TURNIP ALLERGY
Key Allergens
Turnips are in the Brassicaceae family of plants. Other plants in this food family includes rapeseed (canola), cabbage, papaya and mustard.
Turnips are usually small and white, larger ones which turn yellow are called swedes in the UK and rutabaga in the US. There are 3 food allergens associated with turnip allergy.
Bra r 1 is a 2S albumin protein. These are seed storage proteins most commonly found in nuts and seeds.
Bra r 2 is prohevein protein which is used in the plant for defence. Hevein proteins are linked to Latex Food Syndrome.
Bra r 3 is a polcalcin protein. These are panallergens, but are usually associated with airway allergies (plant pollens). In turnips this allergen is unique as it has been identified as a food allergen.
Turnips and swedes 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.
Turnips are usually small and white, larger ones which turn yellow are called swedes in the UK and rutabaga in the US. There are 3 food allergens associated with turnip allergy.
Bra r 1 is a 2S albumin protein. These are seed storage proteins most commonly found in nuts and seeds.
Bra r 2 is prohevein protein which is used in the plant for defence. Hevein proteins are linked to Latex Food Syndrome.
Bra r 3 is a polcalcin protein. These are panallergens, but are usually associated with airway allergies (plant pollens). In turnips this allergen is unique as it has been identified as a food allergen.
Turnips and swedes 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.
Food Intolerances
Turnips are a low FODMAP food. FODMAP stands for Fermentable oligosaccharides, disaccharides, monosaccharides and polyols. 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.
Turnips are low in salicylates. Salicylates have the potential to cause gastrointestinal food intolerance symptoms in people who are sensitive to salicylates.
You can read more about Food Intolerances on the dedicated Food Intolerance Page.
Associated Syndromes
Turnips contain prohevein which is similar in shape to those of latex plants, which can cause those suffering from Latex Food Syndrome to have allergic reactions to turnips.
Cross Reactivity
Other food containing 2S albumin seed storage proteins are cashews, peanuts, brazil nuts, mustard seed, rapeseed, pecans, chickpeas, hazelnuts, pistachio, buckwheat, soya, sunflower seeds, walnuts, kiwi, castor beans and sesame seeds.
Those with a sensitivity to hevein may have linked allergies to foods which contain high levels of chitinase, like banana, avocado, chestnuts, corn (maize), kiwi, papaya, pomegranate and tomatoes.
Other plants which contain polcalcin proteins as airway allergens are alder, ragweed, wormwood, birch, olive and lilac.
These allergen lists are not exhaustive. The Cross Reactivity Tool has the most up to date allergen information.
Those with a sensitivity to hevein may have linked allergies to foods which contain high levels of chitinase, like banana, avocado, chestnuts, corn (maize), kiwi, papaya, pomegranate and tomatoes.
Other plants which contain polcalcin proteins as airway allergens are alder, ragweed, wormwood, birch, olive and lilac.
These allergen lists are not exhaustive. The Cross Reactivity Tool has the most up to date allergen information.
Resources
Websites
Science Direct - Brassica rapa
Allergy information for: Turnip (Brassica rapa)
ATP Science - Salicylate Foods
Articles and Journals
Nutritional management of immediate hypersensitivity to legumes in vegetarians, 2022
A Comprehensive Review on Mustard-Induced Allergy and Implications for Human Health, 2017
2S Albumin Storage Proteins: What Makes them Food Allergens? 2008
Napins, 2S albumins, are major allergens in oilseed rape and turnip rape, 2006
Allergy to turnip greens, 2004
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