Family Influences On BMI and Habitual Dietary Intake Among Adolescents

Introduction: Family characteristics such as parenting style and family functioning (e.g., cohesion, flexibility) have been associated with adolescent dietary behavior. The present study examines the association of family influences with Body Mass Index (BMI), binge eating and obesity-related dietary behaviors (e.g., sugar sweetened beverages). Family influence variables associated with these outcomes can be incorporated into the design of a novel family-based obesity prevention program developed under the NIH-funded ORBIT initiative (Obesity Related Behavioral Intervention Trials).

 

Methods:

Data on family influences and dietary behavior were gathered from a study of high school students (n=158). Students were recruited from schools where a minimum of 25% free or reduced cost lunches were provided. Participants were 57% female, 68% Hispanic, 16 years of age (range 14-17), 57% in the normal BMI range, 18% overweight, and 25% obese. Outcome variables included BMI percentile, sugar sweetened beverages (SSB), high sugar/fat snacks, fruit and vegetable intake (F&V), and binge eating. Height and weight were measured directly to obtain BMI. The Youth Adolescent Questionnaire (Rockett), a validated food frequency assessment, provided estimates of dietary intake. The Binge Eating Diagnostic Scale (Stice) was used. Self-reports on family influence variables were obtained and included parenting style, FACES IV (cohesion, flexibility), friend and family support for healthy diet, home availability of snacks, perceived adolescent control over food intake, and family meal variables (frequency, priority, rules atmosphere).

Results: Correlation analyses tested associations between the family influence variables and each outcome. Family support (0.29, p<.0005), food availability (-0.18, p<.04), and parenting style (involvement subscale; 0.15, p<.05) were associated with BMI percentile. The FACES total ratio (balanced cohesion & flexibility adjusted for unbalanced dimensions; -0.31, p<.0005), and parenting style (autonomy subscale -0.17, p<.04; involvement subscale -0.20, p<.02) were related to binge eating. Family support (-0.17, p<.03) and food availability (0.18, p<.05) were related to SSB consumption and only availability was related to snack consumption (0.41, p<.0005). No significant correlates were identified for F&V consumption although family support approached significance (0.17, p<.06).

Conclusions: Family support, availability of snacks and parenting style were consistent correlates of obesity-related dietary intake, binge eating and BMI. If confirmed in multivariate analyses, these variables can help guide intervention design with implications for parent-child interactions (parenting style), family support, and control of the home food environment.