Canker sores in the mouth are caused by a combination of factors, though the exact cause is not fully understood. Common triggers and causes include:
- Minor injuries to the mouth, such as from dental work, aggressive brushing, accidental cheek bites, or sports mishaps.
- Sensitivities or allergies to certain foods like chocolate, coffee, strawberries, eggs, nuts, cheese, and spicy or acidic foods.
- Nutritional deficiencies, particularly a lack of vitamin B-12, zinc, folate (folic acid), or iron.
- Emotional stress and anxiety.
- Hormonal changes, especially during menstruation.
- Use of toothpaste or mouth rinses containing sodium lauryl sulfate.
- Certain medical conditions such as celiac disease, inflammatory bowel diseases (like Crohn's disease), and immune system disorders.
- Genetic predisposition and a weakened immune system.
Canker sores are not caused by herpes virus and are not contagious. They usually heal on their own within one to two weeks but can be painful and irritating
. In summary, canker sores arise due to mouth injury, dietary factors, immune system issues, hormonal shifts, stress, and sometimes underlying health conditions.
