Symptoms of itching or swelling in the lips, mouth or throat can occur within minutes of eating a food containing a protein similar to pollen.
These are some of the most common seasonal allergens and their cross-reactive foods:
Ragweed:
Bananas, melons (watermelon, cantaloupe, honeydew), zucchini, cucumber, dandelions, chamomile tea
Birch:
Apples, pears, peaches, apricots, cherries, plums, nectarines, kiwi, carrots, celery, potatoes, peppers, parsley, coriander, hazelnuts, almonds, walnuts
Grass:
Peaches, celery, melons, tomatoes, oranges
Source: The Children's Hospital of Philadelphia
related link: http://www.msnbc.msn.com/id/29036809/