Canker sores are small, shallow, painful lesions that develop at the gum's base and on the mouth's soft tissues. Although their cause is unknown, canker sores may be triggered by problems with the immune system, hormonal changes, medications, trauma and food allergies. Speak with your physician if you believe your canker sores are symptoms of a food allergy.
Canker sore occurs in 20 to 60 percent of people, according to Collins Dentistry for Children. The condition -- one of the most common, non-traumatic ulcerations of the mouth -- typically appears on the tongue, soft palate, lips, inner surface of the cheeks and the base of the gums. The middle of the sore typically is white or yellow, and the perimeter is bright red. A few days before the sores appear, the person feels a burning or tingling sensation. While the cause of these non-cancerous sores is unknown, researchers believe a combination of factors including injury, food sensitivities, food allergy, auto-immune condition and hormonal changes contribute to an outbreak.
Food allergy is the result of an immune response against proteins present in the food. The immune system recognizes the protein as foreign and dangerous and mounts an Immunoglobulin E-mediated response against the allergen. IgE -- a class of antibody -- activates pro-inflammatory immune cells, mast cells and basophils that perpetuate the immune response by releasing histamine and other chemicals. These immune mediators trigger the symptoms of an allergic response including digestive problems, swelling of the mouth, lips and face, skin inflammation, hives, eczema, wheezing, nasal congestion and respiratory problems.
Food Allergy and Canker Sores
Milk, peanuts, tree nuts, wheat, soy, shellfish and fish account for 90 percent of all food-related allergic reactions, according to the Food Allergy and Anaphylaxis Network. An allergic reaction to foods including gluten, cow-milk proteins, chocolate, cinnamon, walnuts, tomato, figs, lemons and strawberries purportedly contributes to the appearance of canker sores. The release of histamine and other immune mediators in the mouth can result in cellular and tissue damage, and the appearance of canker sore as one of the symptoms of an allergic reaction. Since not all food allergy symptoms appear at once, try an elimination diet to determine whether your canker sores are related to a food allergy.
Treatment of Canker Sores
If you frequently develop canker sores, keep a food diary to help you identify the condition's trigger. Elimination of wheat and dairy products can help the sores resolve faster. In addition, avoid crunchy, spicy or irritating foods. Use soft toothbrushes and brush and flush your teeth regularly -- particularly after meals -- to avoid infection. Cleansing antiseptics like hydrogen peroxide diluted with water can help prevent an infection and promote healing. Over-the-counter medications such as Gly-Oxide and Zilactin can help alleviate the pain and discomfort.