CausesBy Mayo Clinic staff
An allergic reaction is somewhat like a case of mistaken identity by your body's immune system. Normally, your immune system generates antibodies to protect your body against bacteria, viruses or toxic substances.
If you have wheat allergy, your body creates an allergy-causing antibody to a protein found in wheat. In other words, your immune system mistakenly identifies this protein as something that could harm you. Once your body develops an allergy-causing antibody to a particular agent (allergen) — in this case, a wheat protein — your immune system is sensitive to it. When you eat wheat, your immune system mounts an attack.
There are four different classes of proteins in wheat that can cause allergies: albumin, globulin, gliadin and gluten. Any of them can cause an allergic reaction.
Sources of wheat proteins
Some sources of wheat proteins are obvious, such as bread, but all wheat proteins — and gluten in particular — may be used in a number of prepared foods and sometimes in cosmetics. Foods that may include wheat proteins include:
- Cakes and muffins
- Breakfast cereals
- Hydrolyzed vegetable protein
- Soy sauce
- Condiments, such as ketchup
- Meat products, such as hot dogs or cold cuts
- Dairy products, such as ice cream
- Natural flavorings
- Gelatinized starch
- Modified food starch
- Vegetable gum
- Jelly beans
- Hard candies
If you have a wheat allergy, you may also be allergic to other grains with similar proteins. These related grains include:
Wheat-dependent, exercise-induced anaphylaxis
Some people with a wheat allergy develop symptoms only if they exercise within a few hours after eating wheat. Changes in your body related to exercise either trigger an allergic reaction or worsen an immune system response to a wheat protein. This condition usually results in life-threatening anaphylaxis.
If you have exercise-related allergy to wheat, you may also experience an anaphylactic reaction when you eat or drink something with wheat and take aspirin or diclofenac (Cataflam, Voltaren) within a few hours.
The connection between these seemingly unrelated factors may be that exercise and aspirin use similar biological mechanisms to trigger an allergic reaction to wheat.
Baker's asthma is an allergic reaction to wheat flour and other types of flour. As the name of the disorder suggests, it's a particular problem for bakers or anyone who works with uncooked wheat flours. The allergic reaction is triggered by inhaling flour rather than eating it. Baker's asthma primarily results in problems breathing. But, people with Baker's asthma can usually eat cooked wheat products without having a reaction.
Celiac disease, or gluten-sensitive enteropathy, is considered a food sensitivity rather than a food allergy. Celiac disease is an abnormal immune system reaction to gluten that affects the small intestine. This condition can result in poor absorption of essential nutrients from your food. A person may have both wheat allergy and celiac disease.
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