Peanuts (also known as groundnuts) are legumes rather than tree nuts and grow underground.
There are 18 allergens recognised by the World Health Organisation (WHO) associated with peanut allergy.
These allergens include 2S, 7S and 11S seed storage proteins which are also found in many tree nuts.
Peanuts also contain plant profilin proteins, lipid transfer proteins and Bet v 1 proteins which are associated with Pollen Food Syndrome.
Peanut allergy is often linked to LTP Syndrome, where similarly shaped proteins in other plants resemble those in almonds and elicit an allergic reaction.
You may have Pollen-Food Allergy Syndrome if you suffer from peanut allergy with oral allergy symptoms to 3 or more of the foods mentioned in cross reactivity section.
Common foods involved in LTP allergy include kiwi, strawberries, sunflower seeds, walnut, apple, mulberry, banana, pea, apricot, cherry, plum, almond, peach pomegranate, raspberry, tomato, grape, celery, peanut, asparagus, cabbage, broccoli, chestnut, lemon, tangerine, orange, hazelnut, lettuce, lentils, lupin, green bean, pear, mustard, wheat and maize.
If sensitised to Birch pollen you may have Pollen Food Allergy Syndrome and may also react to Kiwi, Pear, Peach, Plum, Nectarine, Apricots, Cherries, Tomato, Celery, Carrot, Potato, Parsnip, Pepper, Dill, Cumin, Peas, Coriander, Fennel, Hazelnut, Walnut, Almonds, Apples, Lentils and Beans
Other food containing 2S albumin seed storage proteins are cashews, peanuts, almonds, mustard seed, rapeseed, turnip, chickpeas, hazelnuts, pistachio, buckwheat, soya beans, sunflower seeds, walnuts, kiwi, castor beans and sesame seeds.
Other foods containing vicilin like proteins not mentioned in the list above are lupin, lentils, macadamia, peas, pecans and mung bean.