what might be best for your baby.