Trying to hide an eating disorder will only go so far until your smile gives it away. Dentists are often the first medical professionals to spot signs of the disease, according to an article on eating disorders.
Your teeth are one of the parts of the body that take a hit when a person vomits on a consistent basis due to bulimia. When this happens, the enamel of the teeth wears away and your smile begins to discolor
If a person doesn’t receive the proper treatment or the disease continues, their teeth can actually fall out. These may be side effects that the sufferer of the eating disorder had never thought might happen
If the disease initially is caused by the person’s belief that their body does not fit into the "perfect" mold that is so often exemplified in the media, then they may not be focused on the other effects it may cause
Once they realize the rest of the breakdown of their body it may be too late, they are often already so taken by the disease, and it is hard to heal them on their own without medical attention.
These things are why it is so important for all medical professionals to be on guard when they see their patients. Those in healthcare should be able to know how to spot things that are not always obvious to the rest of the population. A person may just be seeking a routine teeth cleaning, but what can be learned from that appointment could end up saving her life.