What causes a tree nut allergy

The most common tree nuts include macadamia nuts, brazil nuts, cashews, almonds, walnuts, pecans, pistachios, chestnuts, hazelnuts (filberts), and pine nuts (pignoli or pinon).

What causes a tree nut allergy

Less common tree nuts include beechnuts, butternuts, chinquapins, gingko, hickory nuts, lychee nuts, pili nuts, and shea nuts.

Children who are allergic to multiple types of tree nuts (more than one or two) are less likely to outgrow their allergy than children who are allergic to just one type of tree nut.

Treatments for nut allergy

If you or your kid has reacted to eating nuts, the first step is to see your doctor. They may send you to an allergy specialist who will do a skin or blood test to see what you are allergic to.

You may be allergic to several diverse types of nuts.

There is no cure for nut allergy. The only proven treatment is to completely avoid exposure to the nuts you’re allergic to.

What causes a tree nut allergy

Research is underway into how to prevent nut allergies in people who may be at risk, and how to ‘switch off’ nut allergy using immunotherapy.

If you are at risk of anaphylaxis, you may be given an adrenaline autoinjector (EpiPen). You should also own an anaphylaxis action plan so you and everyone else knows what to do if you are exposed to nuts.

What is a nut allergy?

A nut allergy develops when the body’s immune system becomes over-sensitive to a protein in a nut. Being exposed to the nut causes an allergic reaction.

Nut allergies are becoming more common in Australia and can be extremely serious.

About 1 in 5 children with a nut allergy will need emergency medical attention at some point. Extremely sensitive people can own a reaction if they are exposed to tiny traces of nuts; for example, through eating, breathing or simply touching a nut.

About 3 in 100 children under 12 months of age own a nut allergy. Some of them will grow out of it, but in about 1 in 20, the allergy will get worse. Nut allergies can also develop for the first time in adulthood.

People can be allergic to diverse types of nuts. The most common ones are peanuts, almonds, Brazil nuts, cashews, hazelnuts, macadamia nuts, pecans, pistachios and walnuts.

More information

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Australasian Society of Clinical Immunology and Allergy(Peanut tree nut and seed allergy), Journal of Allergy and Clinical Immunology(Prevalence of challenge-proven IgE-mediated food allergy), Sydney Local Health District(Peanut allergy)

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Last reviewed: July 2019

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Individuals with food allergy own an overreactive immune systemtowards aparticularfood.

Such a response happens due toan antibody calledIgE (Immunoglobulin E). Individuals suffering from food allergy often own a family history ofallergies.The most common food allergens are the proteins in cow’s milk, eggs, peanuts, wheat, soy, fish, shellfish and tree nuts.

The symptoms on food allergy may not depend on the quantity of allergenic food consumed and may even happen with consumption of tiny amounts. It is also significant to note that numerous allergens may cause symptoms even after they own been cooked, and even after undergoing the digestive process. On the other hand, some otherallergens, typically certain fruits and vegetables, may only cause allergies when consumed raw.

In some food groups, such as seafood andtree nuts, a phenomenon called cross-reactivity may be seen.

This implies that if an individual has an allergy to onemember of a food family, they may also beallergic to other members of the same food group.

What causes a tree nut allergy

Interestingly, cross-reactivitymay not be as commonly seen infoods from animal groups. For example, it has been found that individuals who may own allergiesto cow’s milk may still be capable toeat beef. Similarly, individuals with egg allergies may still be abletoeat chicken. It has also been found thatamong shellfish, crustaceans (shrimp, crab and lobster) are most likely to cause an allergic reaction.

What causes a tree nut allergy

Other mollusks such as clams, oysters and scallops are somewhat lesscommonly associated with allergies.

Symptoms of Food Allergies:
Symptoms of allergic reactions are commonly dermatological in nature and may causeskin itching, hives and swelling. Vomiting and diarrhea are common gastrointestinal symptoms. Symptoms of the respiratory system generally happen onlyin conjunction withskin and gastrointestinal symptoms.

Severe Allergic Reactions:
Anaphylaxis is a serious allergic reaction that happens extremely quickly and needs immediate and urgent attention!The symptoms often includedifficulty in breathing, loss of consciousness and dizziness.

If you noticeany of these symptoms,especially after eating, call 911 rightaway.

What causes a tree nut allergy

It is imperative to seek medical care immediately (call 911). Don’t wait to see if your symptoms go away or get better on their own. Without immediate treatment and effective and expert medical care, anaphylaxis can be lethal. It is essential to follow up with your allergist in such cases.

An allergist is the best qualified professional to diagnose food allergy. Your allergist will take a thorough medical history, followed by a physical examination. You may be asked about contents of the foods, the frequency, seasonality, severity and nature of your symptoms and the quantity of time between eating a food and any reaction.

Allergy skin tests may determine which foods, if any, trigger your allergic symptoms.

In skin testing, a little quantity of extract made from the food is placed on the back or arm. If a raised bump or little hive develops within 20 minutes, it indicates a possible allergy.

What causes a tree nut allergy

If it does not develop, the test is negative. It is unusual for someone with a negative skin test to own an IgE-mediated food allergy.

In certain cases, such as in patients with severe eczema, an allergy skin test cannot be done. Your doctor may recommend a blood test. Untrue positive results may happen with both skin and blood testing. Food challenges are often required to confirm the diagnosis. Food challenges are done by consuming the food in a medical setting to determine if that food causes a reaction.

Another question that is commonly asked is whether children outgrow their food allergies.

What causes a tree nut allergy

It has been reported that most children may outgrow  certain allergies such as those to soy, egg, cow’s milk, and wheat allergy, even if they own a history of a severe reaction. About 20% of children with peanut allergy will outgrow it. About 9% of children with tree nut allergy will outgrow it. Your allergist can assist you study when your kid might outgrow a food allergy.


The best way to treat food allergy is to avoid the foods that trigger your allergy. Always check the ingredients when eating, especially when out of home. Carefully read labels that indicate food information.

Carefully read food labels.

Always carry and know how to use injectable epinephrine and antihistamines to treat emergency reactions. Teach family members and other people shut to you how to use epinephrine! It is also significant to wear an ID bracelet that describes your allergy.

Food allergies can be confusing and isolating. For support, you may contact the Food Allergy & Anaphylaxis Network (FAAN) at (800) 929-4040.

(Information only; not intended to replace medical advice; adapted from AAAAI)

Tree nuts are a common food allergy: in the United States, about 0.5% of the population—or about one in every 200 people—is allergic to tree nuts. Tree nuts frequently cause strong allergic reactions and may cause anaphylaxis, which is a potentially life-threatening allergic reaction.

It's possible to be allergic to just one type of tree nut, but numerous people are allergic to multiple diverse types of tree nuts.

In addition, it's common for food manufacturers to process diverse types of tree nuts on the same equipment, raising risks for people who are allergic. Therefore, if you own a tree nut allergy, your doctor may warn you to avoid most or every tree nuts.

Symptoms of nut allergy

A mild reaction to nuts may cause the following symptoms:

Even if you generally only own a mild allergic reaction to nuts, you are still at risk of having an anaphylaxis.

Symptoms of anaphylaxis include:

Anaphylaxis is potentially life threatening and needs emergency medical treatment. You can read more about anaphylaxis on the ASCIA website.

Living with a nut allergy

If you are allergic to nuts, you must avoid any exposure to them, although it can be extremely hard to avoid every traces of nuts. ASCIA has a range of fact sheets with tips on avoiding diverse foods.

What causes a tree nut allergy

In particular:

  1. Take additional care when eating out. Asian restaurants can be particularly risky, although nuts are also often used in pesto, salad dressings and numerous other foods, too.
  2. Tell others about your allergy and what to do if you are exposed to a nut.
  3. Be careful when kissing or hugging someone who has eaten nuts (traces can stay on the hands, lips, teeth, beards and moustaches).
  4. Always carry your adrenaline autoinjector (EpiPen) with you.
  5. Always carry a supply of safe food with you when travelling.
  6. Take care with knives and forks, kitchen surfaces, barbecue plates, and shared butter and margarine that might be contaminated.
  7. Always read food labels.
  8. Be careful when eating other nut products — even if you don’t ponder you are allergic to them.

    You are at increased risk of developing an allergy to a new nut.

  9. If in doubt, don’t eat the food.

Children should take their own food to school and parties and should not share or swap food with other children. They may need to eat in a separate area from other children who are eating nuts.