Milk Protein Allergy in Baby

Explaining Milk Protein Allergies in Babies


Is your baby colicky, fussy and seemingly uncomfortable most of the time? Does he or she have green, watery, frothy stools, or bowel movements with blood or mucous? Cow’s milk protein allergy may be the culprit. Research suggests between two and seven percent of babies younger than one year suffer from this complaint, making it one of the most prevalent allergies in this age group.

What Is It? Not to be confused with lactose intolerance, this allergy occurs when the immune system thinks the protein fraction of milk is a foreign body. This causes the body to produce the antibody, immunoglobulin E (IgE). When the antibodies find the “invader” (in this case cow’s milk protein), they attach to them and release inflammatory chemicals. These chemicals are at the root of the allergic symptoms.

What are the symptoms? An allergy to cow’s milk protein can cause colic-like symptoms, fussiness, an inability to settle or sleep, eczema, wheezing, vomiting, gassiness, diarrhea (including bloody diarrhea), constipation, hives, and/or a stuffy, itchy nose. Many babies with gastroesophageal reflux (GERD) suffer from a cow’s milk protein allergy, as well. Babies with this type of allergy often have weight gain issues, and tend to have green, watery, frothy bowel movements.

How is it diagnosed? To determine if your baby is allergic to milk protein, your pediatrician will take a thorough history and will look at your baby’s symptoms. He or she may order laboratory tests, including a stool and blood test. An allergy skin test may also be done where a small amount of the milk protein is inserted just under the surface of the skin. If a raised spot (which is called a wheal) emerges, your child may have a milk allergy.

What you can do? Any allergies in a baby can be challenging. Here are some practical suggestions for managing the disease:

  • Breastfeed: Allergies to something in mom’s diet are rare, and even when baby reacts badly to something mom eats, that offending substance can usually be eliminated from her meal plan in order to protect her baby. Breastmilk remains an important source of protection for babies with allergies – the immunities provided through breastmilk will keep baby healthier overall.
  • If your baby is formula fed, you may need to switch to a different formula. Keep in mind babies who react poorly to cow’s milk based formula typically have problems with soy formula, as well. Your baby will likely need a hypoallergenic formula.
  • Try an elimination diet: Elimination diets come in many different forms, but if you think cow’s milk protein allergy is at the root of your baby’s problem, you can begin by eliminating all dairy from your diet. Keep in mind that it can take 10 days to 3 weeks to eliminate cow’s milk protein from your system before you see any changes in your baby’s symptoms. It’s also essential to read nutrition labels and to identify “hidden” dairy. Many foods contain milk solids, whey or casein, for instance. You will need to eliminate any and all dairy ingredients to truly get rid of the proteins from your diet. If you have eliminated dairy from your diet, you will need to find alternative sources of calcium to maintain your own health. Good sources of this important nutrient include, fish such as salmon and sardines, fortified orange juice, and dark green vegetables (broccoli, in particular).
  • Hold the solids and introduce them gradually: Wait until your baby’s gut has had a chance to mature before introducing any solids, usually around six months. Once you are ready to get started, introduce one food at a time, so you can see how your baby’s system reacts. Researchers have found that six foods account for nearly all allergies in children. These include: cow’s milk, eggs, peanuts, wheat, soy, and tree nuts. Avoid these foods until at least age one (maybe even later for children with a family history of allergies).

Will my baby outgrow this? If you are on an elimination diet, you may be able to slowly add dairy back into your meal plan as your child gets older. Often it is trial and error – if your baby reacts badly, you will have to eliminate it again. If your child is diagnosed with a milk allergy, keep in mind most will outgrow the allergy by the time they are 3- to 5-years-old. For some children, however, the allergy is longer lasting, especially if either parent has a history of allergies.


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