From the New Scientist magazine:
"Hazelnuts and apples are the most common triggers of food allergies in Europeans - not peanuts, as many might expect." Regional differences: "Peach and melon allergy is common in the Mediterranean - in Spain and Greece. Iceland is a hotspot for fish allergy."
Crossreaction between birch (Bet v 1), apple (Mal d 3) and peach ( Pru p 3) http://bit.ly/24Yh6G
Bet v 1 cross-reactions: people who have birch pollen allergy often react to apple, celery, plums and several other common foods.
Behind the names of food allergens: Pru p 3, a major peach allergen - from peach (Prunus persica) http://bit.ly/140g0j
Behind the names of food allergens: Mal d 3 (Lipid-transfer Protein) apple allergen - from apple (Malus domestica) http://bit.ly/Rh2mF
Behind the names of allergens: Bet v 1, the major birch pollen allergen - from birch, Betula verrucosa http://bit.ly/1nT0vT
Oral allergy syndrome (OAS, pollen-food allergy syndrome) is contact urticaria of the oropharynx. OAS is caused by allergens in fruits, vegetables, tree nuts, and peanuts that are homologous to pollen allergens.
What is oral allergy syndrome?
Unfolding of Pru p3 (peach) reduces resistance to GI proteolysis, almost completely abrogated IgE allergenic potency. JACI, 2011.
Image source: Silver Birch, Wikipedia, GNU Free Documentation License.