title: Olive oil aroma extract modulates cerebral blood flow in gustatory brain areas in humans.
abstract: BACKGROUND
  Low- and high-fat meals affect homeostatic and gustatory brain areas differentially. In a previous study, we showed that a high-fat meal decreased cerebral blood flow (CBF) in homeostatic brain areas (hypothalamus), whereas a low-fat meal increased CBF in gustatory regions (anterior insula).
  
  
  OBJECTIVE
  The aim of this study was to investigate the long-lasting effect of fat-free flavor-active compounds of olive oil on the brain and whether those aroma components can trigger fat-associated brain responses in homeostatic and gustatory regions.
  
  
  METHODS
  Eleven healthy male subjects participated in a functional magnetic resonance imaging study. On 2 measurement days, subjects consumed single-blinded a plain low-fat yogurt or low-fat yogurt mixed with a fat-free aroma extract of olive oil. Resting CBF was measured before and 30 and 120 min after yogurt intake. Hunger was rated before each measurement. Blood samples were collected at 6 time points.
  
  
  RESULTS
  The extract-containing yogurt elicited higher CBF in the frontal operculum 30 and 120 min after a meal. Furthermore, the activity change in the anterior insula after 30 min correlated positively with the glucose change in the extract condition only. No effects were observed in the hypothalamus.
  
  
  CONCLUSIONS
  The anterior insula and the frontal operculum are regarded as the primary taste cortex. Modulation of the frontal operculum by the yogurt containing the olive oil extract suggests that it might be possible to simulate fat-triggered sensations in the brain on the gustatory level, possibly by ingredients the body implicitly associates with fat. This trial was registered at clinicaltrials.gov as NCT01716286.
authors.affiliation: Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany (HP, MAH, RV, SF, and SK); the fMEG Center, University of Tübingen, Tübingen, Germany (HP, MAH, RV, SF, and SK); the Department of Internal Medicine IV, University Hospital Tübingen, Tübingen, Germany (AF, KL, and LF); the Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, Tübingen, Germany (AF, HP, and SK); the German Center for Diabetes Research, Neuherberg, Germany (AF, HP, and SK); the Institute of Food Science and Biotechnology, University of Hohenheim, Stuttgart, Germany (AK and JH); the German Research Center for Food Chemistry, Freising, Germany (PS); and the Department of Nutritional and Physiological Chemistry, University of Vienna, Vienna, Austria (VS).
authors.forename: Sabine
authors.initials: S
authors.lastname: Frank
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Linder
authors.forename: Louise
authors.initials: L
authors.lastname: Fritsche
authors.forename: Maike A
authors.initials: MA
authors.lastname: Hege
authors.forename: Stephanie
authors.initials: S
authors.lastname: Kullmann
authors.forename: Alina
authors.initials: A
authors.lastname: Krzeminski
authors.forename: Andreas
authors.initials: A
authors.lastname: Fritsche
authors.forename: Peter
authors.initials: P
authors.lastname: Schieberle
authors.forename: Veronika
authors.initials: V
authors.lastname: Somoza
authors.forename: Jörg
authors.initials: J
authors.lastname: Hinrichs
authors.forename: Ralf
authors.initials: R
authors.lastname: Veit
authors.forename: Hubert
authors.initials: H
authors.lastname: Preissl
mesh_terms: D000328:Adult; D015992:Body Mass Index; D002540:Cerebral Cortex / Q000187:drug effects* / Q000378:metabolism; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D005625:Frontal Lobe / Q000187:drug effects* / Q000378:metabolism; D006706:Homeostasis / Q000187:drug effects / Q000502:physiology; D006801:Humans; D006815:Hunger / Q000187:drug effects / Q000502:physiology; D007031:Hypothalamus / Q000187:drug effects / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D008297:Male; D009812:Odorants; D000069463:Olive Oil; D010296:Parietal Lobe; D010936:Plant Extracts / Q000494:pharmacology; D010938:Plant Oils / Q000494:pharmacology*; D016037:Single-Blind Method; D013649:Taste / Q000502:physiology; D015014:Yogurt
chemical_list: D000069463:Olive Oil; D010936:Plant Extracts; D010938:Plant Oils