European scientists have discovered that despite popular belief, peanuts may not be the allergen that causes the most severe allergic reactions. In one important study, discussed at the the 2010 meeting of the American Academy of Allergy, Asthma & Immunology, that dubious distinction fell to the cashew.
The study, published in the European journal Allergy, found that in a group of 141 selected children with peanut or cashew allergy, the cashew group was more likely to experience shortness of breath, wheezing or cardiovascular symptoms during reaction than the peanut group. (This was despite the fact that a majority of the children with peanut allergy also had asthma.)
The Study and Findings
In 2007, researchers paired 47 children whose worst ever allergic reaction was to cashews with 94 children whose worst ever allergic reaction was to peanuts. Two children with peanut allergy were matched to every one child with cashew allergy and comparison criteria also included sex,
The study revealed that 22 per cent of children with cashew allergies experienced shortness of breath and/or collapse compared to 1 per cent of children with peanut allergies.
Also, while oral antihistamines were most frequently used as treatment by both groups, epinephrine was administered much more often in the children with cashew allergies. (Thirteen per cent of the cashew allergic compared to 1 per cent of the peanut allergic.)
What This Means
This study is important because: it shows the severity of tree nut allergies in general, the cashew specifically and raises the issue of the need for better public awareness.
The researchers advised fellow health-care professionals that “the diagnosis of cashew nut allergy increases the odds of a severe reaction and requiring intramuscular adrenaline and should also be considered in the risk assessment.”
As well in terms of managing the allergy, they noted that cashew can be a hidden food. “Cashew nuts present a considerable hazard, being hidden in a wide variety of commonly ingested foods, such as Asian meals, sweets, ice cream, cakes, chocolates and they are increasingly used in commercially prepared pesto sauce instead of pine nuts,” they wrote.
awareness in the public of the seriousness of tree nut allergy is not as high as awareness of peanut allergy. it places importance on tree nut allergies despite the fact that peanut allergies tend to get more attention in scientific studies and the media. While it is now very common to see “Peanut-Free” logos on snack foods and candy bars, it is rare to see the same for tree nuts.
Further, we now suggest that the diagnosis of cashew nut allergy increases the odds of a severe reaction and requiring intramuscular adrenaline and should also be considered in the risk assessment.
It has been suggested that cashew avoidance is easier than peanut avoidance (10, 14); nonetheless it is not straightforward. A recent study showed that 10/37 (27%) of nut-allergic children were unable to correctly identify the type of nut to which they were allergic (15). Cashew nuts are commonly sold as the whole nut alone, or packaged with other nut types. Cashew nuts present a considerable hazard, being hidden in a wide variety of commonly ingested foods, such as Asian meals, sweets, ice cream, cakes, chocolates and they are increasingly used in commercially prepared pesto sauce instead of pine nuts. Specific information on how to achieve nut avoidance should always be provided.
The study found that cashew allergies, specifically, are on the rise and are no longer uncommon. Furthermore, it can be just as challenging to avoid cashews as it is to avoid peanuts since cashews can hide in desserts, ice creams, trail mixes and other unexpected places.
More on this study, click here.