Understanding the relationship between nutritional knowledge, self-efficacy, and self-concept of high-school students suffering from overweight.

Background and Aim: Adolescents' overweight problems have been paid much attention due to their significant increase in recent decades in developed countries. Poor eating patterns subsequently affect their self-efficacy and self-concept. Therefore, paying attention to the nutritional knowledge of overweight students in this period is essential. This study examines the relationship between self-efficacy, self-concept, and nutritional knowledge of overweight students in the city of Isfahan. Materials and Methods : The 140 overweight students who participated in this descriptive, analytical study with were randomly selected from one of five areas of Isfahan city in the year 2011-2012. Questionnaires for data collection in this study included demographic form, nutrition knowledge, Cooper Smith self-esteem, and general self-efficacy questionnaire. Data were analyzed by ANOVA, regression, and Pearson's correlation coefficient with statistical package in social sciences version 18. Results: There was a significant correlation between whole nutritional knowledge and self-efficacy ( r = 0.29, P > 0.001) and self-concept ( r = 0.26, P = 0.002). There was a significant correlation between self-efficacy and self-concept ( r = 0.3, P = 0.001). Furthermore, in the selection of food section there was no significant correlation with the self-concept ( r = 0.147, P = 0.083). Regression analysis between self-concept, self-efficacy, family dimension, father's education, mother's education, father's occupation, mother's occupationa and income with nutrition knowledge showed that these eight variables explain 17.7% of the variance in health behaviors totally. Conclusion: By conducting this study, and revealing the direct relationship between nutritional knowledge, self-concept, and self-efficacy, we could conclude that if nutritional knowledge of overweight students is promoted, this factor would lead to an increase their self-concept and self-efficacy in order to adopt healthy behaviors and have the expected healthy eating and healthy life-style.