When your baby is breastfed and starts showing signs of a food allergy, it can be alarming and confusing. You might wonder if something in your breast milk is causing the problem. Although it’s possible for breastfed babies to be exposed to food allergens through breast milk, allergic reactions are not common.

The connection between breastfeeding and food allergies is a complex topic. This article explains some key facts for parents and caregivers so they can best care for their babies.

Understanding Food Allergies in Breastfed Babies

Breastfeeding offers many health benefits for your baby, including possibly lowering the risk of asthma, type 1 diabetes, and even food allergies. However, breastfeeding is not a guarantee against food allergies, either in early infancy or later.

About 8 percent of children under 5 years old are affected by food allergies. A food allergy develops when a baby’s immune system mistakenly identifies a particular food protein as harmful, triggering an allergic reaction. This reaction can happen even when the baby is exclusively breastfed, as some food proteins from the mother’s diet can pass through breast milk.

Food Allergies vs. Food Intolerances

Let’s differentiate between food allergies and food intolerances. A food intolerance involves the digestive system — not immune — and is generally less severe. However, it can be difficult to distinguish between food allergies and food intolerances in babies who are only breastfed. The symptoms of food allergy and intolerance in an exclusively breastfed baby may be similar and can include:

• ​​Signs of being in pain
• Loose, mucousy, or strangely colored bowel movements
• Colic — Extended periods of crying for no clear reason
• Gas
• Reflux — Food or drink coming up into the esophagus or mouth
• Eczema — A skin condition that causes inflammation and itching

It’s important to know that in a baby who is exclusively breastfed, a food intolerance is more likely than a food allergy. Although the symptoms of both can look very similar, it is extremely rare for a baby to have an allergic food reaction via breast milk.

Signs of a Food Allergy in Breastfed Babies

Recognizing the signs of a food allergy in your baby is the first step in managing it. Symptoms of an allergic reaction after a feeding include:

• Hives or rash
• Vomiting
• Reflux

Other symptoms could occur hours or days later, including:

• Blood in the stool (poop)
• Eczema

Anaphylaxis (severe, life-threatening allergic reaction) caused by food allergens in breast milk is extremely unlikely. Many medical professionals think it’s pretty much impossible for a baby to have an anaphylactic reaction to breast milk. This is because breast milk itself doesn’t contain allergens that cause anaphylaxis. However, small amounts of proteins from foods the mother eats can pass into breast milk, but these amounts are typically too low to trigger severe reactions like anaphylaxis.

Still, it’s important to know the signs of anaphylaxis, such as difficulty breathing, swelling of the lips or face, or a sudden drop in blood pressure. If your baby shows any of these signs, you should use an epinephrine auto-injector (such as an EpiPen or Auvi-Q), if prescribed, and seek emergency care.

Possible Food Allergies in Babies

If your baby shows signs of a food allergy, the first step is identifying the allergen. One of these common food allergens could be the culprit:

• Cow’s milk
• Soy
• Wheat
• Eggs
• Nuts
• Fish

Diagnosing a Food Allergy

If you’re concerned about food allergies or intolerances in your baby, talk to your pediatrician. Depending on your baby’s symptoms and your family history of allergies, they may refer you to an allergy specialist.

Consulting with an allergist helps identify and manage your baby’s food allergies. Allergists can perform tests, such as a skin prick test or blood test, to confirm which food allergens are causing the reactions.

An allergist may recommend an elimination diet, where you temporarily remove certain foods from your diet to see if your baby’s symptoms improve. Once the symptoms subside, you can gradually reintroduce foods one at a time to identify the specific food or foods that are causing problems.

Some MyFoodAllergyTeam members have had positive results with elimination diets.

“The only things that I ate were salad (with vinegar and oil), turkey, plain baked potatoes, and veggies. When I did this with my youngest, she stopped spitting up and having a croup after about a week,” one member shared. “Found out later that she had an allergy to corn, tomatoes, wheat, and soy. I slowly started adding other foods back in and she did great for the rest of the time breastfeeding. It is a frustrating process, but so worth it.”

Managing a Food Allergy While Breastfeeding

Once a food allergy is diagnosed, the primary treatment is to avoid the allergen. If you want to keep breastfeeding, you might need to remove the food causing the allergy from your diet. You might also need to supplement with a hypoallergenic formula that doesn’t contain the milk allergen if your breast milk supply is insufficient. Be sure to consult with your and your child’s health care provider when making these changes.

“So far, we know my little boy has a milk protein allergy and an oats allergy,” one MyFoodAllergyTeam member shared. “I’m breastfeeding, so I’ve been getting used to cutting it all out. It’s not been easy, but it’s worth it to have a happy, pain-free little boy.”

Introducing Solid Foods

Some evidence suggests that introducing solid foods into an infant’s diet as early as four months may reduce the risk of developing allergies and aversions. That said, the American Academy of Pediatrics recommends starting at about six months.

Talk to your child’s pediatrician, and allergist if they see one, about the best age and method for introducing solids. They may have specific instructions for how to introduce new foods. Depending on your circumstances, your doctor may recommend introducing foods like peanut butter in their office.

Preventing Severe Reactions

For babies with known food allergies, preventing severe reactions is a top priority. Always have a small-dose epinephrine auto-injector on hand if your baby has been prescribed one. Additionally, make sure to teach anyone who cares for your baby about the signs of an allergic reaction and what to do in an emergency.

Can Food Allergies Be Outgrown?

The good news is that some babies outgrow certain food allergies as they get older. According to the American College of Allergy, Asthma, and Immunology, some allergies, such as those to milk and eggs, are more likely to be outgrown. In contrast, others, like peanut or tree nut allergies, may continue into adulthood.

Your health care provider will likely monitor your baby’s progress and may periodically test for allergies. In some cases, small amounts of the allergen may be reintroduced into your diet under medical supervision in an oral food challenge to determine if your child can tolerate that food.

The Importance of Breastfeeding Support

Managing food allergies while breastfeeding can be challenging, but you don’t have to do it alone. Lactation consultants, pediatricians, and allergists can offer valuable support and advice. They can help you navigate the confusing parts of diet, breastfeeding, and your baby’s health to ensure the best outcomes for both of you.

Talk With Others Who Understand

On MyFoodAllergyTeam, the social network for people with food allergies and their loved ones, more than 41,000 members come together to ask questions, give advice, and share their stories with others who understand life with food allergies.

Are you a caregiver for a breastfed baby with a food allergy? Share your experience in the comments below, or start a conversation by posting on your Activities page.