Body Size Dissatisfaction Across BMI Status Among Shanghai Adolescents: Family Functioning and Accuracy of BMI Perception As Independent Predictors

Purpose: Body size dissatisfaction (BSD) has been identified as a significant risk factor for eating disorder. Most studies were based on clinical population, particularly female adolescents and young women suffering from eating disorder. Recent studies called for examining the role of individual and familial attributes in BSD in the general population for more effective prevention of overweight and obesity. A 10-year longitudinal study reported that the family environment contributed significantly to BSD in adolescence in the USA. Another understudied area was to explore the gender differences for adolescents from a cross-country perspective. Only three studies reported BSD among adolescents in urban China. This study was the first research to examine the relationship between BSD and family functioning across BMI statuses and body size perception among Shanghai adolescents.  

Methods: A cross-sectional study was completed in five Shanghai schools with 1,312 adolescents (705 boys and 607 girls) aged 11 to 15 between June 2013 and May 2014. Body weight and height were measured for the calculation of BMI. Both adolescent and his/her parent evaluated family functioning by filling out the Systemic Family Dynamics Questionnaire; Family Assessment Device; Paternal and Maternal Psychological Control Scales; and Chinese Paternal and Maternal Control Scales. The adolescents also completed the Children's Body Image Scale, a body-image assessment tool consisting of seven gender-specific images of children ranging from very thin to obese. Subtracting the ideal body image from the current body image yielded the BSD score. Perception was calculated by comparing the chosen body figure with the actual BMI. Logistic regression analyses by gender were conducted to calculate adjusted odds ratios (AOR) for three categories, “wanting to be thinner”, “satisfied” and “wanting to be bigger” (dependent variable in three separate models), controlling for parental BMI, parental education level, born in Shanghai, BMI perception, age, current BMI status and family functioning.

Results: BSD was prevalent among Shanghai adolescents, particularly for female adolescents (65%). Family functioning, BMI perception and BMI were found as independent predictors of BSD. Gender differences were identified. Male (female) adolescents wanted to be bigger: AOR = 0.12 (AOR = 0.03) for overestimation, AOR = 10 (AOR = 8) for underestimation. Male (female) adolescents wanted to be thinner: AOR = 25 (AOR = 0.08) for overestimation, AOR = 0.04 (N.A.) for underestimation. Both genders with better perceived family functioning were more likely to be satisfied with their body size (AOR = 2 and AOR =3). Males experiencing higher behavioral control from parents were more likely wanting to be bigger (AOR = 3).  

Conclusion and Implications: To tackle the prevalence of BSD and the rising overweight and obesity epidemic in urban China, family-based intervention is recommended. The enhancement of healthy family functioning can help promote less conflict avoidance and more mutual problem solving among family members, and less parental control and more equalitarian communication between parents and adolescents. Intervention must also be targeted at improving the accuracy of body perception and challenging the dominant cultural image of preferred bigger body size, especially male adolescents.