The short explanation
Recurring mouth ulcers are common, and the idea that they come from a hot stomach is a popular belief rather than a proven cause. Most recurring ulcers are aphthous ulcers. Their exact cause is not fully known, but triggers include stress, minor injury from brushing or biting, certain foods, hormonal changes around periods, and sometimes low iron, vitamin B12 or folate. Most ulcers heal on their own within about a week or two. Avoiding spicy, sour and hard foods while they heal, using a soft toothbrush, and some pharmacy gels or rinses can ease the pain. If they keep coming back, a doctor can check for deficiencies or other conditions that can cause them.
What depends on your situation
The parts of this that change from woman to woman. Uncertainty is stated, not hidden.
- Ulcers that start around your period may be linked to hormonal changes.
- Frequent ulcers with diarrhoea, weight loss, joint pain, eye problems or genital ulcers need a doctor's check.
- An ulcer that lasts more than a few weeks, does not heal, or bleeds should be checked by a doctor or dentist.
- Tobacco and paan increase the risk of mouth problems, including mouth cancer.
What this answer cannot determine
The boundary of online education. These need a clinician who can see you.
- This cannot tell you the cause of your ulcers. A doctor or dentist may examine your mouth and order blood tests.
Questions for your clinician
Take these with you. You can add any of them to an appointment card.
- Could my ulcers be linked to low iron or B12?
- Are there any other conditions causing them?
- What can I use to ease the pain?
- When should I worry about an ulcer that does not heal?
When to seek help
Clinician-approved guidance for this topic. When in doubt, being seen is never the wrong choice.
Book an appointment soon
- See a doctor within a few days if ulcers are very painful, large, or you cannot eat or drink properly.
Raise it at a routine appointment
- Book a routine appointment if ulcers keep coming back, to check for deficiencies.
- See a doctor or dentist if any ulcer lasts more than a few weeks.
Sources
The evidence this explanation is built on.
- Mouth ulcers NHS
- Oral health World Health Organization
Who wrote and reviewed this
Every AskHer answer names its author. A clinically reviewed answer also names the clinician who signed it off — if no clinician is named below, it has not been clinically reviewed.
- Author
- AskHer Editorial (AI-assisted draft) AskHer's editorial team — not an individual clinician Works in English, தமிழ், हिन्दी
- Clinical reviewer
- Nobody yet No clinician has signed this answer off, and no person on the editorial team has read it yet. That is what the “Written with AI assistance” label means. It is queued for an editor to read, and then for a clinician who works in this area. The sources it was drafted against are listed above.
- Review status
- Written with AI assistance — not yet reviewed by a person
- Last reviewed
- Not yet reviewed by a person
- Version
- 1
Correction history
Substantive changes are listed, not quietly edited away.
No corrections have been made since this answer was first published.
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