Shared Genetic Effects Between Age at Menarche and Disordered Eating

Purpose: An early age at menarche is associated with disordered eating in women. However, it is unclear whether they share genetic factors. The goal of the current study was to delineate the genetic correlation between age at menarche and disordered eating. Methods: Participants included 427 monozygotic and 329 dizygotic 16-17-year-old female twins from the Swedish Twin Study of Child and Adolescent Development. Disordered eating was assessed with the Eating Disorder Inventory-2. Age at menarche was assessed through self-report. A bivariate correlated factors model was used to delineate the genetic correlation between age at menarche and disordered eating. Results: The analysis revealed a negative genetic correlation of -.18 in the best-fit model, indicating that the genetic factors that influence younger age at menarche are associated with increased liability for disordered eating. Conclusions: Future research should examine possible causes for this correlation, such as the estrogen system and gene-environment interactions. Published by Elsevier Inc. on behalf of Society for Adolescent Health and Medicine.