Types of Allergies: Tree Nut Allergy

Tree nuts—cashews, hazelnuts, pecans—are delicious snacks that are eaten alone as well as introduced into many main dishes and desserts. It’s not easy living with a tree nut allergy. Your allergic reactions can range from mildly annoying to severely distressing. In fact, a tree nut allergy is one of the most common causes of life-threatening food reactions. The good news is that you can learn to detect and safely avoid tree nuts while enjoying a delicious and satisfying diet.

How Will I Know If I Have a Tree Nut Allergy?

If you have a tree nut allergy, your immune system overreacts to the proteins in the specific tree nut and makes antibodies against the proteins to remove them from your body. As a result, your body makes histamine and other chemicals that cause widespread swelling and inflammation.

You might have a tree nut allergy and should call your doctor immediately if you notice any of these symptoms after eating tree nuts:

• Diarrhea

• Itching

• Nausea and vomiting

• Rash

• Runny or stuffy nose

• Stomach ache or abdominal pain

The following symptoms warrant a 911 call for immediate emergency care:

• Dizziness or passing out

• Hives, which are large areas of raised welts on the body or face

• Hoarse voice

• Shortness of breath

• Tingling, tightness or swelling of the throat, tongue or lips

• Wheezing, a high-pitched whistling sound made as you breathe

The only way to know for sure if you have a tree nut allergy is to see your doctor. To diagnose your symptoms, your doctor will ask you questions about your medical history, eating habits, and your symptoms. He or she will perform a physical exam and run tests, including skin testing. This involves exposing a small area of your skin to different substances to see what causes your reaction.

Who Gets Tree Nut Allergies?

Tree nut allergy usually begins in early childhood. A little over 1% of the U.S. population reports an allergy to tree nuts, comparable to the percentage of peanut allergy sufferers (Source: AAAAI). It is unlikely that you will outgrow your allergy.

You are more likely to have a tree nut allergy if you have other food allergies, especially a peanut allergy, or if there is a history of allergies in your family.

What Foods Should I Avoid If I Have a Tree Nut Allergy?

If you are allergic to one kind of tree nut, you are likely allergic to other types of tree nuts and peanuts as well. You should avoid peanuts and all types of tree nuts including:

• Almond

• Beechnut

• Brazil nut

• Cashew

• Chestnut

• Coconut

• Hazelnut

• Hickory nut

• Macadamia nut

• Pecan

• Pine nut, also called piñon, and pinyon nut

• Pistachio

• Praline

• Walnut

In addition, tree nuts can be found in many unexpected places, such as in pasta and meat-free burgers. Your best plan for avoiding tree nuts is to readfood labels and ask about ingredients in prepared foods.

Look for and avoid the following items:

• Any type of nut butter, extract, flavoring, or oil, such as those made from almonds, pistachios, walnuts, or cashews

• Any ingredient that includes the word nut. This includes nut meal, nut pieces, nut paste, and artificial nuts

• Gianduja, a type of chocolate that contains hazelnuts

• Pesto, which contains pine nuts

• Nougat

Avoid foods that are “produced on shared equipment with nuts or peanuts.” If you are unsure about any food, avoid it until you check with your doctor.

What Are Some Good Tree Nut Substitutes?

If you have a tree nut allergy, you may have heard that you can substitute soy nuts for tree nuts. However, your tree nut allergy makes it more likely that you are also allergic to soy as well as peanuts. You should not try any substitutes for tree nuts until you check with your doctor about what products are safe for you. 

When Should I Call My Doctor?

If you think that you, or your child, have a tree nut allergy, consult your doctor right away. Early diagnosis and treatment can help prevent serious reactions.

If you are diagnosed with a tree nut allergy, you should carry injectable epinephrine at all times. For serious symptoms, such as dizziness or shortness of breath, inject your epinephrine medication as directed. Call 911 even if your symptoms get better.