Network Associations Among Body Image, Lifestyle, Body Mass Index, and Quality of Life in Adolescents.

Background: Body image is known as an important factor affecting different aspects of adolescents' health; however, its relationship with lifestyle, body mass index (BMI), and health-related quality of life (HRQoL) in Iranian adolescents has not been addressed in a conceptual model.

Objectives: This study aimed to investigate the network associations among body image, lifestyle, BMI, and HRQoL in adolescent boys and girls.

Methods: The present study examined 760 adolescents (15 - 18 years) from Tehran. Adolescents reported their weight and height, according to which the participants' BMIs were calculated. The adolescents' body image, lifestyle, and HRQoL were assessed using a set of questionnaires, including the Body Image Scale for Youth (BISY), Modifiable Activity Questionnaire (MAQ), Eating Habits Checklist, Eating Attitudes Test (EAT-26), and Pediatric Quality of Life Inventory (PedsQL^TM).

Results: The participants' mean age and BMI were 16.5 ± 1.0 years and 22.4 ± 4.6 kg/m², respectively. More than one-third of boys (39.9%) and less than a quarter of girls (22.6%) were overweight/obese. In the final model, body image was significantly and directly associated with physical activity, disordered eating, eating habits, and HRQoL in both genders (P < 0.05). Moreover, body image was directly correlated with screen time in boys (P = 0.012) and BMI in girls (P = 0.001). Body image was indirectly correlated with BMI by the mediating role of disordered eating in girls. Moreover, body image was indirectly associated with HRQoL by the mediating role of physical activity and eating habits in both genders and screen time only in boys.

Conclusions: The network associations among body image, lifestyle, BMI, and HRQoL revealed a gender-specific pattern among the study population. Body image was a significant determinant of lifestyle and HRQoL in both genders and excessive weight in girls. The present findings would contribute to designing and implementing relevant health promotion interventions.