4 Common Food Allergies In Babies & How To Prevent Them?

It's #FoodAllergyAwarenessWeek and did you know that food allergies impact up to 1 in 12 children? We know that so many new and expecting parents wonder (and worry) about the possibility of food allergies in their little ones, but we're firm believers that knowledge is power, and the more you know the more in control (and calmer!) you'll feel as a parent. Whether you want to brush up on the most common allergies to look out for, learn what to do about them, and even how (or if) you can prevent them, we've got you covered. Our research team has pulled together some answers and insights that should help.

So quickly, what is a food allergy? A food allergy is when a specific food (or a protein in that food) triggers an immune response with an adverse reaction (basically, a response that’s not typical). It’s the body identifying something as harmful when it isn’t and causing a reaction to protect itself. In infants, the most common reactions to food allergies include hives, wheezing or coughing, swelling (of the face, lips, or tongue), vomiting or diarrhea, and skin rashes (such as dermatitis or eczema).

While it might feel overwhelming to consider all of the things your baby could be allergic to, it may help to know that there are only 8 foods that comprise about 90% of all food allergies, and in many countries, these foods must be identified on nutritional labels. We've identified all of these below, and highlighted the 4 most common food allergies in children that you should be aware of.

4 Most Common Food Allergies in Children

1. Peanuts

What to know: Peanut allergies are one of the most common allergies, affecting up to 8% of children. About 15 to 22% of children do outgrow their allergic reactions to peanuts during adolescence. It’s long been thought that a family history of peanut allergies can make children more likely to have them, and because of this, many women were encouraged to avoid peanuts during pregnancy or if breastfeeding, to avoid a potential allergic reaction in utero and in infants. However, research actually suggests that an early introduction of peanuts might have protective effects against these allergic reactions. 

What to do if your baby is allergic to peanuts: An expert panel from the National Institute of Allergy and Infectious Diseases recommends infants with a severe case of eczema, egg allergy, or both should have peanut allergy testing conducted and introduce peanuts as early as 4-6 months old.

Fun fact: If you’re not allergic to peanuts, you should feel safe consuming them during pregnancy. They contain a healthy dose of folate as well, so they can make a great afternoon snack!

2. Eggs

What to know: Egg allergies are another common food allergy in children, with rates ranging by region. What's important to know is that over two-thirds of children will outgrow an egg allergy by age 16. Since the proteins in the egg yolk and egg white are slightly different, it is possible that your child is allergic to one or the other, though egg white allergies are more common.

What to do if your baby is allergic to eggs: Heating eggs can alter the shape of their proteins, so foods that include fully cooked eggs may not trigger an allergic reaction. One study found around 70% of children with an egg allergy could tolerate eating biscuits or cakes containing a cooked egg. Some studies have also suggested that introducing children with an egg allergy to baked goods can help decrease the time it takes for them to outgrow it. But this is something important to discuss with your pediatrician.

3. Cow’s milk

What to know: Cow's milk is believed to impact 2–3% of babies and toddlers. What's good to know is that a cow milk allergy likely won't follow your little one into adulthood, because around 90% of children eventually outgrow a cow milk allergy by 3 years old.

What to do if your baby is allergic to cow's milk: If you're breastfeeding your baby, you may need to eliminate cow's milk and any foods that contain it from your own diet (this includes cheeses, yogurts, and ice cream). If you're formula feeding, it's important to note that most formulas are cow-milk-based but there are formulas that are not, and your healthcare professional should be able to recommend some options available to you.

Fun fact: One thing that surprises many new and expecting parents is that a cow's milk allergy is not the same thing as lactose intolerance, they're completely different conditions, in fact. Studies consistently show that lactose intolerance is extremely rare in babies, but that doesn’t mean they can’t be born with it. If this does happen, it’s called congenital lactose intolerance and babies usually show signs right away within the first few feedings as they are deficient in the enzyme lactase (which is required to break down lactose sugars found in milk). There is also something called developmental lactose intolerance which can occur when a baby is born prematurely (before 34 weeks) since the enzyme lactase is generally produced later in the 3rd trimester. As their small intestine matures, babies often outgrow this intolerance.

4. Tree nuts

What to know: Tree nut allergies affect about 1% of the US and UK populations, and they are usually a lifelong allergic reaction that is not outgrown. Some examples of tree nuts include almonds, walnuts, cashews, pistachios, Macadamia nuts, pine nuts, and Brazil nuts.

What to do if your baby has an allergy to tree nuts: It's usually advised that if you’re allergic to one or two tree nuts to avoid all of them, even in trace amounts. Due to the effects of cross-reactivity, it's also recommended that if your child has a peanut allergy, they should avoid tree nuts and vice versa. We've got more on cross-reactivity below!

4 Other Common Food Allergies & How Cross-Reactivity Works

The four other common food allergies include wheat, soy, shellfish and fish. Soy and wheat allergies are also fairly common in children and these are often outgrown in adolescence, too. Shellfish and fish allergies, on the other hand, are actually quite rare in children. However, an allergic reaction to shellfish and fish can be more serious, so it's important to be aware of.

One final aspect of food allergies to keep in mind is the effect of cross-reactivity. An allergic reaction to a food is actually triggered by proteins in that particular food item. However, some proteins can 'look' really similar in related foods, and sometimes the immune system will react in a similar way as they would to what they are technically allergic to.

This can mean that your child could have a cow's milk allergy and also display an allergic reaction to goat's milk (due to the similarity of proteins). And as mentioned above, even though peanuts and tree nuts are from different families, there are enough similarities between them that can lead to a 'co-allergy' between the two.

Pollens can also cause a cross-reactivity allergic reaction in food! If you are allergic to certain pollens, you might experience an oral allergy reaction (often a raw or itchy mouth) when eating related fruits and vegetables. You may think you are allergic to that particular food item, but it's actually the pollen proteins that your body is reacting to. For more on the subject of cross-reactivity, here's a great read from Kids With Food Allergies.

Can You Prevent Food Allergies In Children?

There is no surefire way to prevent food allergies, but that doesn't mean you can't take steps to potentially reduce the risk of your child developing one! We've poured through the research on our end to bring you the top highlights:

When it comes to your prenatal diet:

Current research does not support excluding cow’s milk, eggs, and peanuts during pregnancy or breastfeeding to reduce the risk of food allergy and there aren’t specific recommendations to confidently prevent allergies for babies in utero.

When it comes to your maternal diet:

In a systematic review of maternal diets, researchers found that a Mediterranean diet pattern and diets high in fruits, vegetables, fish, and foods containing vitamin D was associated with lower risk for allergies in children. Diets associated with a higher risk of food allergies included vegetable oils, margarine, nuts, and fast food.

When it comes to your child's diet:

It is recommended that common allergenic foods be introduced early on in a child's diet (usually before 1 year of age). This is definitely something we recommend talking to your pediatrician about before doing, so that you have their guidance and support in the process. You'll want to be prepared to share any family history of food allergies with them as well. As an additional resource, Healthline has outlined steps for introducing high-allergenic foods to your little one that you can reference, here.

The interesting role of gut health and probiotics

Recent research has been published looking at the promising role of probiotics to treat peanut allergies (specifically, for now). Since probiotics contain “good” bacteria that help keep our gut healthy and bowels moving appropriately, the idea is that they may also help the digestive system better tolerate peanuts without producing an allergic reaction. 

In the original study, researchers gave a combination immunotherapy treatment of probiotics with small doses of peanuts. Researchers followed these children for 4 years after treatment, and found that 67% who were treated were able to eat peanuts without adverse reactions, while only 4% of those in the control group were able to eat peanuts without an adverse reaction. However, since this is such a small study, more research is needed to understand the role probiotics play in allergy prevention.

If you have additional questions on food allergies in children, please leave them in the comments below and we'll work with our experts to bring you the answers you need most.