Eating Disorders - Dental Damage

Oral effects of eating disorders

For whom is this article intended?
What is an eating disorder?
Frequency of problematic eating behaviour among students
A student with an eating disorder on a dental visit: how do eating disorders come to light
Oral and dental changes in patients with eating disorders
What should be treated, teeth or disorders?
Oral observations of an eating disorder patient as a basis for self-care
Weight index for asessment of weight in proportion to height (kg/m2)
Predictive eating disorder steps before painful toothache develops



This guide has been written especially for you who are suffering from an eating disorder. If you feel that the text and instructions in this guide do not apply to you, you are wrong, in particular if you feel that they do not apply to you yet. We hope that you will read this guide from cover to cover even if the definitions might not at first seem to apply to you.

This guide has been made to help you. This guide contains information on eating disorders in general, and on the effects of eating disorders on the mouth and the teeth in particular. Some of the changes in the mouth are irreversible, and therefore their early treatment is important. This guide additionally contains practical instructions for dental self-care and for self-assessment of the damage, as well as general instructions for persons suffering from eating disorders. At the end of the guide there is a description of predictive eating disorder steps preceding painful toothache.

Eating disorders have increased in recent years, especially in young adults whose symptoms have continued for years. Most of the sufferers from eating disorders continue to be women, although the proportion of men is on an increase. The increase in eating disorders is mainly associated with cultural and societal factors: uncertainties in life, together with the requirements set by the fashion world on the figure of a woman, cause an increasing number of people to think excessively about their relationship with eating and dieting. Many young women have begun to believe that their value as human beings is determined on the basis of their looks.

This text has been checked, and improvements in it have been made, by Sirkku Heikkonen, M.D., as well as by a large number of students. We extend our warm thanks to all of them.  

What is an eating disorder?

Background of eating disorders
The thinking patterns and attitudes in the background of all eating disorders are to some extent the same, but for the sake of clarity the disorders are classified into anorexia, bulimia and atypical eating disorders. One and the same patient may, owing to the common background of the disorders, have features of more than one eating disorder. Sometimes bulimia may develop after anorexia.

Eating disorders usually emerge in adolescence or early adulthood, bulimia often later than anorexia. An eating disorder is the sum of many factors, and it may be triggered by a minor factor, such as thoughtless comments by close relatives or friends, or by a traumatic incident. Changes in a person’s life situation may also trigger an eating disorder. Such a change may be moving away from home, starting studies, breaking up an important relationship, or marriage. Eating becomes chaotic and/or uncontrolled.

In anorexia a person refuses to maintain her normal weight determined by body structure, height and age. An anorectic is afraid of gaining weight and considers herself or some part of her body too fat and ugly in spite of her underweight.

After drastic dieting at the early stage, the anorectic begins increasingly to hide her eating and not eating. She has divided foods into permitted and non-permitted, good and bad, and tries to follow this division in her eating.

An anorectic endeavours to exercise a great deal, and she may push herself to compulsive exercise and engage in exercise for hours each day. An anorectic’s life may also include bulimic symptoms: binge eating and vomiting, as well as the use of laxatives and diuretics.

Undernutrition and the reduction of fatty tissue to below normal lead to amenorrhoea and in the extreme case to childlessness. An anorectic’s skin dries, and delicate extra hair grows on her skin. An anorectic’s body temperature decreases, and so she feels cold all the time. Her vital functions and metabolism slow down, and consequently her health problems increase.

A person suffering from bulimia may gulp rapidly large amounts of high-energy foods. She feels that she has lost control of her eating, and to repair the situation after binge eating she vomits, uses diuretics or laxatives, exercises excessively, fasts, or starts a strict reducing diet.

Feelings of guilt and depression follow the feeling of loss of control of one’s life. A bulimic is ashamed of her excessive eating and purging. She hides her moments of binge eating from others and plans them for situations in which she can be alone.

Binge eating usually worsens when vomiting is linked with the disorder. Finally the eating pattern is completely disturbed: binge eating and restrictive dieting. The nutrition is often one-sided and does not contain sufficient vitamins, and so even a bulimic who is overweight may be undernourished with respect to the vitamin and trace element contents of her food. A metabolic state of undernutrition may incur when the body has to function on the terms of a fasting metabolism between meals.

A bulimic more often than an anorectic understands that she is in need of help, although feelings of shame may inhibit her from seeking help. Vomiting and the use of medicines are not very effective in preventing weight gain. The outer appearance of a bulimic may indeed be anything between underweight and overweight.

Many a bulimic is underweight with respect to her biologic normal weight, and thus cannot get rid of the consequences of starving or binge eating tendencies before she has reached her normal weight. The tendency to binge eat will level out when the bulimic has reached her normal weight and a normal rhythm of eating. The weight of some bulimics is close to the biologic normal weight, but owing to the chaotic eating habits their bodies react in the same way as those of persons who are underweight (basic metabolism slows down). Stomach problems are common in bulimics. Menstruation may become irregular or cease entirely. Misuse of laxatives may cause damage to nerves and muscles, in particular in the intestinal region. They cause disadvantageous changes in the liquid balance of the organism, thus making the bulimic person susceptible to severe cardiac arrhythmias.

Atypical eating disorders
The clinical picture of atypical eating disorders resembles anorexia or bulimia, but some essential symptom is lacking. This lacking symptom may be purging, or menstruation may continue in spite of a loss of weight. Binge eating disorder (BED) is the most common atypical eating disorder. A person suffering from BED may have binge eating attacks such as a bulimic has, but she does not purge herself. Instead, her binge eating ends in feelings of guilt, depression, or sleep. A person suffering from BED may also skip proper meals and replace them by snacking all day. BED often leads to severe obesity and extensive weight changes.

Predisposing factors
Eating disorders are associated with well-behaved and diligent nice girls who set high requirements on themselves. Perfectionism, low self-esteem and fear of failure are factors predisposing a person to eating disorders. Compulsive behavior and depression also do, but all of these factors may be consequences just as well causes of eating disorders.

Social uncertainty, lack of independence and a need to conform may also predispose a person to eating disorders. A job, hobby or illness in which weight restriction, looks, or dietary restrictions are of great importance also contribute to a predisposition to eating disorders. Dieting and the person’s own, or a family member’s, overweight increase the risk of contracting an eating disorder.

In the immediate circle of persons suffering from eating disorders, perfectionism, anxiety disorders, alcohol problems, depression and also eating disorders are more common than in the population on average. In spite of the common features and general conceptions, people contracting eating disorders differ widely from each other.

A strong fear of gaining weight and worry about weight are central in eating disorders. A person feels she is fat and begins to concentrate increasingly on her diet, exercise and looks. In the worst case her studies and/or work begin to suffer, because the monitoring of eating takes so much time.

Repeated or continuous dieting before long leads to mild undernutrition. It makes the person think about food continuously, and as eating controls her thinking, binge eating becomes more probable. Long intervals between meals and an irregular eating rhythm also lower the threshold to binge eat. Continual failure and a feeling of guilt, as well as chaotic eating, make the eating disorder a self-feeding vicious cycle.

Binge eating is triggered by various feelings that the person concerned is otherwise unable to cope with. These may include disappointments, failures, a feeling of helplessness, fear, anxiety, loneliness, and even boredom. These may be either subconscious or conscious.

It is easier for a person suffering from an eating disorder to fight against her own body than against the actual problem, i.e. insecurity with respect to her own feelings and sentiments. A person with an eating disorder feels that she is controlling the confused world when she is controlling herself and constricting her eating. The ill feeling is alleviated when the patient feels that she is in control. Respectively, a failure in controlling eating causes depression and feelings of inferiority.

A person with an eating disorder tends to react to things by changing her eating behavior. For example, a new environment may cause binge eating or a lack of appetite. Confusion in eating, together with undernutrition, causes depression and irritability. Mood changes and feelings of inferiority are emphasised. Starvation thus has a strong impact on mental functions.

Frequency of problematic eating behaviour among students

There are only a few male students suffering from eating disorders, whereas about every tenth female university student suffers from them. It is good to know that slight binge eating tendencies appear at times in a large proportion of all women. In 2001, there were about 130,000 university students within the scope of the services of the Finnish Student Health Service (FSHS); more than one-half of these students were women. About 35,000 female students felt they were too fat, and about 7,000 female students had eating disorders or had previously had eating disorders. Although almost one-half of the female university students assessed themselves as being overweight, only one-tenth was overweight in reality.

Binge eating may be associated with stress situations or with the premenstrual period, without being an illness. Irregular life and pressures regarding the progress of studies, livelihood and shifting to working life, as well as other changes in life coinciding within the same relatively short period of time, predispose a person to the emergence of eating disorders during the time of study. An eating disorder during the time of study may, however, often be mild and transient.

A student with an eating disorder on a dental visit: how do eating disorders come to light

Often patients with eating disorders are ashamed to tell the dentist about their disorders. In the background there may be shame about the disorder, as well as fear that the dentist will make the patient feel guilty and start preaching about treatment of the disorder. The central issue in dental care is the denture and the well-being of the mouth. The dentist may, when necessary, also refer the patient to care of the actual eating disorder if the patient is not yet otherwise receiving such care. FSHS provides help in eating disorders not only in dental care but also within health and sick care and in the mental health care unit.

However, some of those suffering from eating disorders talk about their problem or mention it on the preliminary information form. Usually patients who are already undergoing treatment for eating disorders, or have recovered, tell the dentist about it themselves, but those in the acute phase of the disorder often fail to do so.

From the viewpoint of dental damage and oral changes it is, however, important for the dentist to know their real cause. The symptoms are seen in different ways in the mouths of different people; in some they are visible earlier and more clearly than in others. There are not necessarily very clear changes specifically indicating an eating disorder, and in such a case the dentist cannot identify the eating disorder. Particular alertness is required of a dentist treating a patient with an incipient eating disorder, so that damage could be prevented in time. If you suspect that an eating disorder might have damaged your teeth or you are worried about the effect of the disorder on your mouth, do not hesitate to ask your dentist about it! A dentist knowing about your disorder will better be able to attend to the damage before it begins to cause pain and before it progresses to a severe stage, and can help you in treating the damage.

Oral and dental changes in patients with eating disorders

Eating disorders affect oral health in many ways. Some of the changes are irreversible, and untreated they will become worse. Irreversible changes include dissolving of the tooth enamel, an in some cases swelling of the parotid salivary glands. Even dental caries causes permanent damage in teeth. Fortunately, all of the changes are not irreversible; some are reversed as eating becomes normalised. Drying of the mouth, most problems in the gums, and mucous membrane problems caused by deficient nutrition, as well as early-stage swelling of the parotid gland can be repaired.

Erosion, i.e. dissolution of tooth enamel
The most common damage is erosion, i.e. dissolution of tooth enamel, caused by acid. Erosion causes lack of lustre of the teeth, initially only on the inner surfaces of the teeth. As erosion progresses, the upper teeth become smaller: the front teeth become shorter and often also narrower and thinner. The tips of the front teeth begin to look frayed. These thinned-out teeth break more easily and thus become even shorter. The papules of the molar teeth become rounded, and fillings in the teeth are left taller than the rest of the tooth. The damage is often more severe in the upper jaw than in the lower jaw, since acid remains on the nodular surface of the tongue longer than on smooth surfaces. As the tongue presses against the upper teeth, the action of acid also remains longer on them. A tooth may wear down even so much that the pulp of the tooth becomes bare. The shortening of the teeth leads to masticatory problems and subsequently to indefinite pains in the head and the face.

Changes of temperature, flows of air, touch, and certain foods cause dull pain or stabbing pain in the eroded teeth. In the sauna and at freezing temperatures it is painful to breathe through the mouth. Eating ice cream causes stabbing pain behind the front teeth. As erosion progresses, even wind or a light flow of air may cause a stabbing pain. Acid foods and drinks, which increase erosion, cause pain in the teeth already during eating. Touch may cause so much pain in the teeth that eating will be difficult. New enamel will not grow on the teeth to replace the dissolved enamel. Often the symptoms are alleviated, or they cease, when erosion is no longer active, i.e. its causes have been removed, in particular when the vomiting habit has ceased.

Erosive acid can come into the mouth from the stomach along with vomit or acid burps, or the acid may originate in food and drink. Foods that cause erosion include fermented foods such as sauerkraut, acidic fruits such as apples and oranges, juices prepared from them, vinegar, whey preparations, certain herbal teas (rosehip), soft drinks and sports drinks, and effervescent or chewing tablets of vitamin C. The sweetening of acid drinks increases their erosive action, since a sweet drink stimulates less the secretion of neutralising saliva. Brushing of the teeth immediately after the intake of acid food promotes the erosion of the enamel.

Drying of the mouth
Vomiting, fasting and undernutrition cause drying of the mouth. A decrease in saliva secretion increases the risk of damage caused by erosion, as saliva does not rinse the acid off as effectively as normally. As the rinsing effect of saliva decreases, more plaque accumulates on the teeth, and cavities form in them. The mucous membranes of the mouth tend to become irritated and infected more readily when they are dry. A dry mouth feels unpleasant, and the feeling of dryness may cause a person to wake up during the night to moisten the mouth. When the mouth is very dry, eating and even speaking become more difficult.

Caries, i.e. formation of cavities in the teeth
Persons suffering from eating disorders have somewhat more dental caries than do healthy persons on average. Caries progresses more easily and more rapidly in teeth on which the protecting enamel has thinned or entirely worn out. A person with an eating disorder may snack many times a day, in which case her teeth are subjected to too many acid attacks. Healthy teeth will well withstand a conventional number, i.e. 5 to 6, daily meals. The daily consumption of sugar may also be very large for persons with eating disorders. Owing to the drying of the mouth, the teeth cannot withstand acid attacks in a normal manner. A sufficient (normal) amount of saliva is the best protection against caries. Persons with eating disorders usually have cavities at the edges of the gums.

Problems and infections in the gums (gingivae) and mucous membranes
Problems in the gingivae and mucous membranes are caused by the dryness of the mouth and deficiency states due to deficient food. Dryness of the mouth causes accumulation of plaque, and therefore the gums tend to become infected and bleed. The mucous membranes are irritated by dryness. Iron deficiency may cause various inflammations in the mouth, the most common being infections of the tongue and the corners of the mouth. Both iron deficiency and vitamin B12 deficiency may cause at the corners of the mouth small ulcerations that become infected. Deficiencies of also other B vitamins may cause infections and changes in the mucous membranes of the mouth. Infections of the tongue and the corners of the mouth are often accompanied by fungal infections caused by yeast fungus. When necessary, the dentist will perform a fungus culture and prescribe medicines.

Swelling of the parotid gland
The parotid gland is located below the ear, next to the angle of the jaw and partly covered by it. It is the largest salivary gland, and therefore it is the site of the biggest salivary gland problems caused by an eating disorder. The swelling of the parotid gland is swelling with indefinite borders, and it makes the cheeks look thick and puffy. This swelling is always bilateral, and it is not associated with pain. Swelling of the parotid gland often appears in bulimics, since vomiting damages the gland, and this damage leads to swelling. Undernutrition may also be associated with the swelling of the gland. In general the swelling disappears when the vomiting habit ceases. If the situation continues for a long period, it will not necessarily return to normal, and cannot be corrected even surgically because of a risk of nerve damage. This typical change in the facial features will remain as a souvenir of an eating disorder.

What should be treated, teeth or disorders?

Oral problems due to an eating disorder are best treated by treating the eating disorder. However, dental damage at its worst is irreversible and may require the extraction of teeth, as well as extensive and expensive prosthetic measures. Therefore the prevention of damage at any stage of the disorder is worthwhile. Regular visits to the dentist are a cornerstone of this prevention.

Treatment of the teeth
Advanced erosion is treated by making prosthetic crowns on the teeth; in some cases plastic fillings may suffice. Sometimes root treatment may be necessary if the erosion extends to the pulp of the tooth. Milder erosion ceases to cause symptoms when exposure to acid ceases, and will thus not require corrective treatment.

The patient can inhibit the advancement of erosion by rinsing the mouth after vomiting or after the intake of acid food or drink with, for example, milk or water or neutralising stomach medicines, such as Samarin (a sugarless alternative is recommended). Brushing of the tongue with a toothbrush reduces the acidity of the tongue and prolonged action of the acid. Brushing of the teeth should be avoided for about an hour after the teeth have been exposed to acid.

Fluoride rinses and tablets reinforce the enamel and help it to withstand the action of acid. Fluoridised mouth rinses, chewing gum and lozenges are available without prescription at pharmacies. The use of fluoride and Xylitol chewing gums is beneficial for the teeth, because they also help to alleviate dryness of the mouth by increasing saliva secretion in addition to reinforcing and hardening the enamel.

Dentists do not have means to combat the swelling of the parotid glands or changes caused by nutrient deficiencies. Correction of nutrition and putting an end to the vomiting habit are the only treatments for these.

Treatment of eating disorders
The primary objective of the treatment is normalisation of the state of nutrition, i.e. raising or lowering the weight to the normal level by means of healthy and regular eating. Chaotic and uncontrolled eating habits must be given up. The treatment is carried out multiprofessionally, through the co-operation of a physician, a health nurse/nutrition therapist, a dentist and a psychologist/psychiatrist. Effective treatment is accomplished by combining behavioural therapy with nutritional counselling, and, when necessary, antidepressive drugs.

In practice, more than one half of patients with eating disorders in practice become completely healthy. About one third recover to some degree, but fall ill again later. In some the eating disorder becomes chronic with time. In some the eating disorder also leads to premature death.

Recovery from an eating disorder is possible, but it requires the patient’s own commitment to the treatment, recognition of her own condition, and a will to become healthy. Most commonly the patient’s attitude towards food will never return to completely normal; for example, the habit of reacting to situations with extra eating or with non-eating may remain. This means that one should not toy with one’s eating behaviour even after recovery.

It is often difficult for a person with an eating disorder to understand and express her emotions and physical feelings. During recovery, it is important to call attention to the understanding of these. Attitudinal changes are an essential part of recovery: a person’s value is not dependent on her looks, and the shape of her figure is not a selection criterion for anyone.

For whom is this article intended?

This article is intended primarily for students suffering from or suspecting eating disorders. At present, about 35,000 of the women studying at Finnish universities or other institutions of higher education feel that they are too fat, and about 7,000 women students suffer or have suffered from eating disorders. In our current culture there is thus a great deal of potential for continued increase of eating disorders and for contracting an eating disorder. An eating disorder often lasts for a long time, for months or years. During this time, changes of many kinds have time to occur in the mouth (as well as elsewhere in the body). Our purpose is to distribute information on these changes and on the possibilities for their prevention. The best prevention is to prevent the emergence of the disorder, and this is economically the most advantageous for all parties concerned, i.e. the patients, their immediate circle, and the entire health care system.

Oral observations of an eating disorder patient as a basis for self-care 

What is the problem?

What is the cause of the problem?

What can you do?

Stabbing pains in a tooth, for example in sauna, outdoors, in freezing weather or in strong wind, or when you eat something cold or acid

Chipping of the tips of your front teeth and their looking frayed.

Stomach acid brought into the mouth by vomiting and/or acid contained in acid food or drink has leached off enamel from the tooth. The tooth wears down, becomes smaller and weakens because of the wearing of the enamel.

After vomiting, rinse your mouth with, for example, milk or substances intended for neutralising stomach acids.

Reinforce your teeth with additional fluoride (tablets, a rinse) and use Xylitol chewing gum. Reduce the daily number of exposures of your teeth to acid attack. Do not brush your teeth for an hour after their exposure to acid.


Drying of the mouth, a need to moisten the mouth sometimes even during the night, the mucous membranes of the mouth may feel sensitive.

Vomiting, laxatives and diuretics, and deficient eating dehydrate the whole body.

Undernutrition and vomiting weaken the functioning of the salivary glands and may damage them, saliva secretion decreases.

Use Xylitol products (chewing gum, losenges).

When your mucous membranes are sensitive, you may rinse your mouth with lukewarm camomile tea or apply, for example, olive oil to the mucous membranes of your mouth.


More cavity formation in your teeth than previously.

The mouth may be dry, and saliva does not rinse the mouth sufficiently. Normal saliva secretion is the best protection for your teeth.

Under the effect of acids, the teeth may be more susceptible to forming cavities.

There may be too many times of eating, the consumption of sugar may be high.

Use fluoride tablets or a fluoride rinse in addition to toothpaste.

Favour Xylitol products.

Try to reduce the use of sugar and the number of times you eat. The recommended total number of times of eating is at maximum 5 – 6 times a day.


Your gums bleed in connection with toothbrushing.

Plaque has accumulates on the teeth and the gums, and plaque bacteria cause a gingival infection. More plaque accumulates when the mouth is dry or when the teeth are not brushed carefully and often enough.

Brush your teeth carefully twice a day.

Try combating the dryness of your mouth by using Xylitol chewing gum or lozenges.


Your cheeks at times look swollen and thick.

Vomiting and undernutrition have damaged the salivary glands so that they swell.

The swelling of the salivary glands is at first transient, and the situation returns to normal if the vomiting habit ceases.. Later the swelling may become permanent. There is no care for permanent swelling.

Weight index for assesment of weight in proportion to height (kg/m2)

You will get your own weight index by dividing your weight (kg) by your height squared (m2). Write down your weight and height precisely, using decimal points.


weight ( kg )


= --------------

height ( m2 )

Instruction for assessing your index number and weight 


severe underweight

BMI 15-17

medium-severe underweight

BMI 18-19

light underweight

BMI 20-25

normal weight

BMI 26-30

slight overweight

BMI 31-35

significant overweight

BMI 36-40

severe overweight

BMI >40

pathological overweight

Predictive eating disorder steps before painful toothache develops

  • You keep checking your appearance in the mirror and comparing it with your "imaginary ideal figure" continually, dozens of times a day
  • You are afraid of gaining weight even if you notice that you are already very thin.
  • Your ideal of thinness comes from today's fashion fad and is for you a measure of your value as a human being. Throughout your waking hours you constantly think of food and your eating. These compulsive thoughts will not loosen their grip on you even for a moment.
  • Your pursuit of exercise has gradually become an excessive everyday toil at the gym of on the jogging track, without a single day of fest or recuperation all week.
  • You demand of yourself perfection, and feel that you have failed if you do not always get the highest marks. You forget that second best marks are also achievements that could provide satisfaction in your life. Find yourself a hobby so that you will not think only about your marks.
  • Instead of having a balanced mind, good close relationships and feelings of success, you find satisfaction in your life, and you make yourself believe that you are in control of yourself.
  • Your experience has taught you that only trough vomiting you can find satisfaction in your life, and you make yourself believe that you are in control of yourself.
  • As your vomiting continues, you will after some time feel the first stabbing pains in your teeth. At their worst the stabbing pains will begin within a year, at the latest within a few years, depending on the severity of your eating disorder and the food you eat. Your teeth erode under the effect of stomach acids in the vomit and/or acid foods.
  • When the stabbing pains turn into nearly continuous feelings of pain, irreversible damage is developing in your mouth.
  • When you want to get your eating disorder under control and to balance your life, through your own efforts or by resorting to professional help, the changes eroding your health will cease, your system will return to normal, and even irreversible oral and dental changes can be managed. Do not prolong your disorder. Seek help and care courageously and without fear. Professionals will not interfere with your eating disorder by force or by moralising.


Article made by:
Lauri Turtola, docent, chief dental officer in FSHS
Ani Harva, ocont.lic.

Key words: Eating disorders