While breastmilk is typically considered the gold standard in nourishment, some babies may react negatively to it. We asked medical experts and lactation specialists to weigh in on what the underlying problem could be. Read on to learn more.
Stuart H. Agren, M.D.

Stuart H. Agren, M.D.

Dr. Agren is the Founder and Owner of AllergyEasy, which helps pediatricians and other primary care physicians around the country treat their patients’ allergies using sublingual immunotherapy. This is a safer, more kid-friendly version of allergy shots that involves daily drops under the tongue.

Food Proteins Pass from Mom to Baby

In my 35+ years as an allergy doctor, I have not heard of a baby being allergic to mother’s milk.  Rather, they may have sensitivities to something that Mom is eating that is upsetting them.  The proteins in allergenic foods can pass from Mom to baby and cause symptoms like spitting up, gas, and cramping, which results in a very sad baby.  Common culprits in a mother’s diet are cow’s milk and soy.

You can keep a food journal to try to identify what you are eating that is coinciding with your baby’s upset tummy, but keep in mind that there’s sometimes a delayed effect, so this may not be an exact science.  You can also talk to your doctor about trying an elimination diet to see if changing your eating can relieve your little one of discomfort. If your little one has ongoing food allergy problems, consider asking about sublingual immunotherapy, which involves taking daily oral drops that help desensitize the body to the food proteins that trigger allergies.

Sensitivities to Dairy Products in Mom’s Diet

Breast milk sensitivity is not very common. The baby may be sensitive to specific foods in the mother’s diet. The most common sensitivity is due to mothers ingesting milk, yogurt, and cheese.

Other sources of milk products can also be whey and casein added to processed foods. Other sensitivities may be due to other proteins such as soy, soy products, and eggs. Less commonly nuts, peanuts, eggs, wheat, pork, fish, and shellfish may cause sensitivity.

Symptoms of breast milk sensitivity include spitting up, diarrhea, fussiness, skin rash, and hives. Symptoms can develop from immediately after a feed to several hours after.

If a baby has a milk-protein allergy, and mom gives up dairy, why do they still struggle to seem comfortable?

Babies may not have a milk protein allergy. Rather, the baby may have a sensitivity to something else in the mother’s diet. Soy is the second most common cause of breast milk sensitivity. Soy is present in many processed foods. If your baby has soy sensitivity, you will need to carefully check food labels for the presence of soy products.

Suggestions for the best formula options?

Before switching to formula, Mom may need to try an elimination diet to determine what food is the offending agent. The most common elimination diet removes milk products, soy products, and eggs. Babies with true milk or soy allergies will need to be put on a diet of a hydrolyzed elemental formula.

Hydrolyzed elemental formulas have proteins and sugars broken down making the formula more easily digested and less allergenic. You should check with your baby’s pediatrician before trying an elemental formula.

What else can a mother do if she wants to continue nursing? Is there a specific diet to follow?

If Mom wants to continue nursing, she may need to check for offending agents via a trial of an elimination diet. The most common elimination diet is a diet without milk products, soy, and eggs. The diet should be tried for 2-4 weeks. If mom is limiting milk and milk products, she should have another source of calcium and vitamin D, such as a multivitamin.

After a 2–4-week period of eliminating the food items, try resuming [them] one at a time. If the baby is symptomatic, you have your answer! Consult with your baby’s pediatrician if symptoms are persisting despite a trial of the elimination diet. Your baby may need to be seen by an allergist. Many babies outgrow cow milk protein intolerance by 12 months of age, and most outgrow it by 4-6 years old.

Pierrette Mimi Poinsett

Pierrette Mimi Poinsett

Dr. Pierrette Mimi Poinsett MD, Pediatrician, and consultant for Mom Loves Best, one of the most trusted parenting websites.
Marie Burke

Marie Burke

Marie Burke is the resident Baby & Infant expert at O’Flynn Medical, specializing in assisting Mums with any of their breastfeeding and breast-pumping queries.

Considerations with Formula Alternatives

The composition of breast milk is very fine, so there are a plethora of variables to consider. It’s quite common for babies to have a sensitivity to the protein found within dairy, so after breastfeeding, the baby can be left with gas, which leads to vomiting in some cases or diarrhea.

The formula isn’t always the correct option, however.  As some formulas are based on cow’s milk, they will create the same symptoms.

Mothers can remove dairy from their diet to see if it makes a difference; however, it will take up to 21 days for any traces of dairy to leave the system. Some babies will react positively to the change, whilst some may see no difference whatsoever. In this case, you may need to remove every trace of dairy in your system.

The good news is there are a huge number of formula options available now that have no cow’s milk presence. Soy formula is one of the most popular options and is becoming more and more common as people gravitate towards vegan diets. Organic soy formulas give babies all of their nutritional needs.

Similarly, goat’s milk formula is a wonderful alternative, mainly because it is the closest to human milk.  Studies have shown over the years it is far more easily digested by humans than cow’s milk. Babies that struggle with cow’s milk and cow’s milk formulas tend to have a far better feeding experience after switching to a goat’s milk-based formula, mainly because the fats and proteins found within the milk are incredibly similar to human breast milk, much more so than cow’s milk.

If this isn’t working for you, there are hypoallergenic options available. It’s extremely common that when a baby is allergic to dairy milk, soy intolerance will follow. Hypoallergenic formulas do not use any soy or dairy and usually are made up of a mix of vitamins, minerals, amino acids, vegetable fats, and more. Amino acids are known as the building blocks of protein and, therefore, are far easier for a baby to digest.

Effects Of Tethered Oral Tissues in Nursing

Babies often struggle with milk-protein allergies even when mom gives up dairy because usually the underlying root cause has not been addressed. The reason may be due to the tongue, lip, or buccal (cheek) ties, also known as tethered oral tissues.

This happens because the tongue is the organ responsible for the beginning of digestion. If tied, the body reacts with reflux and allergy-type responses.

It is highly recommended to see a dentist that specializes in tethered oral tissues. Additionally, an International Board-Certified Lactation Consultant (IBCLC) can further assist before and after a tongue-tie release.

Deb Roth

Deb Roth

Deb Roth of Tongue Tie Life.
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