The relation of orthorexia with lifestyle habits: Arabic versions of the Eating Habits Questionnaire and the Dusseldorf Orthorexia Scale

BACKGROUND: Some of the commonly used tools to assess orthorexia nervosa (OrNe) do not allow a meaningful interpretation of the scores or yield mixed results about the dimensions needed to represent orthorexia. Since no advancement in the theoretical knowledge can be made without a thorough examination of the measurement aspects, this study aimed to evaluate the correlation between orthorexia nervosa (OrNe) and lifestyle habits, notably alcohol drinking, cigarette and waterpipe smoking, and physical exercise, and to validate and assess the psychometric properties of the Arabic versions of the Eating Habits Questionnaire (EHQ) and Düsseldorf Orthorexia Scale (DOS). METHODS: A total of 456 adult participants completed a self-administered questionnaire. Exploratory structural equation models were used to test the internal structure of the instruments. Shorter and more explicit versions were proposed for instruments. Pearson and partial correlations were computed between orthorexia scores and healthy behaviors scores. RESULTS: Regarding the internal structure of both EHQ and DOS, evidence favored the bi-dimensional construct of orthorexia. Both tools presented two theoretically clearly interpretable factors (OrNe and Healthy Orthorexia—HeOr—). The two questionnaires presented a high convergent validity, as dimensions with the same interpretation were correlated around 0.80. While OrNe was positively correlated with the use of unhealthy substances (higher alcohol use disorder, cigarette, and waterpipe dependence), HeOr was negatively associated with these behaviors. CONCLUSION: Our results emphasize the idea that further attention should be paid to the multidimensional structure of orthorexia, as OrNe and HeOr present an opposite pattern of associations with healthy behaviors. An OrNe etiopathogenesis common to eating disorders can explain these differences.