Peanuts and eggs get all the hype when it comes to food allergies, but tree nuts are also one of the most common food allergies babies develop. And while many parents worry about peanut allergies when they start feeding their baby solid foods, most forget that tree nuts could also pose an allergy risk. 

In this guide, we’ll explain what tree nuts are, how they differ from peanuts, and how you can safely feed your baby tree nuts to reduce their risk of developing a food allergy. 

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Understanding Tree Nuts

In order to help reduce your baby’s risk of developing a tree nut allergy, it’s important to understand what tree nuts are and how they differ from peanuts. 

What are Tree Nuts?

Tree nuts are the seeds of fruit-bearing trees. But they’re not the same as peach or avocado pits. 

Think about a peach. The outermost skin is soft, and you eat the meat that surrounds the seed, also called the pit. In the case of a tree nut, you can’t eat the outermost layer, or the meat of the fruit. Instead, you eat the seed itself, which is also enclosed within a hard, inedible shell. 

There is also a big difference between peanuts and tree nuts. Peanuts and tree nuts are not related, as peanuts are a legume as opposed to an actual nut.

Tree Nut Families

When it comes to tree nut allergies, the family the tree nut comes from plays a big role in determining what other tree nuts might cause a reaction. 

Tree nuts from the same family often cause cross-reactivity between each other. 

The tree nut families and associated tree nuts are as follows:

Betulaceae: hazelnuts (otherwise known as filbert nuts) Juglandaceae: walnuts and pecans Rosaceae: almonds Anacardiaceae: cashews and pistachios Lecythidaceae: brazil nuts Proteaceae: macadamia nuts Pinaceae: pine nuts

People who are allergic to walnuts are more likely to be allergic to pecans because they come from the same tree nut family. Same with cashews and pistachios. 

Tree Nut Allergies

Tree nut allergies develop when your baby’s immune system falsely identifies tree nut proteins as harmful. Each tree nut produces its own proteins, so your baby can be allergic to one or multiple tree nuts. 

When the nut protein enters your baby’s body, their immune system tries to get rid of it. This is what we see as the symptoms of an allergic reaction: hives, swelling, vomiting, coughing, etc.

Are Tree Nut Allergies Genetic?

There is some genetic component to food allergies, but they are not 100% genetic.

Babies are more likely to develop food allergies if they have parents with food allergies, eczema, or asthma. 

Having a parent with:

  • Asthma or eczema doubles the rate of food allergies.
  • Seasonal allergies doubles the rate of food allergies. 
  • A food allergy increases the risk of developing a food allergy almost 6x. 
  • Two or three allergic conditions (asthma, eczema, food allergies, seasonal allergies) also doubles or triples the rate of food allergies.

Additional Causes of Tree Nut Allergies

Eczema, gut health, and an existing peanut allergy are the largest indicators for whether or not a baby will develop a tree nut allergy

Eczema:

Eczema is the biggest contributor to babies developing food allergies. The earlier a baby develops eczema, and the more severe it is, the more likely he will develop food allergies. 

Graph showing eczema severity and relationship to food allergies

In a study of babies with no, mild, medium, and severe eczema:

  • Babies who developed eczema by 3 months old and needed prescription strength medicines had a 50% rate of food allergy. 
  • Babies who developed eczema closer to 1 year old and needed only emollients had a 5% rate of food allergy. 

Eczema leaves breaks in the skin and allows food particles, like tree nuts, to get in. This causes your baby’s immune system to go on alert about tree nuts, even if they haven’t eaten them before. 

Gut Health

Every person has a microbiome that consists of trillions of healthy bacteria that live in and on them. Having the wrong kind of microbiome bacteria or having too few bacteria can cause gut dysbiosis

In gut dysbiosis, the bacteria in your baby’s microbiome leave their gut weak or make it inflamed. This can cause leaky gut, which lets food particles pass into the bloodstream instead of being processed in the stomach. This can cause your baby’s immune system to falsely mark food likes tree nuts as harmful 

Existing Peanut Allergy

30% of babies with a peanut allergy also develop an allergy to one or more tree nuts. There’s no scientific connection between peanuts and tree nuts, but scientists believe that children who live in houses with peanuts are more likely to live in houses with tree nuts as well. 

Being around a food without eating it allows a baby to become sensitized to that food. While sensitization doesn’t confirm an allergy, it means your baby’s body has created antibodies ready to fight that specific protein when they encounter it the next time.

Preventing a Tree Nut Allergy

The good news for parents is that there are steps they can take to reduce their baby’s risk of developing a tree nut allergy. 

The single best way to reduce your baby’s risk of developing a tree nut allergy is to feed them tree nuts early and often.

The American Academy of Pediatrics Guidelines

After the LEAP and EAT studies proved that babies could cut their risk of peanut and other food allergies by 80% by eating those foods 3 times a week, the American Academy of Pediatrics released new guidelines advising parents not to wait until 3 years old to introduce nuts.

Doctors recommend practicing early introduction with peanuts and other allergy-causing foods to lower your baby’s risk of developing food allergies.

This applies to tree nuts, too. The tricky thing is that tree nuts encompass more than 8 different types of nuts. So what should parents do? 

Focus on the nuts that you keep in your house. This includes those protein bars with almonds and cashews you have in your salads. Babies are more likely to develop allergies if they are around foods that they are not eating. 

Feeding Babies Tree Nuts

If the tree nuts are prepared safely, babies can begin eating nuts as soon as they have tolerated one or two other solids like baby cereal, usually around 4-6 months old. 

The American Academy of Pediatrics outlines the following guidelines for babies to start eating nuts.

Infants 4- 6 month old at:

  • Low Risk: Babies no eczema, no known food allergies, and little family history of allergic disease, are at low risk of developing a tree nut allergy. They should start eating nuts regularly soon after they start solid foods. 
  • Medium Risk: Babies with mild eczema that responds to emollients or those who have a family history of food allergies or allergic disease are at medium risk. They should start eating nuts regularly soon after they start solid foods. Parents may want to speak with their doctor first, and even ask if a serving of nuts could be given at the 6 month well visit.  
  • High Risk: Babies with eczema that requires prescription drugs, a known food allergy, or both should see a doctor to get tested for an existing sensitization to nuts. 
    • Babies who are not sensitized should begin eating those foods 3 times a week starting between 4-6 months old. 
    • Babies who are sensitized, but pass a food challenge, should begin eating those safe nuts 3 times a week starting between 4-6 months old.

Only babies with a confirmed allergy should avoid that food. 

How to Feed Your Baby Tree Nuts

Whole nuts are a choking hazard for babies, nut meals often leave behind the skins which can get stuck in baby’s throat, and tree nut butters are often too thick for young babies. 

The safest ways to feed a baby tree nuts when they are 4-10 months old are to thin nut butters with formula or breast milk, or use Lil Mixins Tree Nut Powder Mixin.

  1. Mix 2 scoops or 1 packet of Lil Mixins Tree Nut Mixin into their food. It contains no added sugar, no salt, and is made from almonds, walnuts, hazelnuts, & pistachios
    Mixing in Lil Mixins to baby food
  2. Thin 2 teaspoons of almond / cashew / walnut butter with warm breast milk or formula. Allow the mixture to cool. Feed baby the nut soup or stir the soup into baby food.
    Mixing in two teaspoons of nut butter to baby food

Some nuts have the superpower of helping the body tolerate multiple nuts. Lil Mixins Tree Nut Mixin is made with almonds, walnuts, hazelnuts, and pistachios because studies have shown that eating those four can provide the training wheels for all tree nuts.

Signs and Symptoms of a Tree Nut Allergy

The first time you feed your baby any new food, do it at a time where you will be near your baby and able to monitor them for the next 2-4 hours. Allergic reactions usually occur within 2 hours of a meal, but can occur almost 4 hours after. 

Allergic reactions in babies look like: 

  • Redness around the mouth or skin that came into contact with the nut
  • Hives 
  • Stomach distress such as vomiting or diarrhea. 
  • Runny or stuffy nose, sometimes with clear discharge
  • Redness or itchiness of the nose
  • Swelling of the face, including puffiness around the eyes
Redness around baby's mouth from allergic reactionRedness around the mouth during an allergic reaction
Swelling under baby's eye during an allergic reaction

Swelling of the face and eye area from an allergic reaction

While more serious symptoms are very rare, serious symptoms of a tree nut allergy in babies include:

  • Coughing/wheezing
  • Difficulty breathing 
  • Swelling of the mouth, including the lips and possibly tongue
  • Fever higher than 101.4 degrees or lower than 97 degrees
  • Swelling of the throat and difficulty swallowing
  • Weak pulse
  • Losing consciousness 

What to Do If Your Baby Has an Allergic Reaction

If your baby has a mild reaction like hives or redness around the mouth, an age and weight-appropriate amount of Benadryl should reduce the reaction. Call your pediatrician’s office and stay with your baby. 

If your baby has a severe reaction such as coughing or wheezing, OR both skin symptoms and stomach symptoms, bring them to an urgent care or emergency room immediately for observation and help. 

 

Most parents don’t realize having two types of a mild reaction is considered a severe reaction. It means that your baby’s body is responding aggressively to the nuts, and a doctor should evaluate your baby to make sure the reaction has passed.

Living with a Tree Nut Allergy

Even after all the work of feeding your baby tree nuts early and often, it’s still possible for your baby to develop a tree nut allergy.

But the good news is tree nut allergies are easier to manage these days. If you’ve recently found out your baby has a tree nut allergy, the first step is to look at everything in your house, become acquainted with the foods that often contain tree nuts, and understand how to read food labels.

Avoiding Tree Nuts

Avoiding tree nuts is your best bet for minimizing accidental exposure. Here’s a list of foods that often contain tree nuts:

  • Walnuts & almonds are commonly added to cookies, pastries, and breads
  • Crumbled pistachio, macadamia and hazelnut create a crunchy topping on pastries
  • Many store-bought loaves of bread add in seeds & nuts
  • Many chocolates have versions with almonds or other nuts. Be wary of cross contamination.
  • Coffee, creamers and hot chocolate often have hazelnut
  • Almond milk is a popular milk alternative
  • Vegan cheeses and ice creams are made with nuts 
  • Cereals and granola commonly have tree nuts 
  • Trail mix
  • Energy bars use nuts for protein
  • Mediteranian cuisines use pistachios, almonds, and other nuts
  • Indian food uses cashew to create cream sauces
  • Thai / Chinese / Malay / Indonesian cuisine uses mostly peanut but can include tree nuts
  • Any food labeled as Vegan
  • Veggie burgers or other meat replacements
  • Sauces. Especially pesto and, mole sauce
  • Cooking oils

Food Allergy Labeling

The Food Allergen Labelling and Consumer Protection Act (FALCPA) was passed in the U.S. in 2004. This Act requires the presence of the eight major food allergens — milk, egg, fish, crustacean shellfish, tree nuts, wheat, tree nuts, soybeans — in any packaged food to be declared using a name that is recognizable in the ingredients list or in a “contains” statement.

Example of food allergy labeling

The FDA does not require manufacturers to declare if nuts are used or held in the same facility as the packaged food you are reading, but more and more companies are doing so to be transparent with their customers. 

Examples of cautionary labels include:

  • "May contain tree nut"
  • "Manufactured in a facility that uses tree nut ingredients"
  • "Manufactured in a facility which processes tree nuts"
  • "Processed in a facility that uses tree nut"
  • "Manufactured on equipment that processes products containing tree nuts"
  • "Manufactured on equipment that uses tree nuts"
  • "Manufactured in a facility that processes tree nuts, but not on the same equipment"
  • "Manufactured on shared equipment...may contain tree nuts"

Preventing Accidental Tree Nut Exposure

The best way to prevent accidental exposure is to be overly clear with the people who will be interacting with you or your baby’s food. 

Restaurants

Always tell your server about an allergy. Make sure the food you are ordering doesn’t substitute nuts. For example, pesto is usually made with pine nuts, but it can be made with other tree nuts like walnuts. Never feel uncomfortable asking about the ingredients or the way the utensils are cleaned. 

Food allergies are now a protected disability class under the American with Disabilities act, and every restaurant has to accomodate you.

Friends and Family Members

Give each person an emergency plan, and talk through it with them. Describe what food reactions have looked like in the past so they know what to look for. Bring food or give caregivers specific lists of brands you are comfortable with.

If you’re not 100% comfortable yet, do a trial run with family members where you can see what they feed your child or how they keep their area free of nuts.

Schools

Remember that each school wants to keep your child safe. Ask to set up a meeting to discuss your baby’s tree nut allergy and what she needs.

Most schools are required to create a 504 plan with parents. The goal of 504 plans is for children to be in the same classrooms with all other children, but with the services, changes, or help they need.

Bring an EpiPen Everywhere

It is critical for a baby with a food allergy to always have an EpiPen nearby. Allergic reactions can happen ANYWHERE. 

The Rules for Treating a Reaction

Every family needs to make, review, and agree on an action plan for allergic reactions with their doctor. Food Allergy Research & Education has an action plan any family can use and adapt to their circumstances.

The key to your action plan is:

  1. At any sign of a reaction, give your child Benadryl. Check out this chart for how much Benadryl to give depending on your baby’s age and weight
  2. If two body systems start to be involved in the reaction (like hives AND vomiting), use epinephrine and go to the ER.
  3. If any critical body systems are involved in the reaction (trouble breathing, drop in blood pressure) use epinephrine and call 911.

Whenever epinephrine is used, a child must go to urgent care or the ER. Your child may not need any more medicine after the epinephrine, but symptoms can worsen or improve over several hours after an exposure. Being near medical care will keep your child safe until they are in the clear. 

Babies Aren’t Born with Tree Nut Allergies

Tree nut allergies are preventable, and armed with the information from this guide, you should be prepared and confident in reducing your baby’s risk of developing a tree nut allergy. 

Starting an early introduction routine with tree nuts as soon as they start solids foods can significantly lower their risk of developing a food allergy. But even if one does develop, it’s easy for parents to navigate the world without tree nuts.