Discussion In this large, nationwide cohort of adolescents/young adults, we observed that adolescents/young adults from families with high family functioning and high-quality of fam and father-adolescent relationships were Ness mother kely to have overweight or obesity and less likely to engage in unhealthful weight-related behaviors, although the pattern of these associations differed b Asso ciations between family functioning and weight-related behaviors were similar for males and females; however, family functioning was associated with weight status among females only. Both males and females who reported positive relationships with their parents reported better weight related behaviors. Females were affected equally by the quality of their relationship with their mothers and fathers whereas for males, weight status may be more affected by their relationship with fathers Our results are consistent with previous studies with smaller samples, which found that adolescents from families with high family functioning are less likely to engage in disordered eating behaviors[15 16]. Epide- miologic studies exploring associations between family functioning and adolescent weight are few in number 128-31] and our results extend this research by exami ning this association in a large, nationwide sample. Simi lar to our results, in their sample of ethnically-diverse Minnesota youth, Berge and colleagues 129] found that family functioning was associated with while higher healthier eating and activity behaviors among both males and females, higher family functioning was associated with lower prevalence of overweight/obesity among females only. While family dysfunction may interfere with healthful behavior for both males and females due to the families limited ability t organize and plan routines related to these behaviors, the stronger asso ciation between family function and weight among females may be due to stronger reactivity and response to stress among females.