Family Background and Racial and Ethnic Differences in Weight

Martin, Molly, Gary D. Sandefur, and Ann Meier
Working paper no. 2002-11


Medical and social research has found racial and ethnic differences in weight relative to stature. While previous research has controlled to varying degrees for family socioeconomic status, other observed and unobserved differences across families could help explain the observed racial and ethnic differences in weight. The present research seeks to better analyze the social factors associated with adolescent weight. We model adolescents’ body-mass index (BMI) utilizing sibling resemblance models of sibling pairs identified in the National Longitudinal Study of Adolescent Health. By conducting sibling model analysis in the structural equation framework, we are able to account for unmeasured family background characteristics and parcel out what proportion of the variation in adolescent weight is due to variation between families and variation within families. After accounting for both observed and unobserved characteristics of families, we find that blacks and Hispanics have significantly greater weights relative to whites, though the differences between these two racial groups are smaller than found in previous research. Pairs with other racial identities or mixed racial/ethnic identities show no significant differences in weight relative to whites once the observed and unobserved characteristics of families are accounted for.