What Causes Canker Sores? The exact cause of maximum canker sores is unknown. pressure or tissue damage is the idea to be the reason of simple canker sores. positive ingredients -- along with citrus or acidic end result and greens (consisting of lemons, oranges, pineapples, apples, figs, tomatoes, and strawberries) can trigger a canker sore or make the hassle worse. from time to time a sharp enamel floor or dental equipment, which include braces or ill-fitting dentures, may also trigger canker sores. A few cases of complex canker sores are caused by an underlying health situation, which includes an impaired immune system; dietary problems, consisting of diet B12, zinc, folic acid, or iron deficiency; or gastrointestinal tract disease, including celiac disease or Crohn's sickness. Mouth Sores & the Low-Acid End Result Mouth sores are extra not unusual than you may first think. approximately 20 percent of humans broaden canker sores on a normal foundation, in keep