title: Factors influencing the reinforcing value of fruit and unhealthy snacks.
abstract: OBJECTIVE
  The present study investigated the reinforcing value of healthy and unhealthy snack food in adolescents (n = 108, aged 14-16 years). Moderation by access to different foods, sex and the personality trait reward sensitivity is tested.
  
  
  METHODS
  In a computerized Food Reinforcement Task, adolescents could earn portions of a healthy and an unhealthy snack following an identical progressive reinforcement schedule for both food types. Reinforcing value of food was indexed by the number of button presses for each food type. Participants were allocated randomly to two-order condition: fruit-snack versus snack-fruit. Reward sensitivity was assessed with the Dutch age-downward version of Carver and White's BIS/BAS scale.
  
  
  RESULTS
  Results showed that the reinforcing value of an unhealthy snack is higher than that of fruit, with participants making more button presses for unhealthy snacks, M = 1280.40, SD = 1203.53, than for fruit, M = 488.04, SD = 401.45, F(1,48) = 25.37, p < 0.001. This effect is stronger in boys (β = -1367.67) than in girls (β = -548.61). The effect is only present in the snack-fruit condition, not in the fruit-snack condition, indicating that access to food moderates the effect of food type. There is no evidence for moderation by reward sensitivity.
  
  
  CONCLUSIONS
  Results point to the importance of simultaneously increasing barriers to obtain unhealthy food and promoting access to healthy food in order to facilitate healthy food choices.
authors: Department of Developmental, Personality and Social Psychology, Ghent University, H. Dunantlaan 2, 9000, Ghent, Belgium. Leentje.Vervoort@ugent.be.
authors: L
authors: http://orcid.org/0000-0002-5082-7175
authors: L
authors: Vervoort
authors: Department of Experimental Clinical and Health Psychology, Ghent University, H. Dunantlaan 2, 9000, Ghent, Belgium.
authors: A
authors: A
authors: Clauwaert
authors: Department of Developmental, Personality and Social Psychology, Ghent University, H. Dunantlaan 2, 9000, Ghent, Belgium.
authors: L
authors: L
authors: Vandeweghe
authors: Leuven School for Mass Communication Research, KU Leuven, Parkstraat 45, 3000, Louvain, Belgium.
authors: J
authors: J
authors: Vangeel
authors: Department of Public Health, Ghent University, De Pintelaan 185, 9000, Ghent, Belgium.
authors: W
authors: W
authors: Van Lippevelde
authors: Department of Developmental, Personality and Social Psychology, Ghent University, H. Dunantlaan 2, 9000, Ghent, Belgium.
authors: L
authors: L
authors: Goossens
authors: Poverty, Health and Nutrition Division, International Food Policy Research Institute, 2033 K St, NW, Washington, DC, 20006-1002, USA.
authors: L
authors: L
authors: Huybregts
authors: Department of Food Safety and Food Quality, Ghent University, Coupure Links 653, 9000, Ghent, Belgium.
authors: C
authors: C
authors: Lachat
authors: Leuven School for Mass Communication Research, KU Leuven, Parkstraat 45, 3000, Louvain, Belgium.
authors: S
authors: S
authors: Eggermont
authors: Leuven School for Mass Communication Research, KU Leuven, Parkstraat 45, 3000, Louvain, Belgium.|Research Foundation Flanders (FWO), Egmontstraat 5, 1000, Brussels, Belgium.
authors: K
authors: K
authors: Beullens
authors: Department of Developmental, Personality and Social Psychology, Ghent University, H. Dunantlaan 2, 9000, Ghent, Belgium.
authors: C
authors: C
authors: Braet
authors: Department of Food Safety and Food Quality, Ghent University, Coupure Links 653, 9000, Ghent, Belgium.
authors: N
authors: N
authors: De Cock
mesh_terms: D000293:Adolescent; D015992:Body Mass Index; D002755:Choice Behavior; D004032:Diet; D000072001:Diet, Healthy; D005260:Female; D005518:Food Preferences; D005638:Fruit; D006801:Humans; D008297:Male; D009042:Motivation; D012054:Reinforcement, Psychology; D012737:Sex Factors; D062410:Snacks; D011795:Surveys and Questionnaires; D013649:Taste
keywords: Adolescents; Food reward; Reinforcing value of food; Reward sensitivity