Tree nut allergy: is it the same as peanut allergy?

Peanut allergy is among the most widely known food allergies. However, peanuts are not actually nuts. They are legumes, botanically closer to lentils and peas than to cashews or walnuts. This distinction matters clinically.

Tree nuts, including almonds, cashews, walnuts, hazelnuts, pecans and pistachios, come from trees and form a separate allergen group. Having a peanut allergy does not automatically mean you are allergic to tree nuts, though co-sensitisation is common and must be assessed individually.

Cross-reactivity between different tree nuts also varies. Someone with a cashew allergy may also react to pistachio (they are botanically related), but not necessarily to walnut or hazelnut.

Blanket avoidance of all nuts without testing can lead to unnecessary dietary restriction.

Component-resolved diagnostic testing can identify exactly which nut proteins you are sensitised to and help stratify your risk of a severe reaction giving you a much clearer picture than a simple positive result.