Millions of people in the United States, particularly teenage girls and young women, suffer from health-threatening eating disorders, and dentists are often the first to spot the signs. Why? The repeated, self-induced vomiting that characterizes bulimia nervosa has a pronounced effect on teeth. Anorexia nervosa (self-starvation) can also have some noticeable effects on oral health.

More than 90% of those with bulimia experience tooth erosion. This is caused by acid from the stomach, which can dissolve the enamel when it comes in contact with teeth during vomiting. Teeth that have lost enamel can appear worn, chip easily, and become sensitive to hot and/or cold. Of course, acid erosion can also affect people who drink a lot of soda, sports drinks and energy drinks — even the diet varieties. But acid erosion in bulimics has a particular pattern: It is evident on the upper front teeth, particularly on the tongue side and biting edges. The bottom teeth, on the other hand, tend to be protected by the tongue when a person throws up.

Once enamel is lost, it can’t grow back. But the damage can be repaired with various restorative techniques including veneers and/or crowns. The best treatment will be determined by how extensive the damage is, which in turn depends on how frequently the person has engaged in binge-purge behavior.

To protect teeth in the short term, it is important not to brush them immediately after vomiting as this can scrape off more of the softened enamel. It is better to rinse with water to which a little baking soda has been added, which neutralizes the acid. Even a plain water rinse is helpful. Sometimes a sodium fluoride mouthrinse is recommended to strengthen the enamel and reduce its loss.

Erosion is not the only sign of an eating disorder that a dentist or hygienist may notice. In severe cases the salivary glands can become enlarged, causing the sides of the face under the ears to look puffy. Also, the throat, back of the tongue and roof of the mouth can appear reddened or otherwise traumatized from the use of fingers or other objects to induce gagging. Soft tissues of the mouth can also be damaged by acid.

Only about 20% of anorexics experience tooth erosion, but there are other signs that may become apparent in the dental office. Nutrition and hygiene suffer in general, which in turn can mean more tooth decay and gum disease. There is also considerable overlap between anorexia and bulimia.

If you are struggling with an eating disorder or believe that a loved one is, please let your healthcare professionals know. We will make sure you get the help you need for healthy teeth and a healthy life. You can also visit the National Eating Disorders Association for some helpful information.