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It's very common to get canker sores.

As many as 2 out of 3 people get bouts of recurrent canker sores at some time in their life.¹ You're more likely to get them when you are a young adult, but they're also common in children.² About 1 in 10 to 1 in 20 children have recurrent canker sores.¹

You may be more likely to get recurrent canker sores if:³

• You have too little iron, folic acid or vitamin B12 in your bloodstream
• You are sensitive to gluten, which is a protein found in wheat (this is called celiac disease)
• You injure your mouth (for example, by biting the inside of your cheek or grazing it with a sharp tooth)
• Someone else in your family has recurrent canker sores.

This information is for educational use only, and is not a substitute for prompt professional medical advice. Readers should always consult a physician or other professional for advice and treatment. ©BMJ Publishing Group Limited 2008. All rights reserved.