Overall proportion of orthorexia nervosa symptoms: A systematic review and meta-analysis including 30 476 individuals from 18 countries

José Francisco López-Gil; Pedro Juan Tárraga-López; Maria Soledad Hershey; Rubén López-Bueno; Héctor Gutiérrez-Espinoza; Antonio Soler-Marín; Alejandro Fernández-Montero; Desirée Victoria-Montesinos

doi:10.7189/jogh.13.04087

Overall proportion of orthorexia nervosa symptoms: A systematic review and meta-analysis including 30 476 individuals from 18 countries

J Glob Health. 2023 Nov 3:13:04087. doi: 10.7189/jogh.13.04087.

Affiliations

¹ Navarrabiomed, Hospital Universitario de Navarra, Universidad Pública de Navarra, Instituto de Investigación Sanitaria de Navarra, Pamplona, Navarra, Spain.
² Department of Environmental Health, Harvard University T.H. Chan School of Public Health, Boston, Massachusetts, USA.
³ One Health Research Group, Universidad de Las Américas, Quito, Ecuador.
⁴ Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla-La Mancha, Albacete, Spain.
⁵ University of Navarra, Department of Preventive Medicine and Public Health, School of Medicine, Pamplona, Spain.
⁶ Department of Physical Medicine and Nursing, University of Zaragoza, Zaragoza, Spain.
⁷ Escuela de Fisioterapia, Universidad de las Américas, Quito, Ecuador.
⁸ Faculty of Pharmacy and Nutrition, Universidad Católica San Antonio de Murcia, Murcia, Spain.
⁹ Department of Occupational Medicine, University of Navarra, Instituto de Investigación Sanitaria de Navarra, Pamplona, Spain.

Abstract

Background: To date, no previous meta-analysis has determined the overall proportion of orthorexia nervosa symptoms on a global scale. The aim of the present study was 2-fold: first, to establish the overall proportion of orthorexia nervosa symptoms on a global scale, assessed with the ORTO-15 questionnaire; and second, to determine the role of sex, type of population, mean age, body mass index, and the temporal trend in relation to orthorexia nervosa symptoms.

Methods: Four databases were searched (PubMed, Scopus, Web of Science, and Cochrane Database of Systematic Reviews) with date limits from January 2005 to June 2023. Studies assessing the proportion of orthorexia nervosa assessed using the ORTO-15 questionnaire with a cutoff of <35 or <40 points were included in this review.

Results: The overall proportion of orthorexia nervosa symptoms (using the cutoff <35 points) was 27.5% (95% confidence interval (CI) = 23.5-31.6, I² = 97.0%). In addition, no significant differences were observed between females (34.6%, 95% CI = 29.5-39.8, I² = 96.1%) and males (32.1%, 95% CI = 26.5-38.1, I² = 93.1%). According to the type of population, the highest overall proportion was found in people focused on sports performance or body composition (34.5%, 95% CI = 23.1-47.0, I² = 98.0%). Notwithstanding, caution should be exercised in interpreting this result, as reverse causality could be a potential pitfall in this relationship.

Conclusions: We found that approximately three out of 10 study participants showed orthorexia nervosa symptoms according to the ORTO-15 tool. This overall proportion was higher in those participants who were athletes or fitness practitioners. Over the years, the proportion of orthorexia nervosa symptoms seems to be increasing. These high percentages and their increase are worrisome from a public health perspective and highlight the need to develop psychometric instruments to aid in clinical diagnosis and treatment efficacy.

Registration: PROSPERO (CRD42022350873).

Publication types

Meta-Analysis
Systematic Review

MeSH terms

Exercise
Feeding Behavior
Feeding and Eating Disorders* / epidemiology
Female
Health Behavior*
Humans
Male
Orthorexia Nervosa
Surveys and Questionnaires