Spice allergy can affect certain high risk populations including butchers, bakers, chefs, restaurant workers and even florists. Spice allergy generally affects young adults with birch tree or mugwort weed pollen allergy.
For the purpose of this blog, spices and herbs will be used interchangeably. Spices have been used for centuries for seasoning or flavoring food, but they can also be found in cosmetics, thus the higher prevalence in women. Spices can be utilized individually, but commonly are combined into commercial spice blends.
The common spices include: allspice, anise, basil, bay leaf, caraway seed, cardamom, cayenne pepper, celery seed, chervil, chicory, chili pepper, chives, cinnamon, clove, coriander, cumin, dill, fennel, fenugreek, garlic, ginger, horseradish, Jalapeno pepper, licorice, lovage, mace, marjoram, mint, mustard seed, nutmeg, onion, oregano, paprika, parsley, peppercorn (black, green, pin, white), poppy seed, rosemary, saffron, sage, savory, sesame, Star anise, tarragon, thyme, turmeric, vanilla and wasabi.
Biological effects of spices:
Apart from flavoring food, some hot spices (black pepper, paprika, cayenne, and chili) contain active and irritant substances that can affect the mucosa of the mouth or GI tract and potentially promote the transport of small molecules into the body. This may induce allergen sensitization. The hotter the spice, the more likely the effect on the cells in the GI tract. The substance capsaicin in particular has been shown to be pharmacologically active. The substance saponin can have detergent-like qualities which can affect the barrier wall of epithelium (lining of the GI tract).
Exposure to spices:
Not only do we eat spices, but spices can also be inhaled or have direct skin contact. Sporadic cases of allergic reactions to spices has been documented after ingestion. However, the main route of exposure for workers in the spice trade (farms, factories, groceries) is inhalation. Skin contact with spices occurs primarily in cosmetic handlers, food workers, butchers, chefs, home makers and occasionally in users of cosmetics.
Types of Reactions:
Non-immunologic (no specific effect on the immune system)
Irritant contact dermatitis (like dishpan hands) if handling. Sneezing, runny nose, eye itching, tearing and redness or cough can be from inhalation.
These can be similar to other food allergies and trigger hives (urticaria), swelling (angioedema), runny nose (rhinorrhea), red/itchy eyes (conjunctivitis), wheezing (like asthma) or even anaphylaxis. A person had night time tongue swelling from aniseed liqueur (smells like licorice). Another person inhaled spice powder containing curry, mace and coriander and suffered asthma symptoms.
Non-IgE Mediated immunologic reactions: T-cell mediated
This type of reaction is similar to that of poison ivy or nickel and occurs after skin contact with various spices including cinnamon or garlic. A curious reaction that occurs after sunlight exposure and skin contact with parsnip or parsley is called phototoxic dermatitis. The implicated ingredient is furocoumarins that on exposure to UV-A light induce a skin reaction with blistering (small or large) beginning 1-2 days after exposure and lasting several days. Interestingly some patients exhibit and eruption after ingestion of the spice in the same local area or even generalized (all over).
Main allergens in spices.
It has been determined that the main allergens are plant proteins including:
Plant defense system: these are pathogenesis-related proteins (PRP) and common in celery, coriander, cumin, fennel, parsley and anise. These proteins enable the plant to protect itself from microbes and other stresses. While it’s good for the plant, it is not good if you develop allergies to this diverse group of proteins.
Structural proteins: These are profilins and they are very similar amongst plants. There function is to mediate the communication between the cell membrane and the cell “skeleton” (cytoskeleton). These proteins are believed to be responsible for the cross reaction between pollens and food.
Prolamin: this group composes the protein albumin and LTP (lipid transfer proteins) This group is the most commonly implicated allergen in Rosaceae fruits especially in patients from the Mediterranean area without birch tree pollen allergy.
Cupin: This is a group of seed storage proteins that includes the 2S albumin in sesame seed and mustard and the 7S globulin called Vicilin in sesame and fenugreek.
Factor Affecting Spice Allergenicity
Spices can be used raw, fresh or dried. Similar to other foods, processing especially by heat (boiling, roasting, toasting, frying) may either reduce the allergenicity (allergic potential) by breaking down [denaturing] the protein or in some cases enhancing the allergenicity. Unfortunately, information on this for spices is very limited. Drying and grinding spices like paprika, chili or jalapeno pepper can destroy some of the profilins potentially making them less problematic. Most patients with celery allergy will react to both the fresh as well as the dried celery. Freeze-drying may enhance the allergenicity compared to whole spices.
Cross-Reactivity of Spices
There is a lack of information on cross-reactivity between spices. Even within botanical families, there may not be clinical cross-reactivity. Sesame and poppy seed have high cross reactivity. Also, a patient was described who had reactivity to both oregano and thyme (both in the Labiatae family). There may be partial cross reactivity between paprika and mace. Also, there may be cross reactions with onion and garlic. For most patients with spice allergy, there is pollen allergy, especially birch trees and mugwort weed. Except in occupational settings, nearly all spice allergy is related to birch tree pollen (Bet v 1 type allergen) allergy first. This has led to the descriptions of “celery-mugwort spice” syndrome and more recently the “celery-birch-mugwort spice” syndrome. This primarily affects young adults.
At Family Allergy Asthma & Sinus Care, we evaluate and provide management plans for all types of food allergy including spice allergy.