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Are Canker Sores an STD?

No, canker sores are not sexually transmitted. These small, round, painful ulcers inside the mouth might resemble cold sores caused by the herpes simplex virus, but they are not contagious.

Causes of Canker Sores

Canker sores can have many causes, but none of them are sexual. While the exact cause of canker sores is unclear, they’re most commonly associated with:

  • Allergies
  • Stress
  • Hormone fluctuations
  • Vitamin or mineral deficiencies
  • Mouth injuries
  • Illness
  • Dental work
  • Biting the inside of your cheek or your tongue
  • A genetic predisposition

Who’s at Risk

Women are more likely to get canker sores than men. They occur most often in young people in their teens and 20s; however, anyone can get them. You don’t have to be sexually active to develop canker sores. Because these sores often run in families, researchers believe they might have a genetic component.

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