The following information is intended to help people with an allergy to cashews to manage their condition successfully. If you know or believe you are allergic to cashews, it is important to visit your GP and seek a referral to an allergy clinic.
Cashew nut allergens are highly potent, and for some people these reactions have the potential to be severe and even life-threatening (anaphylaxis).
The prevalence of cashew nut allergy is increasing, especially in children. Increased consumption of cashew nuts and a change in eating and cooking habits may be responsible.
Anyone who suspects they are allergic to cashew nuts should consult their GP and seek a referral to an allergy clinic.
How do I reduce risks?
When buying pre-packed food products, you should find cashew nuts straightforward to avoid so long as you read food labels carefully. Under European law cashew nuts must always be declared on the label. Foods where cashew is sometimes used as an ingredient include pesto sauce (which has traditionally been made from pine nuts) muesli and cakes.
Under EU law, food businesses selling catered or loose food are required to provide information to the customer about the presence of certain allergenic ingredients in their food. These ingredients include cashew nuts. You should question staff very directly, asking whether the nut you are allergic to is an ingredient of the food you have chosen. Don’t be afraid to ask the waiter to check with the chef. It is also important to ask about the risk of cross-contamination.
Cashews are used in cooking in the Far East and in the Indian sub-continent and may be found in ethnic food from those areas. We advise people with severe nut allergy to avoid Asian restaurants (such as Indian, Chinese or Thai) because nuts are so commonly used as ingredients, and there is also a risk of cross-contamination.
Cashews and pistachios can be used in baking, especially in Eastern pastries and in confectionary items, sweets, ice creams and chocolates.
Cashew nut butter is produced and is the equivalent of peanut butter. It is found in supermarkets as well as whole food shops.
Avoiding other nuts
The cashew nut and the pistachio nut are botanically related. Studies have found that people allergic to cashew are almost always allergic to pistachio as well. This is a process known as cross-reactivity — in which the proteins in one food are similar in structure to those in another food.
People allergic to cashew can also be allergic to other nuts. So is it best to avoid all nuts if you are allergic to one or two of them?
Some allergy experts would indeed advise that total avoidance is best in order to play safe. But others disagree. One review states: “In peanut or tree nut allergic children, introduction of specific nuts to which the child is not allergic may improve quality of life and should be considered in patients with multiple foods allergies, vegan or ethnic-specific diets, in whom nuts are an important source of protein.”
Our advice is that it depends what allergy tests you have had. If you have been tested for specific nuts, your doctor or allergist will be able to advise whether it is possible to include certain nuts in your diet. If you do eat specific nuts, it is usually advisable to do so at home so you can better control any risk of cross-contamination. Eating nuts from the shells can avoid the risk of cross-contamination from other types of nut.
If you have not been tested for specific nuts, then we believe in playing safe — avoiding all nuts — until you are able to be tested.
Oils and derivatives
Although it is technically possible to make a cashew nut oil from the nuts themselves none is commercially available for food use, as far as we know.
Derivatives of cashew are permitted in cosmetics and toiletries. Most commonly found in foundation make-up, shampoos, lotions and scalp creams. The terms to watch out for on the label are Anacardium occidentale extract and Anacardium occidentale nut oil.
You can see detailed information on anaphylaxis and its treatment on “Our Factsheets” webpage.
See the Factsheets on Adrenaline and Anaphylaxis the facts in the Anaphylaxis: general advice and information section.
This article has been reviewed by Dr Andy Clark, Consultant in Paediatric Allergy, Cambridge University Hospitals; and Dr Adam Fox, Consultant Children’s Allergist and Clinical Lead, Evelina London.
Disclosures: Dr Andy Clark has made no disclosure and Dr Adam Fox has no relevant disclosures.
All the information we produce is evidence based or follows expert opinion and is checked by our expert Clinical and research reviewers. If you wish to know the sources we used in producing any of our information products, please let us know, and we will gladly supply details.
Publication date: November 2015
Review date: November 2018