OBJECTIVE: Since the term orthorexia nervosa (ON) was coined from the Greek (ὀρθός, right and ὄρεξις, appetite) in 1997 to describe an obsession with \"correct\" eating, it has been used worldwide without a consistent definition. Although multiple authors have proposed diagnostic criteria, and many theoretical papers have been published, no consensus definition of ON exists, empirical primary evidence is limited, and ON is not a standardized diagnosis. These gaps prevent research to identify risk and protective factors, pathophysiology, functional consequences, and evidence-based therapeutic treatments. The aims of the current study are to categorize the common observations and presentations of ON pathology among experts in the eating disorder field, propose tentative diagnostic criteria, and consider which DSM chapter and category would be most appropriate for ON should it be included.
METHODS: 47 eating disorder researchers and multidisciplinary treatment specialists from 14 different countries across four continents completed a three-phase modified Delphi process, with 75% agreement determined as the threshold for a statement to be included in the final consensus document. In phase I, participants were asked via online survey to agree or disagree with 67 statements about ON in four categories: A-Definition, Clinical Aspects, Duration; B-Consequences; C-Onset; D-Exclusion Criteria, and comment on their rationale. Responses were used to modify the statements which were then provided to the same participants for phase II, a second round of feedback, again in online survey form. Responses to phase II were used to modify and improve the statements for phase III, in which statements that met the predetermined 75% of agreement threshold were provided for review and commentary by all participants.
RESULTS: 27 statements met or exceeded the consensus threshold and were compiled into proposed diagnostic criteria for ON.
CONCLUSIONS: This is the first time a standardized definition of ON has been developed from a worldwide, multidisciplinary cohort of experts. It represents a summary of observations, clinical expertise, and research findings from a wide base of knowledge. It may be used as a base for diagnosis, treatment protocols, and further research to answer the open questions that remain, particularly the functional consequences of ON and how it might be prevented or identified and intervened upon in its early stages. Although the participants encompass many countries and disciplines, further research will be needed to determine if these diagnostic criteria are applicable to the experience of ON in geographic areas not represented in the current expert panel.
METHODS: Level V: opinions of expert committees.

The present study reports a case series where three adolescent patients with anorexia nervosa (AN) (two cases with typical AN and one case atypical AN) received nasogastric tube feeding under restraint in line with new dietetic clinical guidelines.
Three cases were chosen out of 61 admitted patients over the period of 1 year who were fed via a nasogastric tube under restraint in a specialist eating disorders unit for children and adolescents. These cases were chosen to highlight a range of clinical scenarios that clinicians may encounter. They also represent clinical scenarios where decisions to feed patients under restraint were rendered more complex by additional concerns.
Despite the complexity of the cases, all patients tolerated the feeds well and were discharged home eating solid food.
The decision to feed a patient against their will is never an easy one. Sadly, there have been some recent high-profile deaths of adult patients on medical wards where treatment opinion was not considered, and the patient received no or minimal nutrition when awaiting specialist treatment. Dietetic guidelines have been published to help inform clinicians for whom feeding under restraint may be out of the scope of their daily practice. This case series highlights clinical scenarios that illustrate the utility of the guidelines, which we hope will support clinicians when making, potentially lifesaving decisions in children and young people.

Anorexia nervosa (AN) is a serious life-threatening illness that typically has its onset during the adolescent years. Evidence regarding the optimal treatment of AN in children and teenagers is growing; however, much remains unknown. Although current treatment approaches vary in Canada and elsewhere, the evidence to date indicates that family-based treatment (FBT) is the most effective treatment for children and teenagers with AN. A key component of the FBT model is that the parents are given the responsibility to return their child to physical health and ensure full weight restoration. An understanding of the basic principles and philosophy underlying FBT allows the physician to initiate elements of this evidence-based intervention to young patients with AN and their families.