Cross reactivity
Individuals who react to specific food allergens, inhalants or substances can develop an allergy to others. Such reactions may be to different foods containing the same allergen, or to an allergen with a very similar protein structure. Reactions can be either light or heavy and are known as allergic cross-reactivity.
This means that someone may suffer an allergic reaction even when avoiding the foods they know they are allergic to. If someone is allergic to peanuts, for example, they might react to soya, peas, lentils or beans – food items in the same biological family (legume).
Allergic cross-reactions can also happen between certain fruit or vegetables and latex (known as latex-food syndrome), or the pollens that cause hay fever.
If a person has a measurable reaction to a certain food with clinical diagnosis, avoiding similar foods that could trigger this reaction may be helpful.
The most well-documented cross-reactivity occurs between apple and birch pollen; however, individuals who are allergic to apple are not necessarily allergic to birch pollen. Cross-reactivity should not be assumed, and important foods should not be eliminated from the diet without appropriate testing and clinical diagnosis.
Clinical relevance
Light
Frequent occurrence
Mugwort
Possible occurence
Birch, weeping
Clinical relevance
Medium
Frequent occurrence
Birch, weeping
Possible occurence
Celery; Cherry; Cocksfoot; Mugwort; Peach; Pear; Potato; Ragweed, common; Rye-grass; Tomato
Clinical relevance
Medium
Frequent occurrence
Possible occurence
Almond; Apple; Celery; Cherry; Hazelnut; Parsley; Peach; Pear
Clinical relevance
Light
Frequent occurrence
Birch, weeping; Lilac, common; Olive
Possible occurence
Privet, common; Ragweed, common; Timothy
Clinical relevance
Medium
Frequent occurrence
Latex
Possible occurence
Banana; Kiwi
Clinical relevance
Heavy
Frequent occurrence
Latex
Possible occurence
Avocado; Birch, weeping; Goose-foot Kiwi; Melon
Clinical relevance
Light
Frequent occurrence
Blue grass, (Kentucky); Cocksfoot; Reed, common; Ryegrass, perennial; Timothy
Possible occurence
Celery; Olive; Rape, oilseed; Rye-grass; Sunflower, common
Clinical relevance
Medium
Frequent occurrence
Possible occurence
Almond; Apple; Apricot; Buckwheat; Carrot; Celery; Cherry; Coriander; Fennel; Hazel nut; Honey; Kiwi; Nectarine; Parsley; Parsnip; Pear; Peach; Peanut; Pepper; Plum; Potato; Prune; Spinach; Walnut; Wheat
Clinical relevance
Heavy
Frequent occurrence
Apple; Ash, common; Beech, common; Carrot; Celery; Chestnut, sweet; Cob, hazel; Curry; Hornbeam, common; Kiwi; Oak, English; Pear; Tomato
Possible occurence
Aniseed; Banana; Elm, Scottish; Caraway seed; Chamomile, German; Cherry; Coriander; Fennel seed; Hazelnut; Latex; Lychee; Mango; Mugwort; Olive; Orange; Paprika, condiment; Parsley; Peach; Pepper; Potato; Rape, oilseed; Rye-grass; Soy beanTimothy
Clinical relevance
Heavy
Frequent occurrence
Birch, weeping; Celery; Mugwort
Possible occurence
Cucumber; Head Lettuce; Mango; Melon
Clinical relevance
Light
Frequent occurrence
Possible occurence
Birch, weeping; Apple; Peach
Clinical relevance
Heavy
Frequent occurrence
Canary (serinus canarius); Chicken; Duck, domestic; Goose, domestic; Hen, domestic; Parrot, African gray (psittacus erithacus); Parakeet (nmphicus hollandicus) feathers; Parakeet (Melopsittacus undulatus); Pigeon
Possible occurence
Clinical relevance
Heavy
Frequent occurrence
Bermuda grass; Blue grass, (Kentucky); Melon; Oat flour; Rye flour; Ryegrass, perennial; Timothy; Vernal grass, scented
Possible occurence
Apple; Meadow, fescue; Oats, common; Reed, common; Rye-grass
Clinical relevance
Light
Frequent occurrence
Possible occurence
Carp; Eel; Herring; Mackerel; Plaice; Salmon; Sole; Tuna fish
Clinical relevance
Light
Frequent occurrence
Possible occurence
Barley; Blue grass, (Kentucky); Millet; Oats, common; Soy bean; Ryegrass, perennial; Rice; Wheat, common
Clinical relevance
Light
Frequent occurrence
Possible occurence
Oyster; Shrimp; Squid
Clinical relevance
Light
Frequent occurrence
Celery
Possible occurence
Carrot; Melon
Clinical relevance
Medium
Frequent occurrence
Birch, weeping; Celery; Mugwort
Possible occurence
Clinical relevance
Medium
Frequent occurrence
Latex
Possible occurence
Clinical relevance
Light
Frequent occurrence
Possible occurence
Birch, weeping; Celery Mugwort
Clinical relevance
Light
Frequent occurrence
Possible occurence
Peach
Clinical relevance
Medium
Frequent occurrence
Possible occurence
Melon; Orange; Swiss chard; Tomato; Watermelon; Wheat
Clinical relevance
Heavy
Frequent occurrence
Cob, hazel
Possible occurence
Birch, weeping; Kiwi; Mugwort; Peach; Poppy seed; Rue flour; Sesame
Clinical relevance
Medium
Frequent occurrence
Birch, weeping; Latex; Timothy
Possible occurence
Avocado; Banana; Hazelnut; Mugwort; Poppy Seed; Rye flour; Ryegrass, perennial; Sesame
Clinical relevance
Heavy
Frequent occurrence
Avocado; Banana; Edible Chestnut; Ficus benjamini (Tropic laurel, Weeping fig); Kiwi; Mango; Melon; Papaya; Tomato
Possible occurence
Apple; Birch, weeping; Buckwheat; Carrot; Celery; Dill; Fig; Mugwort; Orange; Oregano; Passion fruit; Peach; Peanut; Pear; Pineapple; Potato; Ragweed, common; Rye-grass; Sage; Soy bean; Strawberry; Timothy; Walnut
Clinical relevance
Light
Frequent occurrence
Possible occurence
Pea; Walnut
Clinical relevance
Light
Frequent occurrence
Possible occurence
Birch, weeping
Clinical relevance
Medium
Frequent occurrence
Celery; Cocksfoot; Latex; Ragweed, common
Possible occurence
Banana; Carrot; Cucumber; Goose-foot; Plantain, English; Zucchini
Clinical relevance
Medium
Frequent occurrence
Possible occurence
Carrot; Celery; Coriander; Fennel; Melon; Parsley; Pepper; Spices; Sunflower; Watermelon
Clinical relevance
Light
Frequent occurrence
Possible occurence
Asparagus; Garlic; Timothy
Clinical relevance
Heavy
Frequent occurrence
Possible occurence
Birch, weeping
Clinical relevance
Light
Frequent occurrence
Latex
Possible occurence
Clinical relevance
Light
Frequent occurrence
Possible occurence
Birch, weeping; Celery; Mugwort
Clinical relevance
Light
Frequent occurrence
Possible occurence
Lentil; Mugwort; Peanut
Clinical relevance
Heavy
Frequent occurrence
Tomato
Possible occurence
Latex; Lentil; Mugwort; Parietaria; Pea; Peach; Soy bean
Clinical relevance
Medium
Frequent occurrence
Possible occurence
Apple; Birch, weeping; Mugwort; Peach
Clinical relevance
Light
Frequent occurrence
Possible occurence
Celery; Birch, weeping; Mugwort
Clinical relevance
Light
Frequent occurrence
Possible occurence
Latex; Rye-grass
Clinical relevance
Light
Frequent occurrence
Possible occurence
Hazelnut; Kiwi; Rye flour
Clinical relevance
Medium
Frequent occurrence
Cat, domestic
Possible occurence
Clinical relevance
Light
Frequent occurrence
Possible occurence
Apple; Birch, weeping; Latex; Tomato
Clinical relevance
Medium
Frequent occurrence
Possible occurence
Apple; Banana; Cantaloupe; Chamomile tea; Honey; Honeydew; Nuts; Sunflower; Watermelon
Clinical relevance
Light
Frequent occurrence
Birch, weeping; Peanut; Rye-grass; Timothy
Possible occurence
Apple; Celery; Latex; Mugwort; Potato
Clinical relevance
Medium
Frequent occurrence
Possible occurence
Peach