Tree Nuts and Allergies

Tree nuts such as almonds, Brazil nuts, cashews, chestnuts, hazelnuts, macadamias, pecans, pine nuts, pistachios and walnuts are full of beneficial substances for good health. Despite this, tree nut allergies are one of the most common food allergies in infants and children, and can persist into adulthood. If you have an allergy to tree nuts, it is crucial you know how to manage it correctly.

A food allergy occurs when the immune system reacts to a part of food. If you have an allergy to tree nuts, your reaction is likely to be severe and occur very soon after eating them. Food allergy is different to food intolerance. Food intolerance does not involve the immune system and reactions are often mild, occurring many hours after eating the food.

Food allergy affects between 5-8% of 0-5 year olds, most of who will grow out of it before they start school. Less than 1% of adults have food allergies. The most common food allergies in adults are to peanuts, nut and fish. There is currently no Australian data available on how many people have tree nut allergies but in New Zealand, they affect 0.6% of the population.

A skin prick test or Radioallergosorbent test conducted by an immunologist are the most reliable tools to diagnose tree nut allergies. If you suspect you have a tree nut allergy, ask your doctor for a referral to an immunologist.

Peanut allergies are different to tree nut allergies. Peanuts are legumes that grow underground. If you have a peanut allergy, you can still eat other nuts. One third of all peanut-allergic people are also allergic to tree nuts. In this case, all nuts should be avoided.

If you are allergic to tree nuts, you will need to avoid them completely. You will require a definite diagnosis and a planned approach that avoids the allergic food. Consultation with a specialist or accredited Practising Dietitian who specialises in food allergy is recommended. Reading ingredient labels for all foods and cosmetics is the key to maintaining control over an allergy. If unsure about the ingredients in a product, do not eat or use it until you have contacted the manufacturer.

In people with tree nut allergies, common reactions include:

• nasal congestion
• upset stomach
• hives
• cramps
• itching
• heartburn
• swelling
• gas
• wheezing
• diarrhoea
• shortness of breath
• light-headedness
• nausea
• fainting

Severe allergies can be fatal. Reactions usually appear immediately, although sometimes they can be delayed for a few hours.

In 2002 it became law to state the presence of commonly allergenic foods ( including nuts) on food labels. Always read labels closely. If you have a tree nut allergy, avoid products that contain the terms below in the ingredients list.

This list has been developed as a guide only. Other ingredients may contain, or have come into contact with, tree nuts. Always check with the manufacturer if you are unsure:

Almonds, loramine wax, palms, Amoretto, macadamia nuts, peanutamide, artificial nuts, mandelonas, pecans, bitter almond, marzipan, pesto, Brazil nuts, almond paste, pine nuts, caponata, mixed nuts nuts, pignolia, candle, nougat nuts, cashews, nut butters, pistachios, chestnuts, nut flavourings, pralines, frangelico, walnuts, gingko, gianduja, nutmeal, hazelnuts, nut paste, hickory nuts, nut pieces

An initiative of the Australian Nut Industry.

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