Effectiveness of an Educational Package for Coping with Orthorexia Nervosa on Symptom Severity and Irrational Health Beliefs: An Experimental Study

Afarin  Aghamohammadsadegh; Fatemeh Dehghani Arani; Masoud Gholamali Lavasani; Gholamali Afrooz

Authors

Afarin Aghamohammadsadegh Ph.D.Student in Health Psychology,Kish International Campus,University of Tehran Author https://orcid.org/0009-0007-6786-4902
Fatemeh Dehghani Arani Associate Professor, Faculty of Psychology and Educational Sciences, University of Tehran https://orcid.org/0000-0002-6641-2345
Masoud Gholamali Lavasani Associate Professor, Faculty of Psychology and Educational Sciences, University of Tehran Author https://orcid.org/0000-0003-0958-1027
Gholamali Afrooz Professor, Faculty of Psychology and Educational Sciences, University of Tehran Author https://orcid.org/0000-0003-2386-3223

Keywords:

Orthorexia Nervosa, Irrational Health Beliefs, Educational Intervention, Bodybuilding, Repeated Measures, Psychological Treatment

Abstract

Purpose: The present study aimed to evaluate the effectiveness of an educational package for coping with orthorexia nervosa in reducing orthorexia nervosa symptom severity and irrational health beliefs among adults attending bodybuilding clubs in Tehran.

Methods and Materials: This quasi-experimental study employed a two-group pretest–posttest design with a three-month follow-up. The statistical population consisted of adults aged 18–40 years who were regularly active in bodybuilding clubs in District 1 of Tehran. Using convenience sampling and subsequent screening, 72 eligible participants were selected and randomly assigned through block randomization to an experimental group (n = 36) and a control group (n = 36). The experimental group received the educational package for coping with orthorexia nervosa in ten 75-minute group sessions held twice weekly, whereas the control group received no intervention during the study period. Data were collected using the Orthorexia Nervosa Scale and the Health Irrational Beliefs Scale at pretest, posttest, and three-month follow-up. Data were analyzed using repeated-measures analysis of variance and Bonferroni-adjusted pairwise comparisons in SPSS version 26.

Findings: Repeated-measures analysis showed significant group × time interactions for orthorexia nervosa symptom severity, F(2,140) = 52.79, p < 0.001, partial η² = 0.430, and irrational health beliefs, F(2,140) = 29.34, p < 0.001, partial η² = 0.296. In the experimental group, orthorexia nervosa symptoms decreased significantly from pretest to posttest (p < 0.001) and remained significantly lower at follow-up (p < 0.001), although a small significant increase occurred from posttest to follow-up (p = 0.033). Irrational health beliefs also decreased significantly from pretest to posttest and follow-up (both p < 0.001), with no significant difference between posttest and follow-up (p = 0.574).

Conclusion: The educational package was effective in reducing orthorexia nervosa symptom severity and irrational health beliefs, and most of the observed improvements were maintained over the three-month follow-up period.

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