Let’s talk introducing allergenic foods. It’s kind of a scary thing to do as a parent, right? I mean, do you just feed your child the allergen and cross your fingers? Or do you go the other direction and feed it in the parking lot of your doctor’s office as a safety precaution? And once you do give them the food, how do you know what’s normal and what’s not?

This post will give you all the info you need to introduce these foods with confidence!

It’s important to know that most families will not experience any issue introducing allergenic foods. In fact, only about 8% of children in the U.S. are diagnosed with a food allergy!

But even though many children eat these foods every day and don’t have any allergic reactions, let alone extreme ones, introducing the top 9 allergens is a good thing to read up on before you jump in. You really don’t need to be scared, it’s just good to be prepared!

The Top 9 Allergens

First thing’s first, you need to know which foods we’re even talking about here! The top 9 allergens are:

• Peanuts
• Tree nuts
• Eggs
• Milk
• Wheat
• Soy
• Fish
• Shellfish
• Sesame

When To Introduce Allergenic Foods

For at least the last decade, parents were told to wait until 12 months and older to introduce the top allergens to their babies. Specifically, we were told to wait until 12 months old for dairy, 24 months old for eggs, and 36 months for peanuts, tree nuts, and fish. But, a 2015 LEAP (Learning Early About Peanut) study turned this information on its head. The study found that kids who were frequently fed peanuts as babies had an 80% less chance of developing an allergy.

Now, we recommend introducing allergenic foods to your baby as soon as they start solids. For most children, this is around 6 months old. Introducing allergenic foods at this point in your baby’s development can actually reduce the risk of developing some food allergies! This applies especially to eggs and peanuts.

I always recommend starting with easy-to-eat foods that are not common allergens, like avocado, sweet potato, and banana. Then, once you’ve successfully introduced some solids, you can move forward with introducing allergenic foods.

If you want help with exactly what to feed your baby and how, check out Simply Solids, my quick-start guide to starting solids that will get you started easily (and reduce your worries about it, too)!

How to know if they are allergic?

Below I will discuss the symptoms you might see for a peanut allergy, but these are symptoms that could occur with any allergy. If you notice any unusual symptoms that you think could be related to something you fed them, stop feeding that food and call the pediatrician.

Most times a severe reaction does NOT occur with the first exposure to the food. But reactions can get more severe with subsequent exposure. So do not feel like you’re being too extreme by calling the doctor if you notice a rash or itching.

Sometimes foods will irritate the skin WITHOUT an allergy. Acidic foods like berries, tomatoes, and citrus are known to cause a rash around the mouth or on their bottom. However, it’s best to get it checked.

Introducing Peanuts

Whether it’s because you know another child who had a terrible reaction right away, or because you’ve heard that lots of kids are allergic to them, introducing peanuts can be really scary! But I really don’t want you to feel too freaked out about this if you can manage it. Kids eat peanuts for the first time every day, right? 

That said, it is always good to be prepared, so here’s how to take the leap:

How To Introduce Peanuts

1. Serve them for the first few times at home, and not right before a nap time or bedtime
2. Mix about 2 teaspoons of smooth peanut butter with a serving of oatmeal
3. Start with just a bite or two, then wait 10 minutes to observe any reaction
4. If your baby has no reaction, feed them the remainder of the food containing 2 tsp of peanut butter, and observe them for a reaction
5. If there’s still no reaction, continue frequent exposure through 12 months of age, serving 3 or more times per week

What To Watch For

Mild peanut allergy symptoms can include:

• A new rash around the face
• A few hives around the mouth or face

Severe peanut allergy symptoms can include any of the following (alone or in combinatIon):

• Lip swelling
• Vomiting
• Widespread hives on the body
• Face or tongue swelling
• Difficulty breathing, wheezing, or repetitive coughing
• Change in skin color (pale, blue)
• Sudden tiredness/lethargy/seeming limp

If you see signs of a severe peanut allergy, seek medical attention. (But just remember, most families will not experience any issue introducing peanuts, or other allergenic foods!)

Safe Ways to Serve Peanut Butter to Babies

• Spread a thin layer on a toast strip (it’s too thick on its own and can be a choking hazard)
• Stir it into oatmeal or yogurt
• Mix it with roasted or pureed veggies (it’s so good with carrots!)
• Stir it into applesauce
• Mash it up with banana
• Use it in a curry
• Make a peanut sauce for noodles

You can also use other nut butters (like almond, cashew, or walnut) in addition to peanut butter, to introduce tree nuts!

Introducing Milk

Did your pediatrician ever tell you that your baby cannot drink cow’s milk?

Well, this is true in that cow’s milk should never replace breastmilk or formula before your baby turns 1. But, milk is actually not completely off limits! Your baby can have milk when it’s in other foods. You can feel free to bake with milk, stir a little into oatmeal, and serve other dairy foods like yogurt and cheese. 

And, you do not have to wait until your baby reaches a certain age to start introducing dairy. Yogurt is a great food to introduce, even right after they start solids!

Introducing Fish & Shellfish

Fish is such a healthy choice for babies! It’s typically a nice soft texture that they can easily manage, and it’s a good source of protein, omega-3 fats, vitamins, and minerals. Don’t be afraid to introduce fish to your baby, even if you don’t love it.

My top choices for baby are:

• Salmon
• Light tuna (but avoid albacore, it’s too high in mercury)
• Sardines
• Shrimp (I sliced shrimp lengthwise for my kids when they were babies so they could grab on and gnaw away.) 

Most babies also love canned salmon, tuna, or sardines mashed up with some avocado or mayo.

If you have older kids at home too, check out my post on seafood for toddlers! It has some of my favorite tips and kid-friendly recipes that I think you’d love. 

Introducing Eggs

When introducing eggs to your baby, follow the general guidelines on when to introduce allergenic foods that I outlined above. There are no particularities with this one, so you can just go for it once they’re happily eating solid foods. Just be sure to serve baby-friendly portions so the eggs don’t become choking hazards– especially if you’re hard boiling them. When you’re just starting out, omelets are a great choice for babies!

I’ve had a few parents tell me that they’ve heard they should wait to introduce egg whites. Maybe you’ve heard this too! But let’s clear this one up for good: there’s no reason to avoid egg whites (or eggs in general) when feeding your baby. 

Introducing Wheat

Unless there are signs of an allergy or Celiac disease, there is no reason you need to avoid wheat or gluten for your baby. If you’ve heard otherwise, this is probably a huge relief! 

Again, once your baby is eating solids, It’s perfectly fine to introduce wheat products. I like to start with bread. Lightly toasted and cut into strips for easy grabbing is perfect!

Introducing Soy

I hear a lot of concerns from parents about soy, and that’s understandable. There are a lot of mixed messages out there about it and whether it’s actually healthy or not. 

Here’s the truth: we know from research that minimally processed soy products are perfectly fine to consume! That means they’re not related to problems with hormones or cancer. 

The healthiest sources of soy for you and your baby are:

• Soybeans (edamame)
• Tofu
• Tempeh
• Miso

So now that we’ve cleared that up, you can feel good about going ahead and introducing soy to your baby! As with all the other allergenic foods, follow the guidelines above for when to introduce and what to watch for, and you should be just fine.

Resources for starting solids:

• Simply Solids: the quick guide to introducing your baby to food
• My Favorite Baby and Toddler Feeding Tools
• 50 Best Baby Food Pouches [2023]
• The Ultimate Guide to Baby’s First Foods from 4-6 Months Old
• What to Order for Your Baby at a Restaurant
• Sodium Guidelines for Babies, Toddlers and Older Kids