Dr. Greene’s Answer:
People used to say children that young don’t have allergies, but clearly they do. About 6 percent have food allergies, more than one in 20. Most of these are allergic to only one type of food, but among those whose allergy is to cow’s milk, there is a higher chance that they will also be allergic to soy and perhaps to goat’s milk. The good news is that these children are very likely to outgrow these allergies, most by the first birthday and almost all who haven’t by age 3.
Formulas like Nutramigen or Alimentum are hydrolyzed so that there is very little cow’s milk protein and many babies will do well on them. Those who are very allergic could use Neocate, which has none. I recommend that babies get either breast milk or formula for the full first year.
If you breastfeed and your baby is allergic to both cow’s milk and soy, then you need to avoid both in your diet. This entails reading labels carefully since ingredients such as casein and whey contain cow’s milk proteins and are commonly found in processed foods. The Food Allergy and Anaphylaxis Network has a helpful guide for avoiding milk and soy-containing products (https://www.foodallergy.org/files/media/downloads/HTRLsheet201…).
Goat’s milk is closer to human milk than cow’s milk is, and in many countries it is used exclusively for infant feeding. The protein in goat’s milk is easier to digest than the protein in cow’s milk. If you are going to use goat’s milk, the biggest thing to be aware of is that goat’s milk is low in iron and certain vitamins, especially vitamin B12 and folate. Infants fed unfortified goat’s milk who do not get supplemented with iron and vitamins can develop anemia. The other big thing to be aware of is that a bacterium called brucellosis can occur in goat’s milk, so you should boil it before giving it to babies. For children over 1 year old, goat’s milk is probably better than cow’s milk, just not as readily available in the U.S.