【关键词】  genetics

    the pision of Epidemiology, Stockholm Centre of Public Health, Sweden (ST and PT)
    the Child and Adolescent Public Health Epidemiology Group, Department of Public Health Sciences, Karolinska Institute, Stockholm, Sweden (FR)
    the Health Care Research Unit, Department of Body Composition and Metabolism, Institute of Internal Medicine, The Sahlgrenska Academy at Gteborg University, Gteborg, Sweden (JK).

    ABSTRACT

    Background: Eating behavior may be implicated in the increasing prevalence of overweight and obesity, presumably in relation to easy access to energy-dense and highly palatable foods.

    Objective: The aim of the present study was to disentangle genetic and environmental influences on eating behavior in a population-based cohort of male twins.

    Design: The study included 326 dizygotic and 456 monozygotic male twin pairs aged 2329 y from Sweden. The revised 21-item version of the Three-Factor Eating Questionnaire (TFEQ-R21) was used to assess eating behavior. This validated instrument consists of 3 dimensions: cognitive restraint, emotional eating, and uncontrolled eating. Structural equation modeling was used to estimate the heritability of eating behavior.

    Results: Cognitive restraint was the only TFEQ-R21 scale that significantly correlated with BMI (r = 0.39, P < 0.0001). The best-fitted models gave a heritability of 59% (95% CI: 52%, 66%) for cognitive restraint, 60% (95% CI: 52%, 67%) for emotional eating, and 45% (95% CI: 36%, 53%) for uncontrolled eating.

    Conclusions: These results show the great importance of genetic factors in the eating behavior of a large, unselected population of young adult male twins. Nonshared environmental factors were also important, whereas shared environmental factors did not contribute to eating behavior.

    Key Words: Eating behavior  twins  males  genetics  heritability  structural equation models

    INTRODUCTION

    The global increase in the occurrence of overweight and obesity during the past few decades is probably explained by environmental factors and interactions between genes and environments. Previous twin and adoption studies reported heritabilities of body mass index (BMI) and obesity in the range of 3080% (1, 2). Differences in genetic susceptibility to obesity may explain why some inpiduals develop obesity while others do not (3).

    Heredity seems to affect nearly all aspects of food intake regulation (4, 5). A study of middle-aged and older US male and female twins showed that 48% of the variability in healthy eating patterns could be attributed to genetic factors (6). Interestingly, genetic effects were more prominent in men than in women. Twin research from the United States has shown that genetics has important effects on meal size and meal frequency (7, 8). Two recent US studies assessed eating behavior by using the Three-Factor Eating Questionnaire (TFEQ) (9), which is a widely used self-assessment instrument that measures 3 domains: cognitive restraint, hunger, and disinhibition. A family study, which included 624 Amish men and women, estimated the heritability of restraint, disinhibition, and hunger to be 28%, 40%, and 23%, respectively (10). A second study, wh