How to Prevent Food Allergies in Babies
Food allergies can be a serious concern for parents - they certainly were for me when my three girls were babies in the early 2010s. If you are a parent or caregiver struggling with anxiety and lack of guidance around top allergen introduction - you are not alone!
Food allergies affect millions of people worldwide, with children being particularly vulnerable. While there is no guarantee that we can prevent food allergies, the best way to reduce your baby's risk of food allergy is to introduce allergenic foods early and if tolerated, continue to feed them regularly.
In this post, my goal is to describe to you what food allergies are, how to recognize them, and the steps you can take to reduce the risk of your child developing food allergies. Understanding and implementing the strategies for introducing food allergens early and often can empower you to nourish your child with foods that are not only healthy additions to the diet, but also help reduce the risk of food allergy in infants and children. Let’s get started!
Before we dive in, here’s something important to keep in mind...
During the process of starting solids and preventing food allergies, feeding your family can actually become easier when everybody eats the same thing (baby included). It just takes some planning, which is what I aimed to do for you in my new book! To learn more, order your copy today! This accessible, practical guide is the only starting solids book you will need.
What is a food allergy?
A food allergy is an abnormal immune response to certain foods. It happens when a person’s immune system misinterprets a component of a food (most often a protein) as dangerous and responds with an adverse reaction.
Typically, immunoglobulin E (IgE) antibodies trigger the release of chemicals in the body (such as histamines), which can cause an allergic reaction to food, causing symptoms ranging from mild to severe. A true IgE-mediated food allergy is reproducible, meaning that a reaction will happen whenever the offending food is eaten.
There are currently no cures for food allergies, but it can be reassuring to know that by the age of 5, there is a good chance that your child may outgrow some food allergies.
A food allergy differs from a food intolerance. Food intolerances involve different parts of the immune system and occur when the body cannot properly digest specific food components, such as lactose in dairy products or gluten in wheat. This can lead to symptoms such as bloating, gas, diarrhea, or stomach cramps.
Unlike food allergies, food intolerances are not life-threatening but can cause discomfort. While food allergies require strict avoidance of the allergen and may necessitate carrying medications like epinephrine for emergencies, food intolerances often require simply limiting or avoiding the offending food to manage symptoms.
Which foods cause an allergic reaction?
While over 170 foods are known to cause food allergies, nine foods cause over 90% of allergies. These include:
Fish
Tree nuts
Wheat
Shellfish
Sesame
What are the signs of food allergies?
As a pediatric registered dietitian, in my private practice and in interactions with parents on my social media accounts, I see a lot of anxiety about potential allergic reactions as well as which symptoms to watch for.
During a food allergic reaction, any of the following four organ systems can be affected: the gastrointestinal tract, respiratory system, cardiovascular system, and/or skin. Neurological changes are also possible during a reaction, including inconsolability and lethargy.
The most common signs of a food allergy can include mild symptoms like a few hives, mild to moderate itching around the mouth, vomiting, diarrhea, repetitive coughing, or stomach pain.
Signs of severe food allergy include generalized, widespread hives on the body, swelling of lips, tongue, and throat, difficulty breathing, loss of consciousness, sudden fatigue, or symptoms that affect more than one organ system. These may all indicate that the person is experiencing anaphylaxis, a severe and potentially life-threatening reaction.
Symptoms usually occur within a few minutes of the food being eaten, although some reactions can take up to 2 hours to emerge and, in rare cases, longer. It's important to recognize these symptoms and seek medical attention if you suspect a food allergy.
How can I tell if my baby is having an allergic reaction to food?
In babies, the most common signs of food allergy are rash and vomiting. It is important to note here that it’s normal to see an increase in gas and changes in the frequency, color, odor, and consistency of your baby’s stool when a baby starts solids. These changes don’t necessarily indicate food sensitivities or intolerances. In most cases, they resolve over time as the digestive system matures and adjusts to complementary foods.
What should I do if my baby has an allergic reaction during food introduction?
If you think your baby is having a mild or moderate allergic reaction, stop feeding the allergen immediately and contact your pediatrician, who may recommend taking a dose of cetirizine(Zyrtec) or diphenhydramine(Benadryl) and can refer you to an allergist for further evaluation.
If you see any signs of a severe allergic reaction, call 911 and request an ambulance with auto-injectable epinephrine. Epinephrine is the only medicine that can treat anaphylaxis, and it must be administered rapidly. Note that neither cetirizine nor diphenhydramine will treat anaphylaxis.
If your baby's only symptom is vomiting, it may be related to a food allergy; however, babies also vomit for a whole host of other reasons as well, such as overfeeding, an overactive gag reflex, viruses, and reflux. Talk to your pediatrician if you have concerns.
What is FPIES?
Another lesser-known cause of vomiting is food protein-induced enterocolitis syndrome (FPIES), a severe, non-IgE-mediated condition based in the gastrointestinal tract and sometimes referred to as “delayed food allergy” because it can cause severe vomiting 1 to 4 hours after a trigger food is ingested.
Cow’s milk, soy, rice, and oats are common trigger foods for FPIES. FPIES often develops during a baby’s first year of life when the baby is starting solids, and most children outgrow the condition by age 3 or 4.
Common Trigger Foods for FPIES.
** Talk to your pediatrician or healthcare provider if you have concerns about FPIES, vomiting, or any other symptom listed above so they can provide further guidance. **
What makes a child at high risk for allergies?
Currently, there is no internationally agreed-upon set of characteristics that define infants at high risk for developing food allergies. However, in a 2020 consensus document updating their current approach to food allergy prevention, the American Academy of Allergy, Asthma, and Immunology (AAAAI), American College of Allergy, Asthma, and Immunology (ACAAI), and Canadian Society of Allergy and Clinical Immunology (CSACI) agreed on the following:
1. Severe eczema is the strongest risk factor for food allergies.
2. Babies with mild to moderate eczema, a family history of allergic disease in one or both parents, or a known, previously diagnosed food allergy are all considered to be at some increased risk.
However, even if your baby doesn’t have eczema or any other obvious risk factors, it’s important to note that food allergies often develop in babies with no identifiable risk factors. In fact, the majority of the burden of peanut allergy comes from kids with no eczema or mild eczema!
You may be wondering, “Is my baby at high or low risk for developing food allergies?” If so, talk to your healthcare clinician. If your child is at high risk, it’s important to establish your child as a patient right away with a board-certified allergist who can discuss any need for screening on an individual basis; however, current research suggests that routine screenings before allergen introduction (blood tests, skin prick tests) are not generally required or recommended in high- and low-risk babies.
Can foods prevent allergies?
Yes. While there is no guaranteed way to prevent food allergies, research suggests that introducing allergenic foods like peanuts, eggs, and fish early in a child's diet (around 4-6 months) and continuing to feed them regularly helps reduce the risk of allergies. However, early, frequent, and consistent introduction of top allergens is most effective during a very short window of time during infancy.
Food allergies develop over time and can theoretically develop at any point in life, although most food allergies emerge during infancy or childhood. They affect about 8 percent of children worldwide. What we don’t know is exactly how food allergies occur.
Over the last 20 years, there have been many changes in food allergy prevention guidelines. In the early 2000s, the American Academy of Pediatrics recommended waiting to expose children to common food allergens until after 12 months, and sometimes after age 2 or 3 years of age.
We now have a better understanding of how to reduce the risk of food allergies from landmark studies like the 2015 Learning Early About Peanut Allergy (LEAP) randomized trial, which showed that early peanut introduction and consistent peanut exposure going forward in high-risk babies reduced the risk of peanut allergy by 86 percent, and the 2017 Prevention of Egg Allergy with Tiny Amount Intake (PETIT) trial, which was stopped early because it so successfully reduced the risk of egg allergy.
Can you stop food allergies during pregnancy?
During pregnancy, proper nutrition is crucial in supporting the health and development of both the mother and her growing baby. While eating a nutrient-dense and varied diet during pregnancy is recommended, there is currently no conclusive evidence that including or excluding certain foods during pregnancy prevents or contributes to the development of food allergies.
Can you prevent food allergies during breastfeeding?
Breast milk is the gold standard of nourishment for babies up to 6 months old, provides a wide range of health benefits for both baby and mom, and is recommended up to age 2 years and beyond if it’s working for both the baby and the family. However, there is currently no conclusive evidence that breastfeeding prevents food allergies specifically.
Can hypoallergenic formula help prevent food allergies?
Hydrolyzed infant formulas have not been shown to protect against food allergy development or food sensitization, so there is no need to use one from a food allergy prevention perspective unless, of course, your baby needs it for another clinical reason.
How do I introduce top allergens to my baby?
If your baby is in the high or moderate risk category for food allergies, talk to your pediatrician or allergist about early introduction of allergenic foods. For low-risk children, those without risk factors, and in most cases, even those who are high risk, introducing food allergens should be safe and fun!
** My new book provides a complete and easy-to-follow guide, 8 weeks of meal plans, and a collection of 80 family-friendly recipes to help prevent food allergies while starting solids. If you want to make the process of starting solids and preventing food allergies simple, safe, and stress-free, order your copy here.**
When you begin, familiarize yourself with the signs of a food allergy reaction. Stop feeding the food if you see any signs of a reaction, and consult your pediatrician if you have any concerns or questions.
Here are a few other helpful tips when introducing potential allergens:
Start with a healthy baby! Don’t introduce new foods when your baby is sick, miserably teething, or especially fussy. You don’t want to mistake illness for a food allergy reaction
Use age-appropriate forms of the allergen, such as thinned peanut butter, plain whole milk yogurt, and scrambled egg
Begin early in the day, well before a nap, when you can monitor your baby during and for a couple of hours after the feeding
Give baby just a small amount of the allergen to start, observe for 10 minutes, and if your baby has no reactions, work up to a full (infant-size) serving
Once you have seen that your baby tolerates a food well, continue to offer it at least twice per week - try to aim for about 2 teaspoons of the allergen food, such as peanut foods, or about one-third of an egg
Feel free to introduce a new top allergenic food each day or every other day if it works for you (waiting 3 days between introductions of a new allergenic food is an option, but not necessary, even for high-risk babies)
Can I use a commercial multiple-allergen product?
There are several commercial products currently available that aim to make early and frequent introduction of top allergens easier on caregivers. Some include multiple allergens in a cracker or bar that can be fed directly or a powder that can be mixed into a puree or liquid.
For now, none of these products have been endorsed by any of the major allergy organizations, and there are currently no peer-reviewed studies showing that they are effective, so do your best to stick with mostly real foods for both food allergy prevention and nourishment purposes.
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If you’re interested in learning more about how and when to integrate foods, determine portion sizes, and identify food allergies for your baby, check out my new baby-led feeding cookbook!
And if you're looking for personalized nutrition support for your babies or kids, I am currently accepting new clients in my virtual private practice.