Vol.:(0123456789) 1 3 Eating and Weight Disorders - Studies on Anorexia, Bulimia and Obesity https://doi.org/10.1007/s40519-020-00909-4 ORIGINAL ARTICLE Optimizing the empirical assessment of orthorexia nervosa through EHQ and clarifying its relationship with BMI Valérie Godefroy 1  · Laura Trinchera 2  · Géraldine Dorard 3 Received: 17 October 2019 / Accepted: 17 April 2020 © Springer Nature Switzerland AG 2020 Abstract Purpose Orthorexia nervosa (ON) is described as an obsession for healthy eating with potentially debilitating consequences but little of its psychopathology is empirically supported. Using suitable validation methodologies, we wanted to optimize the empirical assessment of ON symptoms and investigate their unclear relationship with BMI. Our objective was, therefore, twofold: (1) Validation of a robust measurement model of ON dimensions using the Eating Habits Questionnaire (EHQ); (2) Validation of a structural model describing a mechanism of relationships between ON dimensions and BMI. Methods A self-report questionnaire assessing BMI and ON through a French translation of the 21-item EHQ was admin- istered to a large sample of French adults (N = 2065). We used Exploratory and Confrmatory Factor Analysis for objective no. 1 and Structural Equation Modeling for objective no. 2. Results We validated a well-ftted (TLI = 0.98; RMSEA = 0.04) and conceptually consistent measurement model with 16 items for three ON dimensions: Rigid Eating Behavior (REB), Positive Feeling of Control (PFC) and Problems of Attention Control and Social Relationships (PACSR). We also validated a structural model (TLI = 0.96; RMSEA = 0.05) showing that: 1. REB strongly impacts both PFC and PACSR; 2. REB has a signifcant negative impact on BMI and BMI has a signifcant positive efect on PACSR but efect sizes are very small and globally ON dimensions are only marginally related to BMI. Conclusion Our study achieved an improved assessment method of ON, a clarifcation of its links with BMI and implications for the descriptive psychopathology of ON. Level of evidence V, Descriptive cross-sectional study. Keywords Orthorexia nervosa · Assessment · Eating habits questionnaire · Structural equation modeling · BMI · Psychopathology Introduction Psychopathology of ON Originally orthorexia is a neologism coined from the Greek which literally means “correct appetite”. Orthorexia nervosa (ON) is now used to describe “the pursuit of an extreme dietary purity”, “an obsessive and unsafe focus on eating foods perceived as healthy” [1]. ON is prompted by a desire to optimize one’s own physical health and well-being, but it is not accounted for by religious beliefs or concerns about environmental protection. ON may, therefore, be considered as a specifc form of healthism, which involves high aware- ness and enthusiasm in seeking information about health and illness [2]. Although ON is not listed among DSM-5 eating disorders [3], it can lead to severe impairments of both mental and This article is part of topical collection on Orthorexia Nervosa. Electronic supplementary material The online version of this article (https://doi.org/10.1007/s40519-020-00909-4) contains supplementary material, which is available to authorized users. * Valérie Godefroy vlrgodefroy@gmail.com 1 Inserm, U 1127, CNRS, UMR 7225, Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, FRONTlab, 75013 Paris, France 2 Department of Information Systems, Supply Chain and Decisions, NEOMA Business School, 76100 Rouen, France 3 Université de Paris, LPPS, 92100 Boulogne-Billancourt, France