What Do I Need to Know About Tree Nut Allergies?

bowl of mixed tree nuts like cashews, walnuts, pecans and almonds

Did you know that tree nuts are one of the most common food allergens in Canada? For people who are allergic, avoiding tree nuts and foods that contain tree nuts while still eating a balanced diet is important.  Read on to get the facts on tree nut allergies.

What is a tree nut allergy?

A tree nut allergy is when the body’s immune system mistakes tree nuts as harmful. For some, tree nuts can trigger life-threatening reactions. Some people may be allergic to more than one type of tree nut. If you have a tree nut allergy, always speak to your allergist before trying new types of tree nuts.

What are tree nuts?

Tree nuts include:

  • Almonds
  • Brazil nuts
  • Cashews
  • Hazelnuts
  • macadamia nuts
  • pecans
  • pine nuts
  • pistachio nuts
  • walnuts

Peanuts are legumes and are not considered a tree nut. Learn more about peanut allergies here.

What are the symptoms of a food allergy?

Like other food allergies, having an allergic reaction to tree nuts can include any of the following symptoms:

  • Flushed face, hives or a rash, red and itchy skin
  • Swelling of the eyes, face, lips, throat and tongue
  • Trouble breathing, speaking or swallowing
  • Itchy skin
  • Anxiety, distress, fainting, paleness, sense of doom and weakness
  • Cramps, diarrhea, vomiting
  • A drop in blood pressure, rapid heartbeat and loss of consciousness (in extreme cases)

When is a tree nut allergy usually diagnosed?

Tree nut allergies can be diagnosed in childhood and adulthood.  However, they are most often diagnosed in early childhood. 

If I am concerned about tree nut allergies, should I delay feeding it to my infant?

No. There is not enough evidence to say that avoiding tree nuts will lower the risk of an allergy.  However, avoid whole nuts and chunky nut butters because they are choking hazards. Try smooth nut butters like almond or cashew, spread thinly on toast or crackers instead.  Speak with your doctor or dietitian if you have a concern about introducing specific foods to your baby.

Can a tree nut allergy be outgrown?

Not likely. Tree nut allergies in children are less likely to be outgrown compared to other common food allergies. 

What foods may contain tree nuts?

Foods and drinks that contain or often contain tree nuts include:

  • Marzipan
  • tree nut oils
  • pralines
  • nougat
  • spreads, like almond-paste spreads, cheese spreads and chocolate nut spreads
  • dairy-free imitation cheese products made from tree nuts
  • plant-based milks like cashew or almond milk 

Food products that possibly add tree nuts include:

  • baked goods

  • baking mixes, cereals, crackers and muesli
  • barbeque and pesto sauces
  • dressings and gravies
  • flavoured coffees
  • frozen desserts
  • granola bars
  • liqueurs like amaretto
  • natural flavourings and extracts, like almond extract
  • salads
  • snack foods like trail mix

What are other names for tree nuts?

Tree nuts can have many other names including:

  • anacardium nuts
  • hazelnuts (filberts)
  • nut meats
  • pinon
  • macadamia (queensland nut)

Note: this is not a complete list. Speak to your dietitian or allergist for more information.

Canadian guidelines require foods that have tree nuts to be clearly labelled. The ingredient list will say “contains: almonds, Brazil nuts, cashews, hazelnuts, macadamia nuts, pecans, pine nuts, pistachios or walnuts” if it contains these tree nuts. Also avoid products that warn they “may contain” tree nuts on their label. These products may have come into contact with tree nuts (through cross-contamination).

Is it safe to eat peanuts if you have a tree nut allergy?

It can be.  If you are only allergic to tree nuts, you can eat peanuts. However, some peanuts are cross contaminated with tree nuts when they are processed and manufactured.  Consult with your healthcare provider or allergist before consuming peanuts as part of your regular diet.

Tips for following a tree nut free diet

Keep these helpful tips in mind when following a tree nut-free diet: 

  • Look for the words “contains: almonds, Brazil nuts, cashews, hazelnuts, macadamia nuts, pecans, pine nuts, pistachios or walnuts” on the ingredient list. All tree nut-containing foods are now clearly labelled.
  • Read the label every time.  Food manufacturers often change ingredients used in their products without notice.
  • Avoid food product labels that say “may contain” or “may contain traces” of tree nuts on their label.
  • If you are unsure if a product contains tree nuts, contact the manufacturer. Many food packages have contact information on them.
  • Don’t take chances. Avoid foods that do not have a clear ingredient list or an ingredient that you are not familiar with.  This includes avoiding imported products, as they do not always have an accurate food label.
  • Be informed. Sign up for the Canadian Food Inspection Agency’s (CFIA) free email “Food Recalls and Allergy Alerts” notification service.
  • When eating out, ask if dishes have been prepared using tree nuts.  If you can, call ahead to see if nut-free dishes are available.
  • Instead of adding nuts to baking, try rolled oats, dried fruit or rice cereal for a satisfying texture.
  • Looking for a mid-day snack that’s nut free? Try this warm and satisfying baked cinnamon pears with oat topping.

How can a dietitian help?

A dietitian can help you plan a nutritious, balanced diet that is tree nut-free. They can also teach you the skills to understand food labels and choose healthy and safe options when eating out. Some dietitians will even walk you through the grocery store to show you how to compare food products. Connect with a dietitian today!

Bottom line

You can still eat a balanced diet if you have a tree nut allergy. If you aren’t sure if a product contains tree nuts, don’t take any chances. Carefully reading the ingredient list of food products every time is important to avoid an allergic reaction. 

You may also be interested in:

Food allergies and intolerances
Food allergies and babies
Understanding food labels in Canada

This article was written and reviewed by dietitians from Dietitians of Canada.

Last Update – November 2, 2021

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