This was previously called Oral Allergy Syndrome (OAS), the term was coined to define the symptoms. It has now been termed Pollen Food Allergy Syndrome (PFAS) more definitively as it mostly affects people who already suffer from pollen allergies and seasonal rhinitis due to cross reactivity.

In PFAS the body mistakes the shape of a protein that it is already sensitive to (a plant pollen) to a similarly shaped protein in certain fruits, vegetables, spices, herbs, and nuts.

The key allergen in PFAS is the pollen associated with the group of foods you are having symptoms from eating. It is most commonly associated with birch tree pollen, the allergen is called Bet v 1-like proteins.

If you are interested in which foods contain which allergenic proteins you can visit the Food Allergy Tool Page.

You may have Pollen-Food Allergy Syndrome if you suffer from oral allergy symptoms to 3 or more of the foods mentioned in cross reactivity section.

Celery-Mugwort-Spice Syndrome is a sub-category of Pollen Food Allergy Syndrome where profilin proteins are the sensitising proteins.

The main two cross reactive proteins associated with Pollen Food Allergy Syndrome are Profilin and Bet v 1. Below are screenshots from the Cross Reactivity Tool showing which foods contain which allergen.

Foods containing Bet v 1

Foods containing Profilins

You can read more about any of these foods from the dedicated Food Allergy Index or you can download a Bet v 1 and Pollen Food Allergy Syndrome Factsheet from the Allergy Resources Ko-fi Shop for just $0.90 (£0.69 or €0.82).

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