title: Glycemia and insulinemia in healthy subjects after lactose-equivalent meals of milk and other food proteins: the role of plasma amino acids and incretins.
abstract: BACKGROUND
  Milk products deviate from other carbohydrate-containing foods in that they produce high insulin responses, despite their low GI. The insulinotropic mechanism of milk has not been elucidated.
  
  
  OBJECTIVE
  The objective was to evaluate the effect of common dietary sources of animal or vegetable proteins on concentrations of postprandial blood glucose, insulin, amino acids, and incretin hormones [glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1] in healthy subjects.
  
  
  METHODS
  Twelve healthy volunteers were served test meals consisting of reconstituted milk, cheese, whey, cod, and wheat gluten with equivalent amounts of lactose. An equicarbohydrate load of white-wheat bread was used as a reference meal.
  
  
  RESULTS
  A correlation was found between postprandial insulin responses and early increments in plasma amino acids; the strongest correlations were seen for leucine, valine, lysine, and isoleucine. A correlation was also obtained between responses of insulin and GIP concentrations. Reconstituted milk powder and whey had substantially lower postprandial glucose areas under the curve (AUCs) than did the bread reference (-62% and -57%, respectively). Whey meal was accompanied by higher AUCs for insulin (90%) and GIP (54%).
  
  
  CONCLUSIONS
  It can be concluded that food proteins differ in their capacity to stimulate insulin release, possibly by differently affecting the early release of incretin hormones and insulinotropic amino acids. Milk proteins have insulinotropic properties; the whey fraction contains the predominating insulin secretagogue.
authors.affiliation: Department of Applied Nutrition and Food Chemistry, Lund University, Sweden. mikael.nilsson@inl.lth.se
authors.forename: Mikael
authors.initials: M
authors.lastname: Nilsson
authors.forename: Marianne
authors.initials: M
authors.lastname: Stenberg
authors.forename: Anders H
authors.initials: AH
authors.lastname: Frid
authors.forename: Jens J
authors.initials: JJ
authors.lastname: Holst
authors.forename: Inger M E
authors.initials: IM
authors.lastname: Björck
mesh_terms: D000328:Adult; D000596:Amino Acids / Q000097:blood*; D019540:Area Under Curve; D001786:Blood Glucose / Q000187:drug effects*; D004032:Diet; D005260:Female; D038321:Glycemic Index; D006801:Humans; D007328:Insulin / Q000097:blood*; D008297:Male; D008894:Milk Proteins / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000494:pharmacology*; D019518:Postprandial Period
chemical_list: D000596:Amino Acids; D001786:Blood Glucose; D007328:Insulin; D008894:Milk Proteins