Mina Farrokhi - PhD Student, Department of Psychology, United Arab Emirates Branch, Islamic Azad University, Dubai, UAE.
Amin Rafieipoor - Assistant Professor, Department of Psychology, Payame Noor University, Tehran, Iran.
Mohammad Reza Seyrafi - Assistant Professor, Department of Psychology, Karaj Branch, Islamic Azad University, Alborz, Iran.
Hasan Ahadi - Assistant Professor, Department of Psychology, Karaj Branch, Islamic Azad University, Alborz, Iran.
Adis Kraskian Moojembari - Assistant Professor, Department of Psychology, Karaj Branch, Islamic Azad University, Alborz, Iran.

Background: Nutrition education is a key component of health promotion programs and leads to improvement of nutritional behaviors of adolescents. Understanding the stages of cognitive-behavioral therapy in eating behavior and weight loss in adolescents is important. Objectives: The purpose of this study was to compare the effectiveness of the transtheoretical model and cognitive-behavioral therapy on eating behavior and weight loss in adolescents.Method: The research method was semi-experimental with a pre-test and post-test design with a two-month follow-up with the control group. The statistical population consisted of all adolescents referred to counseling centers in Mashhad in autumn ۲۰۱۹; ۴۵ of them were selected by convenience sampling method and were divided into ۳ experimental, second, and control groups. The research questionnaires were Cappelleri et al.'s (۲۰۰۹) eating behavior questionnaire. Data analyzed by analysis of covariance test using SPSS.۲۵ software. Results: The results showed that the effectiveness of the transtheoretical model and cognitive-behavioral therapy was different on eating behavior so that cognitive-behavioral therapy is more effective than the transtheoretical model (p <۰.۰۰۱).Conclusions: Cognitive-behavioral therapy on eating behavior and weight loss of adolescents was more effective in comparison with the model of the change process. It is suggested that cognitive-behavioral therapy should be considered in the treatment of appropriate principles of nutrition and control of adolescents' weight.

Adolescent, Weight Loss, Feeding Behavior, Cognitive Behavioral Therapy, Transtheoretical model