We examined the relative contributions of genetic and environmental influences to restrained eating. Restrained eating was assessed by the Restraint Scale in a survey mailed to all twins enrolled in the University of Washington Twin Registry. We used structural equation modeling to estimate genetic and non-genetic contributions to restrained eating. 1,196 monozygotic, 456 same-sex dizygotic twins, and 447 opposite-sex twins were included in analyses. Restraint Scale scores were more closely correlated in monozygotic twins (rmale = 0.55, rfemale = 0.55) than in same-sex dizygotic twins (rmale = 0.31, rfemale = 0.19). Based on structural equation modeling, the estimated heritability for restrained eating, adjusted for BMI and sex, was 43% (95% confidence interval 35–50%). There was little evidence for common environmental effects. These results indicate an inherited component to restrained eating. Genes could influence restrained eating directly or through inherited mediators such as personality factors or tendencies to gain weight.
Genetic and environmental influences on restrained eating behavior. Int J Eat Disord. 2009; 42(8):765-772.