Eating Disorders and NIH Women's Health Research

Signs, Symptoms, and Risk Factors

Eating disorders are mental and physical illnesses that are characterized by severe disturbances in eating behaviors and distorted thoughts about food, body weight, and body shape. They encompass several conditions, including anorexia nervosa, bulimia nervosa, binge eating disorder, and avoidant/restrictive food intake disorder (ARFID), and they lead to significant functional impairment that substantially limits life activities.^{1 - 3} "Disordered eating" is used to describe eating patterns that vary in severity but do not meet the frequency, duration, and/or psychological criteria established by the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision for a diagnosable eating disorder.³

Anorexia nervosa, bulimia nervosa, and binge eating disorder have a lifetime prevalence of 0.28% to 0.85% in the United States.⁴ The prevalence of ARFID is less clear; worldwide estimates range from 4.51% to 11.14%.⁵ People with anorexia nervosa severely restrict their food intake, resulting in an abnormally low body weight, and they have an intense fear of gaining weight or becoming overweight and a distorted view of their own body size and shape.⁶ In another form of anorexia nervosa, called atypical anorexia nervosa, individuals meet all of the criteria for anorexia nervosa except that they do not have a very low body weight, despite significant weight loss.³

Bulimia nervosa is characterized by repeated episodes of binge eating while feeling a loss of control over eating. These episodes are followed by inappropriate compensatory behaviors, such as vomiting, laxative misuse, fasting, or excessive exercise.^{7 , 8} People with bulimia nervosa often have a body weight that is within or above the normal range. Individuals with binge eating disorder have frequent binge-eating episodes, but they do not engage in regular purging or other compensatory behaviors afterward.⁹ Binge eating disorder can occur across the weight spectrum, although individuals often have overweight or obesity.^{10 - 12} ARFID is characterized by avoiding eating or restricting food intake, often based on the sensory characteristics of the food, an anticipated negative response such as choking, or a lack of interest in eating.^{3 , 5} This condition results in significant weight loss or an inability to meet nutritional needs through oral food intake alone, but it does not involve concerns about weight gain or body shape.

Eating disorders can appear at any age, but they most commonly arise during adolescence and young adulthood, with a median age of onset between 16 and 21 years.⁴ The physical consequences of eating disorders can be profound, affecting multiple areas of the body, including the heart, kidneys, bones, teeth, and digestive system.^{1 , 10 , 11 , 13} For example, anorexia nervosa can cause low blood pressure, osteoporosis, kidney failure, and even death, and both anorexia and bulimia nervosa can lead to disturbances in electrolytes and reproductive hormones; menstrual irregularities, including amenorrhea; and pregnancy complications, including miscarriage, cesarean delivery, and preterm birth.^{10 , 11 , 13 - 15} Bulimia nervosa is associated with increased risk of cardiovascular disease and mortality.¹⁶

There is no single cause of eating disorders; instead, they arise from a complex interaction of genetic, biological, and psychological factors.¹ Social pressures, such as cultural emphasis on thinness, weight stigma, or exposure to unrealistic body standards, can also contribute to the onset of eating disorders, particularly among children, adolescents, and young adults.^{2 , 17} Athletes—particularly female athletes—such as gymnasts, long‑distance runners, wrestlers, ice skaters, and dancers are especially vulnerable to eating disorders due to the intense performance, aesthetic, and weight‑related pressures that are inherent to these disciplines.^{13 , 17 , 18} Eating disorders often co‑occur with other mental health disorders, including anxiety, depression, obsessive‑compulsive disorder, post-traumatic stress disorder, and substance use disorders.^{1 , 2 , 13 , 19 , 20} They are also associated with higher rates of suicide attempts.¹³

Impact on Women's Health

Although eating disorders can occur in anyone, girls and women are 12 times more likely to be diagnosed with anorexia nervosa during their lifetime than boys and men and 5.8 times more likely to be diagnosed with bulimia nervosa.⁴ They are also two to three times more likely to be diagnosed with binge eating disorder.^{4 , 21} Biological factors, including genetic, hormonal, and neurobiological influences, contribute to these differences in prevalence.²¹ The gender disparity is also influenced by societal and cultural pressures on women to achieve unrealistic body ideals—factors known to increase vulnerability to eating disorders.^{1 , 2 , 17 , 19} The reproductive health complications experienced by women with eating disorders compound the burden that these conditions already place on them.^{10 , 13}

Diagnosis and Treatment

The diagnosis of eating disorders typically involves a physical examination; a laboratory assessment, including complete blood count and comprehensive metabolic panel; a height and weight history; a mental health evaluation; and a review of eating-related behaviors, exercise patterns, and weight-control behaviors.^{1 , 10 , 13 , 18 , 20} Dental professionals may be the first to recognize the oral manifestations of eating disorders during routine examinations, particularly the effects of long‑term, self‑induced vomiting.²²

Effective treatment usually requires a multidisciplinary approach, including nutritional counseling; medical care and monitoring for complications; psychotherapy (e.g., cognitive behavioral therapy, family‑based treatment); and, when needed, medication.^{1 , 10 , 13 , 18 , 20 , 23} Supervised and structured meal programs, partial hospitalization, and residential treatment programs are also available for individuals who require a higher level of care.^{1 , 13 , 23} Although eating disorders can be successfully treated, especially with early identification and treatment, a meta-analysis of 415 studies found a pooled recovery rate of 46%, with recovery rates improving with longer follow-up periods.^{2 , 24}

Ongoing Research

Current research, led in part by the National Institute of Mental Health (NIMH) and the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), seeks to understand the genetic, biological, behavioral, psychological, and social factors that influence a person's susceptibility to developing and continuing to experience an eating disorder.^{2 , 8} In addition, there is increased interest in neuroscience-based research to advance our understanding of the neurobiological basis of eating disorders.^{25 , 26} Prevention efforts focus on using tailored dissonance-based approaches that are designed to challenge internalized appearance ideals, expanding the use of virtual interventions (e.g., videoconferencing), assessing the benefits and limitations of gender-diverse and gender-selective approaches to eating disorder prevention settings, and ensuring equity within prevention approaches.²⁷ Efforts to improve the early identification of patients with eating disorders are also needed, as is longitudinal research to clarify how depression, anxiety, psychosocial stress, and disordered coping mechanisms interact with eating behaviors.^{18 , 28} In addition, researchers are working to uncover links between eating‑disorder symptoms, gut health, and brain structure and function. Discoveries in these areas have the potential to advance the development of more targeted pharmacologic, behavioral, and psychosocial treatments, as well as technology‑supported treatments that promote patient engagement.^{2 , 28}

The NIMH Eating Disorders Research Program supports research on the causes, core features, progression, and assessment of eating disorders, including studies that identify genetic and environmental risk factors for their onset and recurrence. It also advances translational research that focuses on the development of new therapeutic interventions that are grounded in findings from psychopathology. As part of this effort, NIMH is supporting a study at the Icahn School of Medicine at Mount Sinai that aims to clarify how fluctuations in cognitive‑control processes across fasted and fed states contribute to binge, purge, and restriction cycles in women with bulimia nervosa. This study will generate insights to help inform more precisely targeted treatments for this disabling disorder.