Apart from the walnut family (walnuts, pecans) and the cashew family (cashew, pistachio and mango), every other nut species is unique and different, and there are at least eight families of plants that produce edible nuts. In spite of these chemical and structural differences, many people with nut allergy still seem sensitive to all types of nuts. The exact cause of this cross sensitivity is not understood, and one can only assume that plants producing nuts share in some common denominator, possibly producing and adding a chemical agent during the formation of nuts to prevent rotting.

(Remember that nuts are intended to be carried off and buried by animals.) It is therefore best to avoid all nuts once an allergic reaction has been experienced with any species of nut other that peanuts. (Peanuts are, strictly speaking, legumes, and although classified with other nuts are not true nuts.) Because of the difference between peanuts and other nuts, individuals with peanut allergy may attempt to experiment with other nuts, but we would advise you to proceed with caution.

The most common nuts implicated in allergic reactions are peanuts, walnuts and pecan nuts.

Peanut allergy can be dangerous and very severe, and will require strict surveillance. Many Chinese and Thai dishes, soups, marzipan and health foods contain peanuts or nut oils.