The main objective of the present study was to analyse the role of the ego-dystonicity and ego-syntonicity of eating disorder intrusive thoughts (EDITs) in the genesis and maintenance of eating disorders (EDs). Participants were 98 female patients with EDs, 56 Spanish and 42 English (27.19 +/- 9.59 years; body mass index (BMI): 18.72 +/- 2.87). All of them completed the eating attitudes test, the Eating Attitudes Test, the Eating Intrusive Thoughts Inventory, the Ego-Dystonicity Questionnaire-Reduced version, and the Ego-Syntonicity Questionnaire. Patients indicated that their EDITs were rational and also undesirable and immoral, suggesting that EDITs are not fully ego-syntonic or ego-dystonic. Multivariate analysis of variance (MANOVA) indicated no differences in ego-syntonicity and ego-dystonicity across ED subtypes. Path analyses were performed to investigate the mediating role of the EDITs' ego-syntonicity and ego-dystonicity in their interference, dysfunctional appraisals and control strategies. They showed, first, that the more interference an EDIT caused, the more ego-syntonic and the less ego-dystonic it was and, second, that when the EDITs were assessed as ego-syntonic, patients tried to do what they indicated, whereas when they were assessed as ego-dystonic, patients made efforts to neutralise them. Clinical implications for the conceptualisation and treatment of ED are discussed. (C) 2013 Elsevier Ireland Ltd. All rights reserved.