Orthorexia nervosa (ON) may precede, ensue, or coexist with eating disorders (ED) and also affect eating behaviors. The aim of this study was to explore the dietary patterns (DPs) and other eating habits of people showing ON tendency, ED symptoms, and both ON tendency and ED symptoms, as well as those not showing either. The data for the study were collected from a sample of 1120 Polish college students through a cross-sectional survey in 2017. The questionnaire used in the survey included the ORTO-15, the Eating Disorder Screen for Primary Care (ESP), and the Food Frequency Questionnaire (FFQ-6), and the students were also asked questions about their eating habits and special diets. A factor analysis was conducted to identify the following five DPs: "high-sugar products and refined products," "meat and meat products," "alcohol," "high-fiber products and nuts," and "dairy products and whole-meal bread." Univariate logistic regression analyses were carried out to verify the associations between the variables. Students in the "ON and without ED" group were found to exhibit more healthy eating habits than the students in the "ED and without ON" group. The use of a special diet in the past and currently increased the risk of displaying ON tendency and ED symptoms. Students in the "ON and without ED" and "ON and ED" groups were characterized by less frequent consumption of high-sugar and refined products. Students who rarely consumed meat and related products were found to be less likely to display "ON and ED." In conclusion, different eating habits shown by people with ON tendency and ED symptoms confirmed the difference between ON and ED. However, the simultaneous displaying of ON and ED leads to the overlapping of specificity of eating habits, which can make the diagnosis based only on the eating habits difficult. Thus, there is still a need for further research involving the use of more sensitive tools that can better identify ON tendency and ED symptoms, as well as DPs.
Keywords: dietary patterns; eating disorders symptoms; eating habits; orthorexic tendency; students.