All About Tree Nut Allergies

in Food Allergy, Peanut & Tree Nut
Published: August 19, 2010
Photo: Thinkstock

Tree nut allergies are one of the most common and fast-growing types of food allergies in North America today.

When someone with a tree nut allergy ingests their allergen, even a trace amount, that person is at risk of a severe allergic reaction, called anaphylaxis. An anaphylactic reaction includes more than one of the body’s systems, such as the respiratory tract, gastrointestinal tract, the skin and cardiovascular symptom.

Symptoms of an allergic reaction include tingling in the mouth, swelling of the tongue and throat, itchy skin or hives, difficulty breathing, abdominal cramping and vomiting. In a severe anaphylactic reaction, a person may experience a drop of blood pressure, loss of consciousness and even cardiac arrest and death.

One of the issues in managing tree nut allergies is that reaction symptoms can vary greatly. A person may have minor symptoms on one occasion, but anaphylaxis on a next exposure.

Because tree nut allergy reactions can be severe, it is important that a person with this allergy carry an epinephrine auto-injector (EpiPen or Twinject) with them at all times. Research has shown that a small number of people (about 9 per cent) may outgrow their tree nut allergies.


In Canada, 2009 statistics show that 1.14 per cent of the population is allergic to tree nuts, while in the United States 1.1 per cent of children have the allergy and 0.5 per cent of adults. Tree nut allergy is on the rise: the 2008 telephone survey in the U.S. that found 1.1 per cent of children are allergic to nuts, compare that to just 0.2 per cent of children reported as allergic to nuts in 1997.

More on Tree Nut Allergy Statistics

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