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Your Quick Guide to Allergies in Breastfed Infants

Knowing how to look for the differences between intolerance and allergies in breastfed infants is important.
Photo: Airman 1st Class Austin Harvill, US Air Force Release. The appearance of U.S. Department of Defense (DoD) visual information does not imply or constitute DoD endorsement.

People seem to get all messed up with allergies in breastfed infants, but give me three minutes of your time, and I’ll get you mostly straightened out.

What is an allergy?

An allergy is the body’s exaggerated response to a foreign substance.

But, don’t confuse food intolerances with food allergies because they’re different. Here are major differences:

  • number of exposures required
  • the involvement (or lack of involvement) of the immune system
  • volume of the offending foreign substance needed to trigger a reaction

Also, the manifestation can be different. But hold on, I’ll get there!

What is the allergic process?

Here’s a simplified explanation of the allergic process. First, there’s an exposure to the antigen, which is the offending substance. Next, the body says, “WHOA! Some foreigner just invaded me!” As a result, the body builds special antibodies. Think of these as uniformed “special forces” warriors who are ready to fight the next invasion.

Often, the first exposure goes unrecognized because it occurred through the placenta, or through the mother’s milk.

It’s noteworthy that if it’s a food intolerance, there’s no need for a second encounter, and no IgE-mediated reaction.

Onset/resolution of allergies in breastfed infants

Allergies can appear or disappear at any time in anyone. This is true from pediatrics to geriatrics! 

How do allergies manifest?

Allergies in breastfed babies manifest in the same way as anyone else. An allergy becomes obvious through one (or more) of these three systems:

  • Respiratory: Common examples are a stuffy nose, sneezing, trouble breathing.
  • Gastrointestinal: GI-related allergies are very common. Common examples are diarrhea, blood in the stool, and more.
  • Skin: “Rashes” — a completely imprecise term — are attributable to multiple allergens. Poison ivy, medications, metal, dyes, cosmetics, and all sorts of other things can cause skin “rashes.”

If the manifestation is in another system, it is a problem. However, that manifestation is not an allergy.

Is a dermatitis rash an allergy?

The suffix -itis means inflammation. Some experts say that contact dermatitis and atopic dermatitis are both forms of the “rash,” eczema. Regardless of the label, there are several similarities and differences between the two. However, two differences stand out in my mind:

  • Atopic dermatitis is fairly common on the face of infants who have eaten an offending food.
  • Contact dermatitis is more likely to occur in adults than children. It results from having contact with the offending substance (for example, laundry soap.)

Common allergens in breastfed infants

Allergies in breastfed infants are often blamed on one possible allergen, and that’s the food the mother is eating. That’s often inaccurate and unhelpful. There are multiple other allergens:

  • Environmental: Pollens in trees, flowers, and grasses.
  • Animal allergies: People sometimes forget that their babies —as well as anyone else — can be allergic to pet hair, dander, or urine. And, sometimes people forget that wool is an animal hair. I have much more to say about that as related to lanolin cream.
  • Insects: Although we may be aware that people are allergic to honey bee stings, other common culprits include yellow jackets, wasps, hornets, fire ants, and probably more.

What foods are offenders for infants?

Remember, common “offenders” could be explained as an allergy or an intolerance. For the moment, skip what to call it. Instead, move to the real question: what foods are common offenders for infants?

  • Cow’s milk protein is the big one. Cow’s milk protein, given directly (as in cow’s milk-based formula or milk fortifiers) or eating it and then breastfeeding your baby, is a common offender.
  • Wheat, egg whites, peanuts and other offenders are worth noting.

How can we help with allergies in breastfed infants?

First, don’t rush to blame food or breastfeeding.

The best way to protect babies from allergies is through exclusive breastfeeding for at least six months. Notice that’s exclusive breastfeeding.

Be aware if your child is at high risk for allergies.

If allergies in breastfed infants have been confirmed, does an elimination diet help? Quite possibly. Try to keep a food diary. You can go old school with a paper diary or use one of several apps.

Just remember that after starting an elimination diet, it can take up to 1-2 weeks before the baby has relief from his symptoms.

What I’ve written today may soon be outdated. We need much more science to help better understand food intolerances and allergies in breastfed infants.

How have you seen allergies in breastfed infants? Let me know in the comments section below!

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  1. Hélène Thiéry

    I have 8 years of experience.
    I have specialized myself in food intolerances in breastfed babies.
    First of all, I believe that food intolerances in babies je due to an IGG mediated sensitivity developed in the mothers body. You usually have a lack of mastication, a lack of denaturation of proteins in the stomach, a leaky gut and a falty immune System.
    You may have a deficit in fucosyl transferase that explains part of the situation.
    I search for specific IGG and take them out of the mothers diet for a certain time ( depending on the amount of IGGs in the mothers blood sample).
    It surprisingly works.
    If I repair the guts, I will not see new food sensitivity during the breastfeeding period. But, I have a few babies of mothers who have a genetic deficit who probably declare IgA mediated food sensitivities.
    Hélène Thiéry
    Midwife IBCLC
    Specialised in nutritional and functional medecine

    • Marie Biancuzzo

      Helene, thank you for your input. I don’t necessarily dispute your observations, but I want to reiterate that by definition, a condition that is immune-mediated is different from an intolerance. However, I’m less interested in the “label” or the “cause” and more interested in the “cure.” Sounds like you have identified some maternal foods that are offenders that, once eliminated, bring relief to the baby.

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