Despite limited research in Orthorexia Nervosa and nutrition and dietetic students, some promising strides have been made in the way of examining those students in the health sciences and Orthorexic behaviors. Orthorexia nervosa is a recently recognized as eating disorder, where the quality of food becomes an obsession, and it is characterized by highly worries about healthy nutrition and eating attitudes. The current study was attempted to evaluate the prevalence of ON among students and nutritionist in Jordan. To the best of our knowledge, this study was the first to address ON among Jordanian nutrition students and nutritionists.
Few researchers have examined nutrition and dietetic students’ incidence of Orthorexia. The results obtained in this research in ORTO-15 test at (35/40) point cut-off thresholds - following the scientific approach of other literatures [5, 10, 20, 23–25]. We recorded a 72.0% prevalence of ON at cut-off 40-point threshold, there was almost 3-fold decrease in the ON tendency at the 35-point threshold (31.8%). Similarly, many studies have not been satisfied with ORTO-15 questionnaire and its cut-off point as an instrument tool for measurement the ON [11, 26, 27]. Particularly, Dell'Osso, Abelli  have shown that a 35 cut-off, as compared to 40, can maximize specificity and sensitivity . Furthermore, many studies recorded a decrease in the prevalence of ON to about two to three folds when they fix the cut-off at 35, as compared to the cut-off at 40 [11, 24, 25, 27].
Our results aligned to those studies indicating no Orthorexic features based on gender at 40-point threshold; but this was not the case at 35-point threshold. In males, ON tendency at 35-point threshold was 39.4%, compared to 28.6% in females 28.6% (p = 0.029), and this was evident by MANOVA analysis, which showed a clear significant effect of the gender as dependent variable on the ON tendency (p = 0.043) (Tables 5 and 6). While we revealed a significant gender effect on the ON tendency; there is contradictory results between different studies in linking ON prevalence with gender; some authors have speculated a higher prevalence of ON among males [7, 28]; or females . Whereas others revealed no significant gender differences [5, 10, 20, 23]. Due to Kamarlı Altun, Keser , the reason for these differences may be due to the socio-demographic and cultural differences between the sample groups in the studies.
Notwithstanding, Dell'Osso, Abelli  approved that females have more interest on healthy nutrition as they more careful about their body image and weight control. Also, this was indicated by Brytek-Matera, Donini , in a sample of university students, by which females have a strong preoccupation with healthy diet and it was positively correlated with physical appearance evaluation and body satisfaction.
As a confirm of our observations, the fact that ON was present among male university population, Ramacciotti, Perrone  hypothesized that ON in men could be related to health issues. Moreover, men take care of being healthfully by following accepted terms of beauty (culturally and socially). A different hypothesis explained that orthorexic behaviors in men is associated with characteristics of obsessive-compulsive personality and polarization to “masculine ideals” such as muscularity, strength, power and sportsmanship 
The current study revealed a significant difference recorded between the BMI categories and ON tendency at 35-point threshold (p = 0.007). ON tendency increased gradually from 15.2%, 30.5%, 35.5–55.2% for underweight, normal weight, overweight to obese; respectively (p = 0.007). Also, depending on the cut-off at 40-point threshold the ON tendency was higher on all BMI categories despite that there were no significant differences between different categories as shown in Table 4. Many previous studies did not reveal differences in the occurrence of ON tendency between BMI categories, for both cut-off point at 35 and 40 points [20, 25, 31]
Clearly, mixed findings can be shown in the previous studies; the current findings were in parallel with the results that showed a positive correlation between ON symptomatology and BMI [6, 7, 20, 28, 32]. On the contrary, many studies revealed no significant differences [5, 11, 24].
This study has several limitations including: the cross-sectional design, which could not assess causality of relationships, small sample size and choosing to participate, is a bias that might increase or decrease responses from students or nutritionists with ON. Despite these limitations, this study has several notable strengths, including it’s the first study to investigate prevalence of ON in Jordan and particularly among nutrition field members.