As a new or expectant mom, you want to do everything you can to keep your baby happy and healthy. It’s natural to have questions about how your diet might affect your baby, especially when it comes to food sensitivities and allergies. While these are important topics to be aware of, the good news is that most babies thrive on their mother’s milk, even when they eat common allergens. In fact, true allergic reactions to foods passed through breast milk are quite rare.¹ This guide is here to help you understand what to watch for, when to reach out for support, and how to feel confident in your breastfeeding journey.

How Food Sensitivities or Allergies Happen When Breastfeeding

Some babies may show signs of sensitivity to certain foods their mothers eat. Common triggers include cow’s milk, eggs, and peanuts.^2,3 It’s important to know that babies aren’t allergic to breast milk itself, but to small amounts of food proteins that pass into mother’s milk from the offending food.^2,3

The transfer of food proteins through breast milk is a key mechanism by which babies develop sensitivities.^2,3 In rare cases, these proteins may cause a reaction in sensitive babies (often, but not always, when there is a family history of allergies). This can lead to IgE-mediated allergic reactions, with symptoms such as diarrhea, vomiting, eczema (dry patches of skin), and hives.^2,3 

What Parents Can Do if They Suspect an Allergy

If you think your baby may be reacting to something in your diet, the first and most important step is to talk with your baby’s healthcare provider. You may also be referred to a board-certified allergist who specializes in allergies and immunology.^2,3 These healthcare professionals can conduct a thorough evaluation, which may include a detailed medical history, physical examination, and allergy tests.^2,3
If a specific food is suspected to be causing a reaction, it should be removed from the mom’s diet if she is breastfeeding, or from the baby’s diet, if they have started eating solids. The Academy of Breastfeeding Medicine (ABM) recommends the following steps:³

1. Keep a Food Diary: Keep a detailed food diary for a few days, up to a week, noting any symptoms that your baby has after you eat certain foods. Review the diary with your healthcare provider to identify any patterns or potential allergens.
2. Eliminate Suspected Foods: The ABM recommends the continuation of breastfeeding, while eliminating dairy products first—such as milk, cheese, yogurt, ice cream—since these are the most common cause of allergic reaction or sensitivity in the breastfed baby. Pay close attention to food labels, as many packaged foods contain traces of dairy that can cause a reaction. Click on this link for more information on how to read food labels. This process should be done for at least 2 to 4 weeks, with improvements often seen within 70 to 96 hours (3 to 4 days).
3. Reintroduce and Eliminate: If symptoms don’t improve, you can reintroduce the food into your diet and eliminate another food/food group from the list of common allergens—soy, citrus, eggs, nuts, peanuts, wheat, corn, strawberries, and chocolate. Continue this process until you have found the offending food or all suspected foods have been tested. Note that fish and gluten-free foods should be avoided with the assistance of a registered dietitian nutritionist to assure nutrients are not missed in the mom’s diet.

Managing Food Sensitivities

1. Managing food sensitivities while breastfeeding usually involves dietary modifications for the mom. This may include removing specific allergens from your diet and finding healthy alternatives to make sure you’re still getting the nutrients you need. Support from healthcare providers, including registered dietitian nutritionists and allergists, is helpful as well. 
2. Parents should be educated on how to recognize and respond to allergic reactions, including the use of different medications, if prescribed. 
3. Support groups and resources from organizations such as the Food Allergy Research & Education (FARE) can provide additional guidance and support for managing food allergies.

Impact of Undiagnosed Food Sensitivities or Allergies on Mom and Baby’s Health

What If I Have Questions?

If you are interested in learning more, these Aeroflow classes expand on some of the topics discussed above:

• Ultimate Breastfeeding Prep
• Introducing Solid Foods

Want More Info?

For a directory of Aeroflow’s other Care Guides offering information on pregnancy, baby care, and more, browse our comprehensive list of titles:

References