A question asked by many patients is, can you outgrow tree nut allergies? Tree nuts are common causes of food related allergic reactions and anaphylaxis. Resolution of tree nut allergy is thought to be now, yet studies are limited. In a previous blog post, we explored the rates of outgrowing peanut allergy.
We also explored seafood allergy. Can you outgrow seafood allergy?
A nut is a culinary term used to describe any large, oily kernels found within a shell and used in food. Common tree nuts include almond, Brazil nut, cashew, hazelnut, pecan, pistachio, and walnut. Tree nut allergies have emerged as one of the biggest clinical challenges in food allergy. Together with peanut, tree nuts are the most common trigger of adverse food reactions and fatalities.
Tree nut prevalence varies, it is been reported in studies that it can affect up to 5% of the population based on self reported data. Tree nut prevalence varies by regions. European studies report hazel nut as the most common tree nut allergy. Brazil nut is the most common tree nut allergy in the United Kingdom and cashew in Australia. Previous studies in the US had reported walnut and cashew as the most common tree nut allergies, however most recent survey data reports almond and cashew as the most common individual tree nut allergies in the United States.
Having both peanut and tree nut allergy has been based on self report between 20-60%, but based on actually studies and testing it may be closer to 4-40%.
Having an allergy to 1 tree nut will cause you to have a higher risk to another tree nut. Studies have shown the rate of a co-allergy between 40-100%. The most common tree nut co-allergies are between pistachio and cashew.
The resolution of tree nut allergy and predictors of persistence has been understudied. A recent study showed resolution of tree nut allergy to be 9%. Children with eczema and food allergies more were more likely to have persistent tree nut allergy. A self reported study from 40,000 households showed resolution at 14%, which was similar to peanut (16%) in this study.
More studies will need to be done to see the percentage of children who can outgrow tree nut allergies, but based on the above data, it seems pretty low with approximately only 10% of children outgrowing one of the tree nuts.