According to NHS Choices your genes may make you more likely to develop mouth ulcers due to certain triggers, as around %40 of people who have recurrent problems say they run in their family.
“The most common cause of ulcers is damage to the mouth, for example by accidentally biting the inside of your cheek or from a sharp tooth but certain foods are also a possible trigger,” says Kate Hoffmann, matron at Spire The Glen Hospital in Bristol.
Cheese, strawberries, coffee, chocolate, tomatoes, peanuts and wheat flour are all known culprits. Other possible triggers include hormonal changes, stress and simply feeling anxious.
"Mouthwashes help prevent bacterial infection and reduce swelling and some people find rinsing with warm salt water can also help. Using mouth gel straight from the fridge is also really soothing.”