Eating certain foods can also produce a reaction if you have birch allergy. This is pollen food syndrome or oral allergy syndrome. It’s another type of cross-reactivity happens with other pollen allergies too.
Your body responds to certain fruit, vegetables, nuts or spices as if it was encountering the pollen. Birch cross-reacts with apples, apricots, cherries, peaches, pears, plums, kiwi, carrot, celery, parsley, peanut, soybean, almonds or hazelnuts. These foods contain similar allergenic proteins. Pollen food syndrome doesn’t cause hay fever. Instead you might get a mild, local reaction in your mouth and throat, lips and face.