title: Effects of Dietary Protein and Fiber at Breakfast on Appetite, ad Libitum Energy Intake at Lunch, and Neural Responses to Visual Food Stimuli in Overweight Adults.
abstract: Increasing either protein or fiber at mealtimes has relatively modest effects on ingestive behavior. Whether protein and fiber have additive or interactive effects on ingestive behavior is not known. Fifteen overweight adults (5 female, 10 male; BMI: 27.1 ± 0.2 kg/m²; aged 26 ± 1 year) consumed four breakfast meals in a randomized crossover manner (normal protein (12 g) + normal fiber (2 g), normal protein (12 g) + high fiber (8 g), high protein (25 g) + normal fiber (2 g), high protein (25 g) + high fiber (8 g)). The amount of protein and fiber consumed at breakfast did not influence postprandial appetite or ad libitum energy intake at lunch. In the fasting-state, visual food stimuli elicited significant responses in the bilateral insula and amygdala and left orbitofrontal cortex. Contrary to our hypotheses, postprandial right insula responses were lower after consuming normal protein vs. high protein breakfasts. Postprandial responses in other a priori brain regions were not significantly influenced by protein or fiber intake at breakfast. In conclusion, these data do not support increasing dietary protein and fiber at breakfast as effective strategies for modulating neural reward processing and acute ingestive behavior in overweight adults.
authors.affiliation: Department of Nutrition Science, Purdue University, West Lafayette, IN 47907, USA. sayer@purdue.edu.
authors.forename: R Drew
authors.initials: RD
authors.lastname: Sayer
authors.affiliation: Department of Nutrition Science, Purdue University, West Lafayette, IN 47907, USA. aboaten@purdue.edu.
authors.forename: Akua F
authors.initials: AF
authors.lastname: Amankwaah
authors.affiliation: Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA. gtamer@purdue.edu.
authors.forename: Gregory G
authors.initials: GG
authors.lastname: Tamer
authors.affiliation: Department of Statistics, Purdue University, West Lafayette, IN 47907, USA. chen929@purdue.edu.
authors.forename: Ningning
authors.initials: N
authors.lastname: Chen
authors.affiliation: Department of Nutrition Science, Purdue University, West Lafayette, IN 47907, USA. amyjwright2@purdue.edu.
authors.forename: Amy J
authors.initials: AJ
authors.lastname: Wright
authors.affiliation: Department of Psychiatry, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, CO 80045, USA. Jason.Tregellas@ucdenver.edu.
authors.forename: Jason R
authors.initials: JR
authors.lastname: Tregellas
authors.affiliation: Department of Medicine, Division of Endocrinology, Metabolism and Diabetes, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, CO 80045, USA. Marc.Cornier@ucdenver.edu.
authors.forename: Marc-Andre
authors.initials: MA
authors.lastname: Cornier
authors.affiliation: Department of Neurology, Indiana University School of Medicine, Indianapolis, IN 46202, USA. dkareken@iu.edu.
authors.forename: David A
authors.initials: DA
authors.lastname: Kareken
authors.affiliation: Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA. tmt@purdue.edu.
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Talavage
authors.affiliation: Department of Nutrition, Georgia State University, Atlanta, GA 30303, USA. mmccrory@gsu.edu.
authors.forename: Megan A
authors.initials: MA
authors.lastname: McCrory
authors.affiliation: Department of Nutrition Science, Purdue University, West Lafayette, IN 47907, USA. campbellw@purdue.edu.
authors.forename: Wayne W
authors.initials: WW
authors.lastname: Campbell
mesh_terms: D000328:Adult; D000679:Amygdala / Q000503:physiopathology; D001066:Appetite / Q000187:drug effects*; D015992:Body Mass Index; D062408:Breakfast; D002540:Cerebral Cortex / Q000503:physiopathology; D018592:Cross-Over Studies; D004043:Dietary Fiber / Q000008:administration & dosage*; D004044:Dietary Proteins / Q000008:administration & dosage*; D002149:Energy Intake / Q000187:drug effects*; D005215:Fasting / Q000502:physiology; D005247:Feeding Behavior / Q000187:drug effects; D005260:Female; D006801:Humans; D062409:Lunch; D008297:Male; D008875:Middle Aged; D050177:Overweight / Q000178:diet therapy* / Q000503:physiopathology / Q000523:psychology; D010775:Photic Stimulation / Q000379:methods; D019518:Postprandial Period / Q000187:drug effects; D012201:Reward; D055815:Young Adult
chemical_list: D004043:Dietary Fiber; D004044:Dietary Proteins
keywords: appetite regulation; dietary fiber; dietary protein; fMRI; food reward; overweight