Are orthorexia nervosa symptoms associated with deficits in inhibitory control?

Disordered eating and the meat-avoidance spectrum: a systematic review and clinical implications

PURPOSE

Meat avoidance has long been thought to be related to eating psychopathology; however, research does not necessarily support this notion. Furthermore, commonly used eating disorder scales may be picking up on normal meat-avoiding behaviours in vegetarians and vegans. As such, we systematically reviewed the association between vegetarianism, veganism, and disordered eating, and reviewed the psychometric properties of eating disorder scales for use in these populations.

METHODS

We searched electronic databases MEDLINE, PsychINFO, and CINAHL for literature published until June 2021.

RESULTS

Forty-eight studies met eligibility criteria, with no consensus as to whether meat avoidance was associated with higher rates of disordered eating. Most studies reported a significant positive association with both vegetarianism and veganism, and orthorexia nervosa. Six studies provided evidence for the use of eating disorder measures in vegetarians and vegans, reporting poor psychometric fit among all scales.

CONCLUSION

This systematic review highlights the extent to which vegetarians and vegans have been highly understudied, with limited research suggesting higher levels of orthorexia nervosa behaviours in vegetarians and vegans. Furthermore, our results provide tentative evidence that the factorial validity of commonly used eating disorder scales, such as the EDE-Q, may be poor in vegans.

LEVEL OF EVIDENCE

Level I, systematic review.

Orthorexia nervosa and executive dysfunction: symptomatology is related to difficulties with behavioral regulation

PURPOSE

This research explored whether orthorexia nervosa is associated with deficits in executive function.

METHODS

A non-clinical sample of participants (n = 405; 80% women, 53% white, mean age = 24, mean body mass index = 25) completed the Orthorexia Nervosa Inventory (ONI) and the Behavior Rating Inventory of Executive Function-Adult version (BRIEF-A).

RESULTS

ONI scores were weakly to moderately correlated with all BRIEF-A scales (p < 0.001 for eight scales, p < 0.05 for one scale), exhibiting the greatest correlations with the scales assessing behavioral regulation: Emotional Control (r = 0.34), Inhibition (r = 0.30), Set Shifting (r = 0.25), and Self-Monitoring (r = 0.28). Hierarchical regression analyses revealed that eight of these nine relationships remained significant (p < 0.001 for five scales including all behavioral regulation scales, p < 0.01 for two scales, p < 0.05 for one scale) after controlling for demographic variables (e.g., gender, body mass index, age, education level) and diagnoses of an eating disorder, obsessive-compulsive disorder, attention deficit/hyperactivity disorder, autism, and learning disability.

CONCLUSION

These findings suggest that, despite unique manifestations, orthorexia and anorexia may possess an overlapping neuropsychological profile marked by deficits in executive function, which may negatively impact daily life.

LEVEL OF EVIDENCE

Level V, descriptive cross-sectional study.

Orthorexia Nervosa and its association with obsessive-compulsive disorder symptoms: initial cross-cultural comparison between Polish and Italian university students

There is limited evidence of a link between Orthorexia Nervosa (ON) and Obsessive-Compulsive Disorder (OCD), and no definitive conclusions can be drawn. The interplay between socio-cultural context and ON has been poorly investigated as well. Therefore, the objectives of the present study were: (1) to investigate the differences in ON and OCD symptoms and (2) to assess the relationship between ON and OCD symptoms among university students. Six hundred and sixty-six university students participated in the present study: 286 from Poland and 320 from Italy. No age, gender and marital status differences were identified between two samples of university students. However, on average, Polish university students had a higher Body Mass Index than Italian ones. Our findings showed that Polish students present more problems related to obsessive symptomatology, core beliefs of OCD, perfectionism traits, and a major ON symptomatology than Italian ones. Also, Polish students with a higher level of ON exhibited higher levels of OCD symptoms and parental expectations/parental criticism. While Italian students with a higher level of ON showed higher levels of perfectionism features (organization and concern over mistakes). In general, correlations were low as confirmation of partial independence ON from OCD symptoms and core beliefs of OCD in both Polish and Italian university students. The present results highlight a need for further investigation of the correlates of ON across different cultural groups. Future research may screen individuals with ON to determine the comorbidity between ON and OCD symptomology to facilitate appropriate treatment choices. LEVEL OF EVIDENCE: Level V, Opinions of respected authorities, based on descriptive studies, narrative reviews, clinical experience, or reports of expert committees.

Validation of the Turkish version of the Orthorexia Nervosa Inventory (ONI) in an adult population: its association with psychometric properties

PURPOSE

To examine the reliability and validity of the Turkish version of the Orthorexia Nervosa Inventory (ONI) in a large adult population.

METHODS

Included in this cross-sectional study, were 710 individuals living in Turkey who were between 18 and 65 years of age. The individuals were reached via an online questionnaire that included their sociodemographic characteristics and the ONI and Eating Attitude Test-26 (EAT-26). Confirmatory factor analysis (CFA) was used to test the validity of the ONI. The ONI contains three sub-factors (behaviors, emotions, and impairments). Analyses were conducted using LISREL 8.80 for Windows and IBM SPSS Statistics for Windows 22.0.

RESULTS

The Cronbach's alpha coefficient was 0.91 for the ONI total factor scores and Cronbach alpha values for behaviors, impairments, and emotions were found to be 0.82, 0.84, and 0.81, respectively. The CFA performed supported the three-factor structure of the ONI obtained in the first sample. The minimum discrepancy per degree of freedom = 5.65 and the model generally fit well to the structure (RMSEA = 0.08, CFI = 0.94, NFI = 0.93, SRMR = 0.07, IFI = 0.94). A positive and moderate relationship (r = 0.42) was found between the ONI and EAT-26. A positive and low level (r = 0.16) correlation was found between the ONI and body mass index. There was no statistically significant difference between the ONI scores according to gender (p = 0.22).

CONCLUSION

The findings suggested that the Turkish version of the ONI is a valid and reliable scale for determining the tendency for ON in a Turkish adult population.

LEVEL OF EVIDENCE

Level V, descriptive cross-sectional study.

Validation of the Greek ORTO-15 questionnaire for the assessment of orthorexia nervosa and its relation to eating disorders symptomatology

PURPOSE

The aim of the study was the validation of the Greek version of the ORTO-15 questionnaire. An additional aim was to explore the relation between orthorexic and eating disorder behaviors in a sample of Greek students.

METHODS

ORTO-15 was translated and adapted in the Greek language. After its final version was drafted, its test-retest reliability was checked. Then, the questionnaire was administered to 120 students of psychology along with EAT-26. Additionally, demographics, BMI and information related to eating disorders were collected.

RESULTS

The Greek version of the ORTO-15 questionnaire showed acceptable internal consistency (Cronbach's a 0.7). Factor analysis produced a three-factor model similar to the original English version of the questionnaire. The correlation of ORTO-15 and EAT-26 revealed that higher measurements in the diet and bulimia EAT-26 scale were related to increased orthorexic symptomatology. Finally, there was no significant correlation between the 3 factors of the ORTO-15 (emotional, rational and behavioral) and age, education or Body Mass Index.

CONCLUSIONS

This study is the first attempt to assess orthorexia nervosa in a Greek student population. ORTO-15 was found to be a reliable tool for the measurement of orthorexia in Greece. Finally, in accordance with other studies, orthorexic symptoms were partially related to eating disorder symptomatology, thus raising the question of possible similarities and overlap between the two clinical constructs.

LEVEL OF EVIDENCE

Level V, Cross-sectional descriptive study.

Misinformation, thin-ideal internalization, and resistance to treatment: an interpretive phenomenological analysis of the experience of orthorexia nervosa

PURPOSE

Orthorexia nervosa (ON) is an emerging pattern of disordered eating which may be driven by a pathological desire to consume only highly nutritious foods, absent concern over body weight, as is noted in anorexia nervosa (AN). This study seeks to clarify the development and progression of ON and add to researchers' understanding of this potential disorder.

METHOD

Utilizing Interpretive Phenomenological Analysis to guide data collection and analysis, interviews were conducted with 18 individuals who self-identified as having ON.

RESULTS

Participants described a clear distinction between orthorexia nervosa and clinically recognized eating disorders, with which they had prior experience. In addition, they demonstrated patterns of inflexible thinking that guided their perceptions of themselves and others. As a result, participants rapidly integrated newly acquired nutritional information, which led to escalations in restriction, social isolation, and physical symptoms of malnutrition. While prior findings on the relationship between ON and weight are conflicting, previously proposed criteria for ON emphasize an absence of weight-related concerns. The results of the present study suggest that weight control is a primary motivating factor in the escalating pattern of restriction.

CONCLUSION

The nuanced results from this work evidence the value of interpretive qualitative approaches to improve understanding of ON. In particular, participants' described inflexible thinking with respect to eating behaviors may help inform or revise screening instruments and provide important insights for treatment of ON.

LEVEL OF EVIDENCE

Level V, qualitative descriptive research.

Introducing ORTO-R: a revision of ORTO-15 : Based on the re-assessment of original data

BACKGROUND

Orthorexia nervosa has attracted significant attention in the field, however, alongside increasing knowledge, more and more gaps are being identified. One of the fundamental problems concerns measurement of orthorexia nervosa. The most commonly used self-report measure, the ORTO-15, demonstrated an unstable factorial structure across different populations. Therefore, one might question whether the knowledge obtained from past research using ORTO-15 is valid or not. The aim of the present paper is to re-analyse original data used for the validation of ORTO-15 to assess its factorial structure and propose its revision, the ORTO-R.

METHODS

The description of the sample and procedure corresponds to the one reported in Donini et al. (Eat Weight Disord 10:28-32, 2005). N = 525 subjects were enrolled. To evaluate whether the factorial structure of ORTO-15, we used confirmatory factor analysis. The results revealed that the ORTO-15 indeed does not capture the structure of orthorexia nervosa adequately and revision is needed. The ORTO-R contains six items from ORTO-15, which were identified as the best markers of orthorexia nervosa.

DISCUSSION AND CONCLUSION

In the current paper, we present a refined measure of orthorexia nervosa-the ORTO-R. It is based on a frequently used ORTO-15, overcoming its main limitations. We strongly believe that the current work will act as a bridge, linking past with the future research, and that alongside a new measure, the field of research on orthorexia nervosa will move forward.

LEVEL OF EVIDENCE

Level V, descriptive study.