Puberty and the Genetic Diathesis of Disordered Eating Attitudes and Behaviors

Twin studies from the Minnesota Twin Family Study (MTFS) suggest negligible genetic effects on eating pathology before puberty but increased genetic effects during puberty. However, an independent study found no pubertal differences in genetic and environmental effects (R. Rowe, A. Pickles, E. Simonoff, C. M. Bulik, & J. L. Silberg, 2002). Discrepant results may be due to methodological differences. The MTFS studies divided twins at mid-puberty, whereas R. Rowe et al. (2002) divided twins based on menarche alone. In the present study, the authors aimed to reconcile discrepant findings by examining differences in etiologic effects for disordered eating attitudes and behaviors (i.e., levels of weight preoccupation, body dissatisfaction, binge eating, compensatory behaviors) using both classification methods in a new sample of 656 female twins. Using the MTFS method (i.e., K. L. Klump, M. McGue, & W. G. Iacono, 2003), the authors observed nominal genetic effects in prepubertal twins but significant genetic effects in pubertal and young adult twins. Conversely, genetic effects were moderate and equal in all groups using the R. Rowe et al. (2002) method. Findings highlight the potentially important role of puberty in the genetic diathesis of disordered eating attitudes and behaviors and the need to use early indicators of pubertal status in studies of developmental effects.