title: Self-comparisons as motivators for healthy behavior.
abstract: OBJECTIVE
  We explored whether individuals' comparison of themselves to their social contacts, specifically feeling fitter or thinner than friends, is a significant predictor of three weight-loss behaviors (dieting, reducing alcohol, exercising).
  
  
  METHODS
  We used a longitudinal survey of a national sample of Americans (N = 20,373) to measure respondents' personal social networks and their self-comparisons to their social contacts at two annual waves.
  
  
  RESULTS
  Participants who felt thinner than friends in Wave 1 had 1.16 lower odds of dieting in Wave 2. Those who felt fitter than friends in Wave 1 had 1.10 times higher odds of reducing alcohol and 1.18 times higher odds of exercising in Wave 2. We found that 20% of the relationship between feeling thin at baseline and subsequent dieting may be because feeling heavier than friends makes one want to lose weight. This same dynamic accounts for 25% of the relationship between feeling fit and dieting and 12% of the relationship between feeling thin and reducing alcohol.
  
  
  CONCLUSIONS
  These results suggest that normative self-comparison with important others is a potentially salient determinant of obesity-related health behavior and appears to work differently depending upon the behavior. Interventions may benefit from exploiting social comparisons in targeted ways.
authors.affiliation: Family Medicine and Public Health, School of Medicine, University of California San Diego, San Diego, California, USA.
authors.forename: Holly B
authors.initials: HB
authors.lastname: Shakya
authors.affiliation: Department of Sociology, Yale University, New Haven, Connecticut, USA.
authors.forename: Nicholas A
authors.initials: NA
authors.lastname: Christakis
authors.affiliation: Family Medicine and Public Health, School of Medicine, University of California San Diego, San Diego, California, USA.|Department of Political Science, University of California San Diego, San Diego, California, USA.
authors.forename: James H
authors.initials: JH
authors.lastname: Fowler
mesh_terms: D000368:Aged; D001835:Body Weight; D015444:Exercise / Q000523:psychology; D005247:Feeding Behavior / Q000523:psychology; D005260:Female; D033062:Friends / Q000523:psychology; D015438:Health Behavior; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009042:Motivation; D009765:Obesity / Q000523:psychology; D000067074:Peer Influence; D012649:Self Concept; D012919:Social Behavior; D011795:Surveys and Questionnaires; D014481:United States