Teeth can carry signs of an eating disorder well before anyone else has noticed. A 2023 systematic review in the Journal of Clinical Medicine (Nijakowski and colleagues) found tooth erosion in about 54 per cent of people with bulimia nervosa and about 27 per cent of people with anorexia nervosa. If you are living with an eating disorder, or worried about someone who is, dental care can protect the teeth while recovery happens, and it can be done privately and without judgement.
Acid is what wears the teeth
The damage is mostly chemical. When vomiting happens often, stomach acid repeatedly coats the teeth and softens the outer enamel, and over months that softened surface wears away. Diet can add to it, for example frequent acidic drinks, fruit or diet soft drinks, and so can a dry mouth, because saliva normally helps neutralise acid and repair early softening.
This is the same basic process as the dietary wear described in our guide to tooth enamel erosion, and similar to the wear seen with frequent reflux, covered in our article on acid reflux and the teeth. With vomiting, though, the exposure is often more frequent and the acid stronger.
The research reflects this. Nijakowski and colleagues found that people with bulimia were more than ten times as likely as healthy people to have erosion. An earlier meta-analysis in the British Journal of Psychiatry (Kisely and colleagues, 2015) found about five times the odds of erosion across eating disorders overall, with the highest odds in people who vomited and links with reduced saliva flow.
Where dentists see the changes
Erosion from vomiting usually appears first on the inside surfaces of the upper front teeth, the side facing the tongue, because that is where acid washes over most. The enamel there becomes thin and smooth, and the teeth can look glassy at the edges or chip easily. As the pale enamel thins, the more yellow layer underneath shows through. Older fillings may start to look raised, because the tooth around them has worn down while the filling has not.
Other signs can sit alongside erosion:
- teeth that feel sensitive to cold, sweet or acidic food
- a dry mouth, which raises the risk of decay
- painless swelling of the salivary glands in front of the ears and near the angle of the jaw
- cracked lips, a sore throat or mouth ulcers.
None of these on its own means someone has an eating disorder. Reflux, some medicines and diet can produce similar wear. A dentist looks at the whole picture and asks questions rather than jumping to conclusions.
Rinsing and brushing after vomiting
For years the standard advice was to wait before brushing after any acid exposure. More recent evidence has changed that. A 2024 scoping review in Caries Research (Fernández and colleagues) found that most studies showed brushing with a fluoride toothpaste did not increase erosive wear, whenever it was done, and concluded that brushing straight after an acid challenge can be recommended. There is no need to wait a fixed time.
Practical steps that may help protect the teeth:
- rinse with water after vomiting
- brush gently with a soft brush and fluoride toothpaste, without scrubbing
- use any higher-fluoride toothpaste or rinse your dentist or OHT recommends
- sip water through the day if your mouth feels dry.
What dental care can and cannot do
Dental treatment does not treat the eating disorder. That needs medical and psychological care, usually starting with a GP. What a dentist or OHT can do is slow further damage, ease sensitivity and keep the mouth comfortable, using fluoride, advice on dry mouth and regular reviews.
Enamel that has been lost does not grow back. Once vomiting has stopped and the wider health picture is stable, worn teeth can often be built up again with bonding, veneers or crowns, depending on how much tooth remains. Timing is important. Restorations placed while acid exposure is still frequent are more likely to wear, stain or fail, so rebuilding work is usually planned once recovery is well established, ideally in step with the person's medical team.
Privacy and pace
Many people avoid the dentist because they expect to be lectured or worry about what will be noticed. Kisely and colleagues pointed out that dentists may be the first clinicians to suspect an eating disorder, partly because people are often reluctant to seek psychiatric care. That makes the tone of a dental visit matter.
At Lumi Dental, your visit is confidential and the focus is on your health. You decide how much to share. We can care for your teeth whether or not you want to talk about the cause, and if you would like help finding support, we can point you towards it. If visiting the dentist itself makes you anxious, we offer a free consult for nervous patients, details of which are on our deals page.
Questions people ask
Will my dentist be able to tell?
A dentist may notice erosion on the inside of the upper front teeth or swollen salivary glands, which can be associated with eating disorders. These signs have other possible causes, so they are a reason for a private, careful conversation, not a diagnosis.
Can worn teeth be repaired?
Often, yes. Bonding, veneers or crowns can restore the shape and strength of worn teeth. The best results usually come once acid exposure has settled.
Should I brush straight after vomiting?
Current evidence suggests brushing gently with fluoride toothpaste does not add to wear, and rinsing with water first is reasonable. There is no set waiting time to follow.
Why does my face look fuller near my jaw?
Painless swelling of the parotid salivary glands is a recognised feature of some eating disorders. Mention it to your doctor and your dentist.
Support is available
If anything in this article feels familiar, talking to your GP is a good first step. The Butterfly Foundation, Australia's national charity for eating disorders and body image issues, runs a National Helpline on 1800 33 4673. For a confidential dental check-up, the team at Lumi Dental can help, and you can read more about our general dental care.
