title: Effects of complete whey-protein breakfasts versus whey without GMP-breakfasts on energy intake and satiety.
abstract: OBJECTIVE
  To compare the effects of whey versus whey without glycomacropeptide (GMP) in a high and a normal amount of protein in a breakfast custard on satiety and energy intake (EI), taking concentrations of amino acids (AA), glucose, insulin, glucagon-like peptide 1 (GLP-1) and ghrelin into account.
  
  
  METHODS
  Twenty-five healthy subjects (mean+/-S.E.M., BMI: 23.9+/-0.3 kg/m(2); age: 22+/-1 years) received a breakfast containing whey or whey without GMP as protein type with 10/55/35 or 25/55/20 En% protein/carbohydrate/fat in a randomized, single-blind design. Appetite profile (Visual Analogue Scale, VAS), glucose, insulin, GLP-1, ghrelin and AA concentrations were measured, and the adequate moment for ad libitum lunch was determined based on differences in ghrelin concentration. In a second set of experiments subjects received the same breakfasts; ad libitum lunch was offered at the pre-determined moment.
  
  
  RESULTS
  After a breakfast with 25 En% protein increases in insulin and GLP-1 and decreases in ghrelin concentrations were larger; increases in satiety ratings were lower than after 10 En% (p<0.05); there was a treatment x time interaction effect on glucose and insulin concentrations (p<0.001). After a breakfast with whey without GMP insulin concentrations were increased more than after whey (p<0.05). EI at lunch was lower after whey than after whey without GMP (2877+/-165 kJ versus 3208+/-178 kJ, p<0.05), coinciding with more increased concentrations of serine, threonine, alanine, alpha-aminobutyric acid and isoleucine (p<0.05).
  
  
  CONCLUSIONS
  GMP as a whey-fraction reduced energy intake coinciding with increased concentrations of certain amino acids, irrespective of the concentration of whey-protein. Although between different concentrations of whey-protein differences in hormone responses were observed, these were unrelated to satiety ratings or energy intake.
authors.affiliation: Dept. of Human Biology, Nutrition and Toxicology Research Institute Maastricht, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands. m.veldhorst@hb.unimaas.nl
authors.forename: Margriet A B
authors.initials: MA
authors.lastname: Veldhorst
authors.forename: Arie G
authors.initials: AG
authors.lastname: Nieuwenhuizen
authors.forename: Ananda
authors.initials: A
authors.lastname: Hochstenbach-Waelen
authors.forename: Klaas R
authors.initials: KR
authors.lastname: Westerterp
authors.forename: Marielle P K J
authors.initials: MP
authors.lastname: Engelen
authors.forename: Robert-Jan M
authors.initials: RJ
authors.lastname: Brummer
authors.forename: Nicolaas E P
authors.initials: NE
authors.lastname: Deutz
authors.forename: Margriet S
authors.initials: MS
authors.lastname: Westerterp-Plantenga
mesh_terms: D000596:Amino Acids / Q000032:analysis; D001066:Appetite; D001786:Blood Glucose / Q000032:analysis; D004044:Dietary Proteins / Q000032:analysis; D002149:Energy Intake; D054439:Ghrelin / Q000032:analysis; D006801:Humans; D007328:Insulin / Q000097:blood; D008894:Milk Proteins / Q000032:analysis; D010455:Peptides / Q000032:analysis; D011897:Random Allocation; D012528:Satiety Response; D016037:Single-Blind Method; D000067816:Whey Proteins
chemical_list: D000596:Amino Acids; D001786:Blood Glucose; D004044:Dietary Proteins; D054439:Ghrelin; D007328:Insulin; D008894:Milk Proteins; D010455:Peptides; D000067816:Whey Proteins