title: Relative ability of fat and sugar tastes to activate reward, gustatory, and somatosensory regions.
abstract: BACKGROUND
  Although the intake of high-fat and high-sugar food activates mesolimbic reward, gustatory, and oral somatosensory brain regions, contributing to overeating, few studies have examined the relative role of fat and sugar in the activation of these brain regions, which would inform policy, prevention, and treatment interventions designed to reduce obesity.
  
  
  OBJECTIVE
  We evaluated the effect of a high-fat or high-sugar equicaloric chocolate milkshake and increasing fat or sugar milkshake content on the activation of these regions.
  
  
  METHODS
  Functional magnetic resonance imaging was used to assess the neural response to the intake of high-fat/high-sugar, high-fat/low-sugar, low-fat/high-sugar, and low-fat/low-sugar chocolate milkshakes and a tasteless solution in 106 lean adolescents (mean ± SD age = 15.00 ± 0.88 y). Analyses contrasted the activation to the various milkshakes.
  
  
  RESULTS
  High-fat compared with high-sugar equicaloric milkshakes caused greater activation in the bilateral caudate, postcentral gyrus, hippocampus, and inferior frontal gyrus. High-sugar compared with high-fat equicaloric milkshakes caused greater activation in the bilateral insula extending into the putamen, the Rolandic operculum, and thalamus, which produced large activation regions. Increasing sugar in low-fat milkshakes caused greater activation in the bilateral insula and Rolandic operculum; increasing fat content did not elicit greater activation in any region.
  
  
  CONCLUSIONS
  Fat caused greater activation of the caudate and oral somatosensory regions than did sugar, sugar caused greater activation in the putamen and gustatory regions than did fat, increasing sugar caused greater activity in gustatory regions, and increasing fat did not affect the activation. Results imply that sugar more effectively recruits reward and gustatory regions, suggesting that policy, prevention, and treatment interventions should prioritize reductions in sugar intake. This trial was registered at clinicaltrials.gov as DK092468.
authors.affiliation: Oregon Research Institute, Eugene, OR.
authors.forename: Eric
authors.initials: E
authors.lastname: Stice
authors.forename: Kyle S
authors.initials: KS
authors.lastname: Burger
authors.forename: Sonja
authors.initials: S
authors.lastname: Yokum
mesh_terms: D000293:Adolescent; D001628:Beverages / Q000032:analysis; D001931:Brain Mapping; D002421:Caudate Nucleus / Q000378:metabolism*; D003611:Dairy Products / Q000032:analysis; D004041:Dietary Fats / Q000378:metabolism*; D019422:Dietary Sucrose / Q000378:metabolism*; D005260:Female; D006624:Hippocampus / Q000378:metabolism*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009474:Neurons / Q000378:metabolism*; D009922:Oregon; D012201:Reward; D012677:Sensation; D013003:Somatosensory Cortex / Q000378:metabolism*; D013649:Taste; D055697:Taste Perception
chemical_list: D004041:Dietary Fats; D019422:Dietary Sucrose