Eating disorders such as anorexia nervosa, female athlete triad, bulimia nervosa, obesity, and binge eating initially emerge during adolescence. These disorders are present primarily in females, but males may also present with these conditions. Dentistry has a pivotal role in the management of patients with such diet-related disorders. Because dentists examine their patients at frequent intervals and may be the health care professionals with whom patients feel more comfortable discussing eating disorders, dentists must have knowledge of the etiology, diagnostic criteria, systemic effects, and intraoral manifestations of eating disorders. In addition, the dental professional may be the first health care provider to identify the condition and refer the patient appropriately to medical colleagues for subsequent treatment. This chapter provides dentists with current and relevant information to recognize, diagnose, and integrate dental treatment for their adolescent patients who may exhibit manifestations of an eating disorder.
The adolescent period is one in which individuals frequently engage in eating patterns that may negatively impact their overall well-being and dental health.
Dental practitioners have a responsibility to recognize their adolescent patients who fulfill specific criteria for various eating disorders.
Dental practitioners require foundational knowledge concerning the epidemiology and systemic effects of anorexia nervosa, female athlete triad, bulimia nervosa, obesity, and binge eating.
Dental practitioners should possess the discernment to refer patients with eating disorders to other appropriate medical, psychological, and nutritional specialists.
Dental practitioners must be proficient to assess intraoral manifestations of adolescent eating disorders and provide proper dental treatment or appropriate referral.
Proper diet and nutrition are key components that contribute to steady growth and development during the adolescent period. Unfortunately there are many adolescents and young adults who engage in eating behaviors that interfere with their overall health and well-being, including oral and dental health.
It is important at the outset to distinguish between 2 terms that relate to aberrant adolescent eating behaviors, namely, eating disorders and disordered eating. Disordered eating represents a range of multidimensional non-normative eating behaviors that may include practices such as fad diets, fasting, vomiting, misuse of diet pills, diuretics, or laxatives. In contrast, the term eating disorders represents patterns of malnutrition with inherent life-threatening potential that stem from underlying and complex psychiatric illnesses.
For this article, our scope will be confined to the categories of eating disorders as follows: (1) underweight and wasting patterns of malnutrition ( anorexia nervosa [AN], and the female athlete triad ); (2) underweight and/or normal weight patterns of malnutrition ( bulimia nervosa [BN]); (3) overweight patterns of malnutrition ( obesity , and binge eating ).
As of this writing, the world is in the midst of the COVID-19 pandemic. Dental professionals daily must confront the various aspects of this disease as well as ongoing updates regarding mitigation protocols. Although the long-term effects of the COVID-19 pandemic on adolescents with eating disorders and obesity have yet to be documented definitively, early research findings have been revealing. Where appropriate, these findings are included in the text.
Our intent for this article is to provide practicing dental professionals with current scientific evidence on adolescent eating disorders and obesity that may influence dentofacial development and intraoral conditions that require therapeutic dental interventions.
Underweight and wasting patterns of malnutrition
As we begin to explore the various patterns of eating disorders among adolescents, the term anorexia is likely to be among the most familiar. It is important to note, however, that anorexia is sometimes mistakenly used as a synonym for AN. Anorexia ( without appetite ) is defined simply as a loss of appetite or an inability to eat. Loss of appetite may be a secondary manifestation of other conditions such as depression, infection, cancer, or the side effects of medication, among others. From a dental perspective, for example, some adolescent patients may experience a temporary loss of appetite after extraction of third molars.
In contradistinction, the term Anorexia Nervosa ( nervous loss of appetite ) represents a complex psychological disorder with the potential to become life-threatening. This eating disorder consists of limiting food consumption to an extreme to maintain an abnormally low body weight, accompanied by cognitive distortions regarding body image. There are 2 clinical subtypes of AN , food restricting and food purging. It should be pointed out that terms used previously such as “self-inflicted” starvation or a “refusal” to maintain body weight implied a willfulness on the part of the patient. Current thinking now focuses more attention on behaviors such as “restricting calorie intake.” , ,
Epidemiology, prevalence, demographics
The onset of AN commonly occurs during the adolescent period with a peak range between 15 and 19 years of age. In the United States (US) and Europe, lifetime prevalence of AN is relatively low between 0.3% and 0.5%. While the prevalence for males and females may have increased somewhat over time, late adolescent and young adult females continue to account for 90% of reported cases. Although usually thought of as a disease primarily associated with white, middle-class females, there have been some increases in the frequency of AN noted in both minority populations and among those in lower socioeconomic strata. AN is associated often with various psychiatric comorbidities such as major depression, anxiety disorders, obsessive-compulsive disorder (OCD), as well as substance abuse.
Serious confounding factors of current relevance are health concerns surrounding the COVID-19 pandemic. As a novel coronavirus appeared then spread rapidly during 2020 resulting in the worldwide COVID-19 pandemic, concerns regarding the implications of this disease on global behaviors and health conditions expanded at a pace commensurate with the spread of the disease. While the total impact has yet to be determined fully, preliminary studies regarding the pandemic’s influence on the epidemiology, prevalence, and demographics of AN suggest an increase in both the number and severity of cases.
The criteria for a diagnosis of AN are established by the American Psychiatric Association; the most recent iteration being 2013. This revision (Diagnostic and Statistical Manual of Mental Disorders, fifth Edition [DSM-5]) contains some changes differing from those in the previous version (DSM-4).
To establish a diagnosis of AN , the patient must meet all the current criteria (DSM-5):
Restricted food intake with weight loss or a failure to gain weight. A “significantly low body weight” greater than what would be expected for peers of the same age, sex, and height.
Fear of gaining weight or becoming fat
Distorted self-image or an unrealistic view of their condition (denial)
There were 2 changes in the diagnostic criteria between the previous (DSM-4) and the current iterations (DSM-5) :
Amenorrhea was eliminated. The rationale behind this change was twofold: (1) It allows males to meet the criteria; (2) it allows females to meet the criteria who continue to menstruate despite extreme weight loss and malnutrition.
The low weight criterion was revised to allow more subjectivity and clinical judgment enabling professionals to integrate a patient’s unique growth trajectory and weight history into the overall assessment.
While it is not within the purview of the dental profession to diagnose or to treat the array of medical or psychological conditions that patients with AN may demonstrate, it is, nonetheless, essential for dentists to be sufficiently knowledgeable to recognize the signs and symptoms of this eating disorder and to initiate appropriate referrals as needed.
While some patients with AN may intentionally fail to report the existence of their eating disorder, others may even deny the existence of such a problem. Visual observation by the dental team can be invaluable in recognizing an adolescent with AN . The physical signs and symptoms that may be observable in the dental environment begin with the recognition that such patients are apt to appear along a range of body forms from slim to emaciated. Dehydration may be apparent, for example, the patient’s skin may appear dry or exhibit a yellowish cast. Fingernails may appear brittle, and nail beds may have a bluish discoloration. Fine lanugo body hair may be present, but scalp hair may be thinning, and some patients may admit to spontaneous hair loss. The eyes may appear sunken with dark shadows. Patients suffering from AN may complain of fatigue, insomnia, dizziness, fainting, or intolerance to cold. , ,
Serious systemic manifestations have been reported for individuals with AN. If malnutrition becomes chronic and severe, every organ has the potential to suffer damage to the extent that it may reach a level that is not fully reversible. Death becomes a possibility. , ,
Medical complications may include, but are not limited to, the following systems , , :
Cardiovascular: hypotension, syncope, bradycardia, mitral valve prolapse, heart failure
Gastrointestinal: bloating, constipation, nausea, vomiting
Hematopoietic: anemia, thrombocytopenia
Reproductive: females, absence of a period; males, decreased testosterone
Musculoskeletal: muscle loss, osteoporosis , elevated fracture risk
Metabolic: low blood levels of potassium, sodium, or chloride; metabolic alkalosis
In addition to the many physical signs and medical complications described, AN may be associated with a wide range of psychiatric comorbidities such as major depression, anxiety and other mood disorders, personality disorders, OCD, as well as alcohol and substance abuse. There may be an increased tendency for self-injury, suicidal thoughts, or suicide attempts. It is important to note that the mortality rate associated with AN is believed to be the highest among psychiatric illnesses. , , Research findings in behavioral genetics including family, twin, and molecular genetic studies suggest that substantial genetic influences might contribute to underlying causes of eating disorders.
Intraoral hard- and soft-tissue effects
Considering the multiplicity of factors that may coexist in patients with AN , it should not be surprising that these patients may exhibit a wide range of oral and dental conditions. The misuse of fad diets, diet pills, diuretics, or laxatives can have negative impact on the oral cavity in the form of xerostomia . Less than normal salivary flow interferes with the normal self-cleansing of the hard and soft tissues of the mouth. This dry type of environment fosters the development of dental caries.
Dehydration and xerostomia also may affect the soft tissues of the mouth. The lips may be dry and chapped; the corners of the mouth may develop angular cheilitis. Intraorally, the gingiva may look pale, or gingivitis with bleeding may be present. The palate may have the look of yellow-orange discoloration, and there may be signs of palatal petechiae. Atrophic mucosa may be observable. ,
Patients with the clinical subtype of chronic purging AN may exhibit swelling of the parotid glands ( sialadenosis ) and are at increased risk for the development of a specific type of enamel erosion of the lingual surfaces of the teeth ( perimylolysis ) , ( Fig. 1 ). As lingual erosion progresses over time from repeated episodes of acidic vomitus, chipping of the incisal edges of the anterior teeth begins to occur. That coupled with the occlusal erosion of the posterior teeth may lead to a loss in vertical dimension ( Fig. 2 ) and restorations that appear above the occlusal surfaces ( Fig. 3 ) which can contribute to the development of temporomandibular joint symptoms.
In addition to temporomandibular symptoms brought on by the loss of vertical dimension from perimylolysis , other psychiatric comorbidities such as major depression, anxiety disorders, or OCD may contribute to the clenching or grinding of teeth, placing added stresses on the joint and muscles. The symptoms of temporomandibular disorder may include dizziness, headaches, facial pain, and muscle fatigue.
For those individuals with AN whose condition progresses to chronic amenorrhea , osteopenia and premature osteoporosis may develop. This bone loss may be linked to a loss of alveolar bone.
Underweight and wasting patterns of malnutrition
Female Athlete Triad
The term female athlete triad was first introduced in 1992 by the American College of Sports Medicine. It was a term used to describe a clinical pattern observed among adolescent and young adult female athletes in sports such as gymnastics and figure skating, among others. Body image in these competitive sports contributes to the esthetic effect of the athletic performance. The same may be said for ballet dancers whose artistic performances are enhanced by their athleticism.
The female athlete triad shares characteristics similar to those found in nonathlete patients with AN ; namely a complex psychological eating disorder that limits food consumption to an extreme. That coupled with high-intensity athletic training regimens may result in amenorrhea and osteoporosis . , However, based on a revised position statement that was issued by the American College of Sports Medicine in 2007, the criteria for establishing a definitive diagnosis of the female athlete triad have been modified. ,
In this more recent iteration, the triad is currently characterized as a spectrum of interrelated conditions and complications. These include 3 components that were renamed: menstrual function , low energy availability with or without eating disorder, and low bone mineral density . According to this definition, athletes may present with any of the triad components, and they need not be present simultaneously for that individual athlete to suffer negative health consequences. , ,
Based on this latest clarification of the female athlete triad spectrum, the prevalence for patients demonstrating simultaneously all 3 of the components ranges from 1% to 2% among high school–aged girls and 0% to 16% for all female athletes. , Prevalence of 2 concurrent components ranges from 4% to 18%, and for a single component, 16% to 54% in high school–aged female athletes.
The systemic effects as well as the intraoral hard- and soft-tissue findings for the female athlete triad are essentially the same as those described in the section under AN.
Underweight and/or normal weight patterns of malnutrition
Another potentially life-threatening eating disorder named bulimia nervosa became recognized in the 1970s and was later identified as a specific disorder in the 1980s to establish the distinction between symptoms of bulimia ( binge eating ) and the binge eating/purge syndrome. Patients with BN , particularly the purging type, share similar signs and symptoms as those with AN . The essential difference between these 2 eating disorders relates to body weight of the individual. Those with BN may be of normal or above-normal weight, whereas individuals with AN continue to exhibit significant weight loss.
The binge-purge cycle involves eating large amounts of food followed by self-induced vomiting as one means of compensating for overindulgence. While patients with AN continue to severely lose weight over time, the physical effects of BN are manifested more in esophageal deterioration, menstrual irregularities, dental caries, perimylolysis, and vitamin deficiencies.
Epidemiology, prevalence, demographics
BN commonly begins in adolescence or early adulthood; onset before puberty or after the age of 40 years is uncommon. Frequently, the binge eating begins during or shortly after an episode of dieting to lose weight; for others, the onset of BN may be precipitated by a stressful life event.
In the US, the lifetime prevalence of BN is 1.5% in females and 0.5% in males. The disorder occurs across gender, ethnicity, and socioeconomic strata with similar prevalence. BN peaks in late adolescence and early adulthood in females; however, less is known about the prevalence in males because it is far less common than in females, with an approximately 10:1 female-to-male ratio. BN occurs with similar frequencies in most industrialized countries, such as Canada, Australia, Japan, and many European countries.
Three essential features must be present for a diagnosis of BN :
Recurrent episodes of binge eating
Recurrent inappropriate compensatory behaviors to prevent weight gain, such as self-induced vomiting, misuse of laxatives or diuretics
The binge eating and inappropriate compensatory behavior both occur, on average, at least once a week for 3 months.
While the severity of AN is graded based on body mass index (BMI), the severity of BN is based on the number of purging episodes during a given week. Degrees of severity are defined as follows:
Mild, 1 to 3 episodes per week
Moderate, 4 to 7 episodes per week
Severe, 8 to 13 episodes per week
Extreme, 14 or more episodes per week
Individuals with BN usually are within normal weight or overweight ranges with BMIs of 18.5 to 30 in adults. For adolescents up to the age of 19 years, BMI is calculated as sex- and age-specific. The disorder may occur among obese individuals but is uncommon.
After binge eating, the most common compensatory method used among those with BN is self-induced vomiting. This technique along with the misuse of laxatives accounts for more than 90% of the purging behaviors in BN .
Medical conditions that are observed in BN primarily are associated with purging behaviors and may present themselves in a variety of ways including during physical examination and through abnormal laboratory test results.
One specific dermatologic indicator that may appear is callous formation on the dorsal aspect of the finger or fingers used to self-induce vomiting. This finding is referred to Russell’s sign and is the result of repetitive trauma and skin abrasions over time attempting to induce emesis.
Self-induced vomiting also may result in subconjunctival hemorrhage and recurrent bouts of epistaxis. Red patches in the white portions of the eyes may appear disfiguring but are benign. They may be observed by the dental professional during a recall examination and should prompt inquiry about how it may have occurred. Frequent nose bleeds also should prompt further questioning.
Patients who self-induce vomiting often will complain of symptoms similar to those reported with gastroesophageal reflux disease. With repetitive vomiting, the esophageal musculature and epithelium are exposed to excessive acidic gastric contents and microtrauma. Consequences that may develop include esophagitis, esophageal erosions and ulcers, Barrett’s esophagus, and bleeding.
Abnormalities in electrolyte test results may indicate such conditions as metabolic alkalosis and hypokalemia from repetitive purging. Ultimately, this may lead to dehydration. Patients with BN may complain of dizziness, excessive thirst, and syncope. Cardiovascular and renal failure may occur in severe cases.
Similar to AN , BN is associated with various medical sequelae that depend primarily on the mode and frequency of purging. Some of these complications may be very serious, causing long-term or permanent damage to the adolescent.
Oral health effects
While examining the oral cavity, the dental professional may be the first health care provider to notice the effects of long-term, self-induced vomiting. Several abnormalities in the oral cavity have been reported and include
Reduced salivary flow rate
The maxillary anterior teeth are affected most severely by repeated self-induced vomiting. Perimylolysis may appear as early as 6 months after the onset of purging. The severity of this type of erosion is determined by the duration and frequency of vomiting, types of food eaten, oral hygiene, and the baseline quality of the tooth structure. Although mandibular teeth may be affected, they are generally protected from gastric acid exposure by the tongue.
An increased rate of dental caries may occur as a consequence of bingeing on large amounts of carbohydrates, poor oral hygiene, and increased intake of carbonated beverages, as well as acid exposure from purging. Gingivitis and periodontal disease may result from repeated exposure to gastric acid. The gastric acid, in turn, may cause chronic gingival irritation and bleeding.
Sialadenosis, hypertrophy of the salivary glands, is a common occurrence, having been reported in 10% to 50% of patients with self-induced vomiting. It generally appears bilaterally and only is minimally tender. The parotid glands are the most commonly affected salivary glands and often give patients “chipmunk-type” facies. It generally occurs 3 to 4 days after self-induced vomiting and may result from elevated serum amylase levels.
Overweight patterns of malnutrition
Obesity is a major, chronic health concern both globally and in the US. It continues to be the most prevalent nutritional disorder among children and adolescents, placing them at potential risk for a lifetime of poor health. For the purposes of this article, we propose the notion of obesity as a continuum that may transcend childhood onto adolescence, young adulthood, and beyond. Unless the continuum is interrupted, the adverse effects continue to mount. For example, too little physical activity and too many calories from food and drinks are the main contributors to childhood obesity, but genetic and hormonal factors may play a role, as well. Childhood obesity may lead to psychological problems such as poor self-esteem and depression. Adolescents who are obese may develop hypertension, hypercholesterolemia, impaired glucose tolerance, and other systemic disorders. So, suffice it to say obesity is a major public health concern and a multifactorial disease with physical, psychological, and social consequences throughout the lifespan.
Epidemiology, prevalence, and demographics
The prevalence of obesity among children and adolescents has almost tripled since 2000. Currently, obesity affects 19.3% of all children and adolescents (14.4 million) aged 2 through 19 years in the US. Americans, unfortunately, have one of the highest percentages of overweight adolescents among developed countries, and the probability of adolescent obesity persisting into adulthood is 80%. Over the past 30 years, the rate of childhood obesity has more than doubled, and the rate of adolescent obesity has quadrupled.
Although the demand for nutrients during adolescence is greater because of physical growth and pubertal development, this period is associated with an increased risk for the development of obesity, especially for female teens who have a larger deposition of fat than muscle. Boys and girls differ in body composition, hormones, patterns of weight gain, and susceptibility to various social, ethnic, genetic, and environmental factors.
Obesity for the childhood-adolescent continuum is defined as a BMI at or above the 95th percentile of the sex-specific BMI-for-age growth charts. In contrast, adult BMI does not depend on sex or age. The BMI is a noninvasive and indirect way of measuring body fat and is calculated by taking a person’s weight (pounds) and dividing it by their height (inches) squared. It is not a diagnostic tool, but rather an assessment to screen for potential weight-related issues. In addition, because BMI charts were developed from a nationally representative population, as Americans become heavier, the sensitivity of this measurement decreases. The American Academy of Pediatrics recommends using BMI as a screening tool for obesity in children starting at 2 years of age. Oral health care professionals have ideal opportunities to intervene during routine recall examinations by measuring the patient’s height and weight, followed by determining the patient’s BMI. In addition, taking the patient’s blood pressure may be an additional parameter related to obesity. If the BMI is in the overweight (85th to 95th percentile)/obese range and blood pressure in the hypertensive range, referral can be made to the patient’s physician for follow-up care.
The health consequences of obesity can present during the childhood-adolescent continuum, but the longer a person remains obese, the more that individual is at risk for health problems during adulthood. A high BMI during adolescence increases adult-onset diabetes and coronary artery diseases, threefold and fivefold, respectively. One of the most serious comorbidities of childhood obesity is type 2 diabetes. Other comorbid conditions which may manifest as a result of childhood obesity include, but are not limited to,
Abnormal lipid profiles
Nonalcoholic fatty live disease
Polycystic ovary syndrome
Obstructive sleep apnea
Bone and joint problems.
In addition, underlying psychiatric disorders, such as depression, poor self-esteem, anxiety, poor quality of life, and binge eating disorder, may cause or be a result of obesity.
Binge eating disorder
Binge eating disorder, which occurs in approximately 20% to 40% of obese adolescents and adults, is one of the most recent eating disorders recognized in the DSM-5. The disorder is characterized by recurrent episodes of eating large quantities of food, sometimes very quickly and to the point of becoming uncomfortable. In the binge eating disorder, the person does not use compensatory mechanisms such as purging to counteract the bingeing. The episode of binge eating must be characterized by both of the following:
Eating, in a discrete period of time, an amount of food that is larger than what most people would eat in a similar period under similar circumstances and
A sense of lack of control over eating during the episode.
Currently, it is the most common eating disorder in the US, three times more common than AN and BN combined.
Oral health effects
Research related to the association between obesity and oral health has been reported in the literature related to dental caries, dental development, periodontal diseases, and sedation. However, obesity is a multifactorial disease for which cause-and-effect relationships are difficult to establish definitively. Here, we focus on the following topics:
Similar to obesity, dental caries is a chronic, prevalent, multifactorial disease afflicting US children and adolescents. Dental caries and obesity both share one distinct contributing factor—diet; both of these conditions often are left untreated. In addition, dental caries is highly associated with lower socioeconomic status. Even though research on the association between obesity and dental caries has been conducted for many years, the results have been ambiguous.
In a recent systematic review of BMI and dental caries in subjects younger than 18 years, evidence of an association between BMI and caries was inconsistent. Of the 4208 identified studies, this review included 84 that met the inclusion criteria for determining potential associations between BMI and caries:
26 studies showed a positive relationship
19 showed a negative association
43 found no association between the variables.
Well-designed, longitudinal studies evaluating the association of various indicators of obesity and dental caries during childhood and adolescence may assist in elucidating this complex relationship.
The biological processes of dental and skeletal development have been used as stable benchmarks to determine physical maturation. Obese children have been shown to grow at an accelerated rate and reach skeletal maturity and puberty earlier, and increased BMI has been associated with accelerated growth, premature puberty, and early sexual development.
In numerous studies from various locations in the US, childhood obesity was found to be associated with accelerated dental development and eruption of permanent teeth, and patients with higher BMI values were more likely to have advanced dental development for their age at a significant level ( P <.001).
Other studies among various racial and ethnic groups (Hispanic, Asian, White, Black) demonstrated further that differences in dental age, when compared to chronologic age, were significantly greater in children who were overweight/obese versus their underweight/average counterparts. ,
As the prevalence of obesity increases in the US, dental professionals need a better understanding of how obesity with increased BMI affects dental development. Predicting the stage of dental development, eruption and sequence in the mixed dentition are critical for appropriately timing dental treatments for best outcomes such as space maintenance by the pediatric dentist. The timing of orthodontic intervention based on dental age rather than chronologic age should be essential to the orthodontist in obtaining not only radiographic records but also BMI values. These same factors are key in evaluating adolescent prosthodontic patients for placement of an esthetic anterior implant based on both the dental and skeletal ages of the individual. For oral and maxillofacial surgeons, the timing of third molar extractions may be earlier for their obese adolescent patients than for nonobese and underweight patients.
An association between obesity and periodontal disease was first reported in 1998 in Japan. Since then, a number of studies have identified obesity as a risk factor for the development of periodontal disease, and several cross-sectional studies have reported that obesity is associated with increased prevalence of chronic periodontitis in adults. ,
To better comprehend how obesity may contribute to periodontal disease, an understanding of how adipose tissue functions in the body is relevant. It is important to stress that adipose tissue is not merely a passive triglyceride reservoir of the body, but rather it generates vast amounts of cytokines and hormones, collectively called adipokines or adipocytokines. These substances are involved in inflammatory processes that point toward similar pathways associated with the pathophysiology of obesity, periodontitis, and other related inflammatory diseases. While the underlying biological mechanisms linking obesity with periodontitis are not fully understood, adipokines or adipocytokines may play a key role.
Associations between obesity and periodontal risk indicators in obese adolescents have been reported. Given the generally high prevalence of obesity among adolescents globally, it seems prudent to investigate early markers of periodontal disease to better manage them. In a Belgian study of obese adolescents, the obese group showed higher incidence of caries, gingivitis, and plaque, although after adjusting for age and sex, obesity was associated significantly only with the presence of dental plaque ( P ≤.001). The obese participants reported a significantly elevated intake of sugar-rich and high caloric food than the normal weight group, a factor that may be contributory to the presence of dental plaque ( Fig. 4 ).