Tree Nut Allergies

Along with peanuts and shellfish, tree nuts are one of the major food allergens most often linked to anaphylaxis—a serious, rapid onset allergic reaction that may cause death—and emergency department visits. Tree nut allergy is also considered to be lifelong in most tree nut allergic individuals; fewer than 10 percent of people outgrow it.

From the popular walnut to the lesser-known lichee nut, tree nuts come in various shapes and sizes. People diagnosed with an allergy to a specific tree nut may be able to tolerate other tree nuts, but allergists usually advise their tree nut allergy patients to avoid all nuts.

There’s often confusion between peanuts and tree nuts. Peanuts, which are legumes, are unrelated to tree nuts. However, research findings have indicated that 28 percent to 50 percent of patients who are allergic to peanuts also react to at least one tree nut.

Tree nuts are commonly used as garnishes in salads, as a featured ingredient in Asian dishes, and as an ice cream topping. They may also be found in baking mixes, breading, sauces, desserts, and baked goods.

Tree nut allergies in children

Tree nut allergies among children significantly increased in the last decade. According to a recent study, there was a fivefold increase in the number of children in the United States with self-reported tree nut allergy, from 0.2 percent in 1997 to 1.1 percent, or 820,069 American children under the age of 18, in 2008.

 Frequently asked questions

If you have a tree nut allergy, do you need to avoid peanuts?

Even if they are not allergic to peanuts, people allergic to tree nuts are often advised to avoid peanuts as well because of the probability of cross-contact between tree nuts and peanuts in facilities that process foods. Talk to your allergist about whether or not you should avoid peanuts.

Should someone with a tree nut allergy avoid coconut and nutmeg?

Coconut is not a botanical nut; it is classified as a fruit, even though the Food and Drug Administration recognizes coconut as a tree nut. While allergic reactions to coconut have been documented, most people who are allergic to tree nuts can safely eat coconut. If you are allergic to tree nuts, talk to your allergist before adding coconut to your diet.

Nutmeg is a spice that is derived from seeds, not nuts. It may be safely eaten by people with tree nut allergy.

Revised and reprinted with permission from the American College of Allergy, Asthma & Immunology