Another reason we miss these diagnoses is that patients often do not fit the stereotypical phenotype of an eating disorder as eating disorders are seen in all genders, racial/ethnic identities, and socioeconomic backgrounds. Additionally, many patients with eating disorders have a normal body mass index (BMI) and may not appear underweight, especially male patients who may appear muscular due to excessive weightlifting (a common manifestation of anorexia nervosa in males). Finally, many patients with eating disorders have a lack of insight and/or denial, similar to patients with schizophrenia and dementia, and may deny feeling sick when they present to the ED with their parents.

It is important that we identify eating disorders in the ED, as the earlier treatment is started, the better the long-term outcomes (similar to schizophrenia), the lower the mortality rate, and the less likely they are to develop serious medical complications.⁴ With eating disorders missed often in the ED, and the importance of early recognition and treatment, there is an argument for universal screening at emergency triage with a quick screening tool such as the SCOFF questionnaire.⁹

The hallmark of anorexia nervosa is an inability or refusal to maintain a body weight at or above 85 percent of the expected weight based on age-appropriate BMI charts. Individuals with anorexia often engage in severe caloric restriction or excessive exercise as a means to cope with emotional distress or psychological pain, accompanied by an intense fear of gaining weight or becoming overweight. Bulimia is defined by episodes of uncontrollable binge eating, often followed by compensatory  purging behaviors such as self-induced vomiting or the misuse of laxatives. Individuals with the binge-eating/purging subtype of anorexia may also engage in similar binge and purge cycles. Those with bulimia can present at a normal weight, but they may also be underweight or overweight.

It is imperative that when assessing youth with vague physical symptoms or any psychiatric symptoms in the ED, physicians ask the patient and their parent(s) a few simple questions to screen for eating disorders: What is your highest ever weight and what is your weight currently? Do you make yourself sick because you feel uncomfortably full? Do you believe yourself to be fat when others say you are too thin? Tell me what you eat in a day. When was your last menstrual period?

If there is any suspicion for a possible eating disorder based on these questions, risk factors should be explored, investigations to screen for medical complications should be ordered, and specialist consultation or referral should be arranged. Risk factors for eating disorders include family history (as twin studies suggest that they are 60 percent to 70 percent heritable), personality type of high achieving perfectionism with a pronounced fear of failure, impulsive personality, participation in sports that rely on a lean and/or muscular body type, chronic medical conditions such as diabetes, and transgender youth.^10,11 It is a misconception that parents are the cause of eating disorders. Parental blame is counter-therapeutic and should be avoided.