Peanut and Tree Nut Allergy
The world of nut allergies can get pretty curious at times. Many nuts are misnamed or not categorized properly by definition.
Peanuts are not real nuts; they are “legumes” along with peas and lentils. Yet, you look for them in the store in the same spot as cashews and almonds. Coconuts are a fruit but they are usually placed in the list of tree nuts that could cause allergies.
Peanuts are among the most common allergy-causing foods. It is estimated that 1% of children have a peanut allergy. This can be difficult to work with because of the number of items that these can be included in.
A wide range of potential allergens
Though not always, people who are allergic to peanuts can have a tree nut allergy and vice-a-versa. About 30 to 60 percent of children with a peanut allergy will have a tree nut allergy. There are many types of tree nuts. Some of the more common ones include:
- Almonds
- Beechnuts
- Brazil nuts
- Cashews
- Chestnuts
- Coconut
- Filberts
- Hazelnuts
- Lichee nuts
- Macadamia
- Pecans
- Pine nuts
- Pistachios
- Shea nuts
- Walnuts
There are lots of foods that may have these as ingredients. Think confectionary, breakfast cereals, baked foods, energy bars, dressings, etc.
Being allergic to one or two tree nuts does not mean you will be allergic to all of them. Approximately 12% of people with one report having a second tree nut allergy. The strongest crossover allergies are seen between walnuts and pecans and pistachios and cashews. Many people find that they are allergic to a combination of different nuts, but not all. Work with your allergist to determine your exact allergies.
Sometimes people are scared by the word ‘nut’ in names for things that are not nuts. Nutmeg is a seed, not a nut. The spices nutmeg and mace are made from this seed. People who have a nut sensitivity to almonds may find cross-reactivity, but having a nut allergy does not necessarily mean you are allergic to nutmeg. Butternut squash is a fruit. It is difficult to know if the color butternut was named after the squash or the butternut squash named after the color. Water chestnuts are an aquatic vegetable from a grass-like plant. They just happen to look like chestnuts.
What is the body’s reaction when someone is allergic to nuts?
When someone who is allergic to a specific nut eats something containing it, their immune system mistakenly believes that this food is harmful. The immune system responds by attacking the “problem” and making antibodies to fight the “invaders”. So something that is essentially harmless is suddenly not considered so by the body. The antibodies trigger the release of histamines which can have multiple affects in our body.
The symptoms of any food allergy are much the same, as it is the same bodily reaction whichever the trigger. They range from skin reactions like hives to life -threatening anaphylaxis (a medical emergency, anyone at risk of such should always carry an epi-pen). More on these general symptoms can be found here.
Testing and Diagnosis
Work with your health care provider to determine if you have an allergy to specific nuts. Track what you eat and your body’s reactions in a diary. They may decide to have you do skin testing or blood testing. A skin reaction or a positive antibody test may determine the exact cause. When this testing is inconclusive you may need to try an elimination diet or a food challenge. Do not try these without medical supervision.