Mustard is listed as a priority allergen in Canada. This page focuses on facts specific to mustard allergy, available resources, and special considerations related to this allergen, as well as possible cross-allergies and potential sources of contamination with mustard.

On this page:Statistics and facts on mustard allergy >
Mustard reference guide >
    Terms that may indicate the presence of mustard
    Foods that are likely sources of mustard
    Foods that are possible sources of mustard
Helpful resources >

Statistics and data about mustard allergy

  • There is limited research on the prevalence of mustard allergy, This allergy seems to affect children before the age of three[1].
  • Mustard seeds come from a plant of the Brassicaceae family, which also includes broccoli, cauliflower, cabbage, and Brussels sprouts.
  • Two main varieties of mustard seeds are used in cooking and manufacturing food: white seeds (yellow mustard) and brown seeds (Indian mustard). Black seeds (black mustard) are also available in the market [2].
  • The main allergens in mustard are Sin a 1 (yellow mustard) and Bra j 1 (Indian mustard). The two proteins have a similar structure [3]. Sin a 1 is resistant to heat and enzymatic degradation.
  • A study published in 2005 showed a correlated mustard allergy and sensitization to mugwort pollen (89%) and mites (68.4%)[4]. The researchers also found that all mustard-allergic participants were sensitized to other plants of the Brassicaceae family. Note that not all sensitized participants showed symptoms of an allergic reaction to the allergens of these plants. Further studies are needed to establish a possible cross-allergy between mustard and these plants.
  • Mustard contains irritant molecules (isothiocyanates and capsaicin) that make diagnosing an allergy to mustard difficult. These particles can cause non-immune reactions in some individuals similar to an IgE-mediated allergy. These reactions are believed to be responsible for some false positive results obtained in skin allergy tests to mustard [5]
  • Due to a high risk of cross contact, people allergic to mustard should avoid consuming commercial dry herbs and spices. It is best to choose fresh herbs, vegetables, garlic and onions as seasoning.
  • Some canola oils can be made from canola and mustard-canola-quality seeds. When highly refined, these oils contain negligible amounts of mustard protein and generally do not pose a risk. However, cold-pressed canola oils, which are less refined, may contain residual amounts of mustard protein. Health Canada, therefore, recommends that people with mustard allergies avoid consuming these cold-pressed oils [6]. As a matter of precaution, people with mustard allergy should consult an allergist before consuming canola oils.


Mustard REFERENCE GUIDE, PDF format (0,5 Mo) (in French)

Terms that may indicate the presence of mustard (non-exhaustive list)
Mustard seedsMustard oilPowdered mustard
Mustard as a condiment (old-fashioned mustard, Meaux, Dijon, strong, store-bought, etc.)All parts of the mustard plant (leaves, flowers, mustard shoots, etc.) 
Health Canada’s food allergen labelling regulations established in 2012 prohibit use of these terms. Manufacturers must declare the presence of mustard in the list of ingredients, either on the label of their product or in the words “Contains.” However, it is important to keep those terms in mind when travelling, as regulations vary from one country to another. In some cases, it may also be useful to know them when we are offered homemade or artisanal products.
Foods that are likely sources of mustard (non-exhaustive list)
Curry (carry or cari) and other Indian dishesSpice mixPickles and vegetable marinades
Food BreadingProcessed cheese (e. g. Cheez Whiz, Kraft Singles)Frying dough
MayonnaiseSauces (e.g. horseradish, barbecue, béarnaise, remoulade) 
Foods that are possible sources of mustard (non-exhaustive list)
Emulsifying agents and bindersRelishBroths and soups
SausagesDeli meatsFlavoring agents
Dried herbsAll products whose ingredient list contains spices or seasonings without further specificationKetchup
Dipping sauceCommercial ready-made meals (e.g. quiches and pizza)Dressings, including salad dressings
Possible sources of mustard in commonly used products (non-exhaustive list)
Pet FoodBeauty productsGlycerin
SoapsMilk substitutes for young animalsVitamins
Handmade products  
Note: To find out if commonly used products contain mustard, it is important to read the labels and contact the manufacturer. Food allergen labelling regulations apply only to packaged foods, they do not apply to non-food products.

Resources for people allergic to mustard

[1] Rancé, F., Dutau, G. et Abbal, M. (2000). Mustard allergy in children. Allergy, 55:496-500. DOI : 10.1034/j.1398-9995.2000.00383.x

[2] Santé Canada. (2009). Moutarde : un allergène prioritaire au Canada — un examen systématique. [PDF] Repéré à

[3] Rancé, F., Dutau, G. et Abbal, M. (2000). Mustard allergy in children. Allergy, 55:496-500. DOI : 10.1034/j.1398-9995.2000.00383.x

[4] Figueroa, J. et coll. (2005). Mustard allergy confirmed by double-blind placebo-controlled food challenges: clinical features and cross-reactivity with mugwort pollen and plant-derived foods. Allergy, 60:48-55. DOI 10.1111/j.1398-9995.2005.00644.x

[5] Rancé, F. (2003). Mustard allergy as a new food allergy. Allergy, 58:287-288. DOI 10.1034/j.1398-9995.2003.00109.x

[6] Santé Canada. (2016). Moutarde — Allergène alimentaire prioritaire. [PDF] Repéré à