Duration of Breastfeeding and Subsequent Adolescent Obesity: Effects of Maternal Behavior and Socioeconomic Status

Abstract Purpose Previous research has shown that longer duration of breastfeeding is associated with less risk of obesity in childhood and adolescence. However, although putative physiological mechanisms have been proposed, less work has focused on psychosocial or environmental factors, including socioeconomic status (SES) and stressful family environments. Methods The current study examined the role of observed maternal emotional behavior and SES (parental education) in the association between duration of breastfeeding and adolescent body mass index (BMI). One hundred fifteen mothers and adolescents participated in interaction tasks when adolescents were approximately 12 years of age. We measured adolescent BMI at approximately 15 years of age and, at one point over the course of the study, mothers retrospectively reported on duration of breastfeeding. Results Controlling for adolescent gender, age, physical activity, number of perinatal complications, SES, birth weight, and mother's depressive symptoms, longer duration of breastfeeding was associated with lower adolescent BMI ( p  = .019), and this association was moderated by the mother's observed behavior during interactions with her adolescent, such that greater frequency of dysphoric behavior was associated with a stronger association between breastfeeding and adolescent BMI ( p  = .002). Longer duration of breastfeeding mediated the association between higher family SES and lower adolescent BMI. Conclusions This study is the first to show that observed parental behavior during adolescence may be an important moderator of the association between breastfeeding and obesity. The findings provide justification for future intervention research examining family environment factors in improving adolescent health.