title: Sensitization of food reinforcement is related to weight status and baseline food reinforcement.
abstract: BACKGROUND
  Food reinforcement is an empirical index of motivation to obtain food. Higher levels of food reinforcement are associated with increased energy intake and increased body weight. Food reinforcement can vary over repeated food presentations, as people may show reduced reinforcing value if they satiate to repeated reinforcers, or they may show sensitization, or an increase in reinforcing value with repeated presentations. Over the past few years, our laboratory has been studying the impact of repeated administration of large portions of high energy density snack foods on food reinforcement. We have shown in three separate studies that the majority of non-obese individuals become satiated after 2 weeks of the same snack food administration, but that a subset of obese individuals sensitize after this same manipulation.
  
  
  OBJECTIVE
  The purpose of the study presented here was to identify predictors of reinforcer satiation or sensitization.
  
  
  METHODS
  For the analyses presented here, we combined data sets from three previous studies for a total of 67 adult participants.
  
  
  RESULTS
  We found that higher body mass index (BMI) and higher baseline motivation to eat predicted sensitization, and baseline motivation to eat moderated the effects of BMI, such that higher baseline responding for food predicted sensitization in obese individuals, but satiation in non-obese individuals.
  
  
  CONCLUSIONS
  These data suggest that repeated exposure to high energy density snack foods may result in sensitization to those foods, with similar effects as drugs of abuse in susceptible individuals, and that an individual's BMI and baseline responding act as predictors of this response.
authors: Department of Exercise and Nutrition Sciences, School of Public Health and Health Professions, University at Buffalo, Buffalo, NY 14214, USA. jltemple@buffalo.edu
authors: J L
authors: JL
authors: Temple
authors: L H
authors: LH
authors: Epstein
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D015992:Body Mass Index; D059305:Diet, High-Fat; D004435:Eating / Q000523:psychology*; D002149:Energy Intake; D005247:Feeding Behavior; D005260:Female; D005518:Food Preferences / Q000523:psychology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009042:Motivation / Q000502:physiology; D009765:Obesity / Q000523:psychology*; D012054:Reinforcement, Psychology; D012527:Satiation / Q000502:physiology*; D013851:Thinness / Q000523:psychology*; D055815:Young Adult