Oranges are in the Rutaceae
family of plants. Other plants in this family include grapefruit, lemon, lime, kumquat and sichuan pepper.
There are 4 allergens found in oranges.
Cit s 1 is a germin like protein (GLP). These proteins have a role in guarding against stress and pathogens in the plant.
Cit s 2 is a profilin protein
. Allergenic profilins are found exclusively in flowering plants and are minor pollen allergens.
Cit s 3 is a Lipid Transfer Protein
(LTP). These proteins are resistant to heat and are found in many types of plants. Patients suffering from a more severe allergy to cooked fruit may be sensitised to this group of proteins.
Cit s 7 is a gibberellin regulated protein
. Gibberellins are plant hormones associated with growth and development.
A 2023 study has shown oranges contain thaumatin like proteins
. These are proteins which give foods their sweet flavour. They are 'heat labile' proteins, which means they can cause allergic reactions after heating, cooking and processing.
Like other citrus fruits oranges contain furanocoumarins
. These chemicals can get on the skin and in combination with ultraviolet light (sunlight) can cause a sunburn like rash. Furanocoumarins are found in higher concentrations in fresh herbs and are natural irritants which can cause allergic contact dermatitis. This is more common in occupations where you are frequently coming into contact with the food, like chefs, cooks, growers and pickers.
Oranges are a low FODMAP food. FODMAP
stands for F
olyols. Foods high in FODMAPs can cause symptoms of food intolerance, affecting the gastro intestinal system and this can be mistaken for a true IgE food allergy.
Oranges are not high in histamine, but contain putrescine, which is another biogenic amine found in citrus fruits, chocolate, tea and nuts. Putrescine can have have similar effects on people who suffer with histamine intolerance. They have been flagged as amber here as it would depend on how sensitive you are as to how well you might tolerate them.
Oranges are a food high in salicylates
. Salicylates have the potential to cause worsening of asthma, swelling, itching and hives as well as food intolerance symptoms in people who are sensitive to salicylates.
You can read more about Food Intolerances
on the dedicated Food Intolerance Page.
You may be suffering from LTP Syndrome
if you have reactions to various fruits, vegetables and nuts and your reactions continue to be severe after you have discarded the peel and have cooked the food.
Allergy to orange is sometimes linked to Celery-Mugwort-Spice Syndrome
as the sensitising allergen is a profilin protein called Art v 4, these proteins are also sometimes also called Bet v 2 proteins.
There is also a link between orange and Latex Food Syndrome
. The plant involved in latex allergy Hevea brasiliensis
, the rubber tree plant, has an allergen called Hev b 8 which is a profilin protein. Those very sensitised to latex may have a contact allergic reaction from other foods or plants containing profilin proteins, there is less evidence of this than sensitisation to other latex linked proteins like hevein and chitinases.
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.
Other foods containing profilin allergens are celery, peanut, soyabeans, lychee, walnut, lupin, almonds, mustard, hazelnut, kiwi, pineapple, chilli, melon, strawberry, apple, banana, aubergine (eggplant), peach, pear, tomato, dates, cherry, carrot, barley and wheat. Allergic reactions to some of these foods may be considered a marker of profilin hypersensitivity.
Gibberellin regulated proteins are also found in chilli, cherry, apricots, peach and pomegranate.
Thaumatin proteins are found in apple, banana, cherry, pepper, garlic, grape, kiwi and peach.
Please note that these food lists are not exhaustive, the most up to date information can be found on the Cross Reactivity Tool.
Allergen Encyclopedia - Orange
DermNet NZ - Allergic Contact Dermatitis to Essential Oils
Lipid Transfer Proteins (LTP Syndrome)
Do You Have a Citrus Allergy? Learn the Symptoms
What are the symptoms of citrus allergy?
Histamine Intolerance Food List
ATP Science - Salicylate Food Lists
Articles and Journals
Food-dependent exercise-induced anaphylaxis to orange, with possible underlying thaumatin-like protein allergy, 2023
Capsicum Allergy: Involvement of Cap a 7, a New Clinically Relevant Gibberellin-Regulated Protein Cross-Reactive With Cry j 7, the Gibberellin-Regulated Protein From Japanese Cedar Pollen, 2022
Generalized allergic reaction in response to exercise due to strawberry gibberellin-regulated protein: a case report, 2022
Prevalence, clinical presentation, and associated atopic diseases of pediatric fruit and vegetable allergy: A population-based study, 2022
Allergy to Gibberellin-Regulated Proteins (Peamaclein) in Children, 2021
Gibberellin-regulated protein allergy: Clinical features and cross-reactivity, 2020
Lipid Transfer Protein allergy in the United Kingdom: Characterization and comparison with a matched Italian cohort, 2019
Identification of gibberellin‐regulated protein as a new allergen in orange allergy, 2018
Profilins: mimickers of allergy or relevant allergens?, 2011
Profilin sensitization detected in the office by skin prick test: a study of prevalence and clinical relevance of profilin as a plant food allergen, 2008
Germin‐like protein Cit s 1 and profilin Cit s 2 are major allergens in orange (Citrus sinensis) fruits, 2006
Isolation, cloning and allergenic reactivity of natural profilin Cit s 2, a major orange allergen, 2005
Lipid transfer proteins and allergy to oranges, 2005
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