title: Genetic and environmental influences on eating patterns of twins aged >/=50 y.
abstract: BACKGROUND
  Clinicians and researchers could benefit from a greater understanding of the role of genetic and environmental factors in human eating behavior.
  
  
  OBJECTIVE
  Our aim was to estimate the relative influence of genetic and environmental factors on habitual eating patterns in middle-aged and elderly men and women.
  
  
  METHODS
  Male and female twins (n = 4640) aged >/=50 y completed a mailed version of the National Cancer Institute food-frequency questionnaire. Factor analysis was performed to identify eating patterns among respondents. Estimates of genetic, common environmental (shared by family members), and specific environmental (unique to an individual) influences were obtained for food use, serving size, and consumption frequency by comparing monozygotic and dizygotic twin-pair groups with structural equation analysis.
  
  
  RESULTS
  Two independent eating patterns were identified: the first consisted of items high in fat, salt, and sugar, and the second reflected healthful eating habits. Although the influence of environmental factors was larger, between 15% and 38% of the total variation in pattern 1 and between 33% and 40% in pattern 2 were explained by genetic influences. Models accounting for sex differences in genetic and environmental estimates fit the data significantly better for food use and serving size of foods in eating pattern 1 and for food use in eating pattern 2.
  
  
  CONCLUSIONS
  Although 60-85% of the variability in eating patterns was associated with environmental factors, genetic influences were also apparent and there was some evidence of sex specificity. These findings may be important in crafting dietary interventions and predicting adherence to these interventions.
authors.affiliation: Virginia Institute for Psychiatric and Behavioral Genetics, Virginia Commonwealth University, Richmond, USA. mvandenb@intra.nida.nih.gov
authors.forename: M B
authors.initials: MB
authors.lastname: van den Bree
authors.forename: L J
authors.initials: LJ
authors.lastname: Eaves
authors.forename: J T
authors.initials: JT
authors.lastname: Dwyer
mesh_terms: D000368:Aged; D004034:Diet Surveys; D004435:Eating / Q000235:genetics* / Q000502:physiology / Q000523:psychology; D004522:Educational Status; D004651:Employment; D005163:Factor Analysis, Statistical; D005247:Feeding Behavior / Q000502:physiology / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D017533:Marital Status; D008875:Middle Aged; D008954:Models, Biological; D012737:Sex Factors; D012923:Social Class; D012931:Social Environment; D011795:Surveys and Questionnaires; D014429:Twins, Dizygotic; D014430:Twins, Monozygotic