Eating disorders are complex and serious illnesses that can result in physical and psychiatric comorbidities, medical emergencies and progressive health consequences. Although general psychiatrists may be called upon to assist in emergencies or differential diagnoses, training in this area has been limited. The author attempts to fill the gap by providing a summary of the most recent advances in the field of eating disorders in this chapter to help orient trainees and general psychiatrists. This chapter provides an overview of the most recent changes to the DSM-5 and ICD-11 diagnostic categories for eating disorders, as well as their epidemiology, aetiology and treatment, including the management of complications and life-threatening medical emergencies.

The chapter summarises recent advances in the genetic and neurobiological understanding of eating disorders, as well as emerging new research. These scientific advances have the potential to contribute to the development of new, more-effective eating disorder treatments in the future.

The primary empirically supported treatments for EDs are CBT-E and FBT. Both recommend a limited treatment team that includes a primary therapist who focuses on changing eating behaviors, weight, and related body image concerns; a medical provider to monitor stability; and a psychiatrist for medication management of any comorbid diagnoses. Dietitians may be used as consultants, and other types of therapy should be suspended during treatment. This approach aims to reduce the risk of conflicting messages among providers, treatment fatigue, and reinforcing of safety behaviors, but it has not yet become standard practice in ED treatment (particularly in the United States). Despite evidence supporting the efficacy of CBT-E and FBT, outdated ideas about ED maintenance and treatment persist in the healthcare community, which can be a challenge in treatment, especially when the patient also has a co-occurring diagnosis of OCD.

While there is a high rate of comorbidity between EDs and OCD, there is limited research on how to treat this comorbidity. Evidence-based treatments for EDs share many core tenets, though it is unclear which treatment features are necessary. CBT-E and FBT both focus on maintenance mechanisms, alliance building and providing a strong rationale for change. For underweight patients, they target weight gain and use in-session, collaborative weighing and weight graphs to document progress. Both focus on dietary restraint and restriction early on, and FBT indirectly and CBT-E directly target body checking, body avoidance, and social comparison behaviors. Both treatments prepare for relapse prevention and termination. There are similarities between the treatments for OCD and EDs, such as focusing on session agendas, providing structure and expectations for treatment, psychoeducation, a collaborative therapeutic relationship, and self-monitoring. CBT-E uses hierarchies and targets body checking and body avoidance similar to therapy for OCD. Both CBT-E and OCD treatments include elements of cognitive therapy, using corrective learning and behavioral experiments.

Dieticians play an important role in managing eating disorders – not just looking at nutrition but providing psychoeducation around nutrition, helping patients begin to normalise eating and making sure nutrition is adequate for growth, development and life-style. The reader is introduced to the depth and range of work that a dietician is able to provide.