Food Allergies: The Top Ten Offenders

Allergies to wheat (gluten), mustard and sulfites, are less common than the last 7 allergies we described (Part 1, Part 2), though wheat is still one of the top 8 allergens that affect 90% of allergic individuals worldwide. Regardless of being less prevalent, these allergens are still ubiquitous in many of the foods we eat today. Not only are they a hazard to allergic individuals, these 3 ingredients have been linked to various diseases, sensitivities, and are often found in unlabelled foods such as produce.

References:
Food Allergy Research and Education
Health Canada
Current Allergy and Asthma Reports
Clinical and Experimental Gastroenterology
Nutrients
Allergy
Australasian Society of Clinical Immunology and Allergy

Gluten is the main structural protein complex of wheat and related grains such as barley and rye. A composite of gliadin and glutenin, hydrated gluten is responsible for the elastic properties of wheat doughs and contributes to the rise and chewiness of the final loaf. Gluten is also found in many non-bakery foods including pet foods and meat products, where it contributes to texture and protein content.

Gliadin, a component of the gluten protein, is responsible for the intestinal damage that Celiac patients suffer from. Gliadin causes this condition increasing the permeability of the intestinal lining. In turn, the inherent barrier function of the lining is disrupted, potentially allowing for the passage of environmental antigens involved in gluten-associated illnesses.

Gluten causes adverse (allergic, autoimmune and gastrointestinal) side-effects for those with Wheat Allergy, Celiac Disease and Non-Celiac Gluten Sensitivity. A recent paper published in Clinical and Experimental Gastroenterology found that gluten consumption is associated to Autism Spectrum Disorder. Likewise, another study published in Nutrients also linked gluten consumption to Type 1 Diabetes risk.

The second most heavily subsidized crop in the United States, wheat and its derived products are now present throughout the food system as well as being present in items such as chewing gum, cosmetics, textiles, and pharmaceutical tablets. This fact is concerning to those with gluten-associated conditions, such as those listed above. Due to the prevalence of these conditions, in August of 2013 the FDA instated a new regulation on gluten-free foods. This regulation required that any food labelled as gluten-free must have a maximum of 20 parts of gluten per million (ppm).

References:
Philosophical Transactions of the Royal Society B: Biological Sciences
Mayo Clinic
Clinical and Experimental Gastroenterology
Nutrients
Clinical Gastroenterology and Hepatology
Environmental Working Group
Celiac Disease Foundation
Food and Drug Administration
BMC Medicine

Mustard seeds are the small round seeds of mustard plants and are used in spice mixes, sauces, processed meats and Indian cuisine. Although mustard seed allergy is a fairly uncommon food allergy, it has been associated to conditions such as atopic dermatitis, and has cross-reactivity with mugwort pollen and the Brassica family of plants (cabbage, cauliflower, broccoli, Brussels sprouts, rapeseed, etc.). In addition, mustard seed allergy has been linked with sensitization to tree nuts, legumes, and the Rosaceae family of plants (apples, pears, peaches, strawberries, etc.), which can cause side effects in patients as severe as exercise-induced anaphylaxis. Also, since rapeseed and mustard seed are used in the production of Canola oil, it is suggested that those allergic to mustard seed be aware of this fact and consume canola products with caution. Canola oil is processed to remove mustard proteins, therefore it should not contain any allergens, but it may still pose a risk if improperly processed.

References:
Allergy
European Journal of Dermatology
Health Canada

Sulfites are a group of sulfur-based compounds that can occur naturally in foods, or can be added to food as a flavour enhancer or preservative. These compounds can be found in soup mixes, canned food, pickled vegetables, gravies, wine, beer and some medications. Sulfite sensitivity rarely results in anaphylactic shock, rather, it more often results in flushed skin, hives, wheezing, coughing, asthma, and chest tightness.

Some common misconceptions surrounding sulfites are that those who suffer with sulfite sensitivity cannot consume sulfonamide antibiotics, sulfur, or sulphates; the latter of which is found in many soaps and shampoos. Fortunately, these compounds are unrelated to sulfites, despite their names sounding similar. Though regrettably, sulfites can be found in foods where the ingredients are not listed such as on fruits and vegetables (to prevent browning) and on shellfish (to prevent melanosis). Therefore, in order to avoid sulfites it may be advisable to speak with your local fish salesperson to see whether sulfites are added to their shellfish, and to seek out produce companies that does not use sulfites.

References:
Web MD
Australasian Society of Clinical Immunology and Allergy
Health Canada