Mette Schmedes1, Line Q Bendtsen2, Sisse Gomes2, Bjørn Liaset3, Jens J Holst4, Christian Ritz2, Søren Reitelseder5, Anders Sjödin2, Arne Astrup2, Jette F Young1, Ulrik K Sundekilde1, Hanne C Bertram1. 1. Department of Food Science, Aarhus University, Aarslev, Denmark. 2. Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark. 3. Department of Seafood in Model Systems, Institute of Marine Research, Bergen, Norway. 4. Department of Biomedical Sciences, The NNF Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark. 5. Department of Biomedical Sciences, Institute of Sports Medicine, Bispebjerg Hospital, Copenhagen, Denmark.
Abstract
BACKGROUND:Casein and whey proteins differ in amino acid composition and absorption rate; however, the absorption rate of casein can be increased to mimic that of whey proteins by exogenous hydrolysis. In view of these compositional differences, we studied the metabolic responses to intake of casein, hydrolyzed casein, and whey proteins in overweight and moderately obese men and women by investigating select urinary and blood plasma metabolites. RESULTS: A total of 21 urinary and 23 plasma metabolites were identified by nuclear magnetic resonance spectroscopy. The postprandial plasma metabolites revealed a significant diet-time interaction for isoleucine (P = 0.001) and tyrosine (P = 0.001). The level of isoleucine and tyrosine peaked 90 min postprandially with a 1.4-fold difference following intake of whey proteins compared with either casein or hydrolyzed casein. A 1.2-fold higher urinary level of lactate was observed after intake of whey proteins compared with intake of intact casein (P < 0.01). CONCLUSION: The plasma metabolites revealed different amino acid profiles reflecting the amino acid composition of casein and whey proteins. Furthermore, the results support that casein hydrolysates neither affect the postprandial amino acid absorption rate nor the amino acid level compared with that of intact casein. The urinary lactate increases following whey protein intake might indicate a higher metabolism of glucogenic amino acids.
RCT Entities:
BACKGROUND: Casein and whey proteins differ in amino acid composition and absorption rate; however, the absorption rate of casein can be increased to mimic that of whey proteins by exogenous hydrolysis. In view of these compositional differences, we studied the metabolic responses to intake of casein, hydrolyzed casein, and whey proteins in overweight and moderately obesemen and women by investigating select urinary and blood plasma metabolites. RESULTS: A total of 21 urinary and 23 plasma metabolites were identified by nuclear magnetic resonance spectroscopy. The postprandial plasma metabolites revealed a significant diet-time interaction for isoleucine (P = 0.001) and tyrosine (P = 0.001). The level of isoleucine and tyrosine peaked 90 min postprandially with a 1.4-fold difference following intake of whey proteins compared with either casein or hydrolyzed casein. A 1.2-fold higher urinary level of lactate was observed after intake of whey proteins compared with intake of intact casein (P < 0.01). CONCLUSION: The plasma metabolites revealed different amino acid profiles reflecting the amino acid composition of casein and whey proteins. Furthermore, the results support that casein hydrolysates neither affect the postprandial amino acid absorption rate nor the amino acid level compared with that of intact casein. The urinary lactate increases following whey protein intake might indicate a higher metabolism of glucogenic amino acids.
Authors: Hanna Fjeldheim Dale; Caroline Jensen; Trygve Hausken; Einar Lied; Jan Gunnar Hatlebakk; Ingeborg Brønstad; Dag Arne Lihaug Hoff; Gülen Arslan Lied Journal: J Nutr Sci Date: 2018-11-28
Authors: Hanna Fjeldheim Dale; Caroline Jensen; Trygve Hausken; Einar Lied; Jan Gunnar Hatlebakk; Ingeborg Brønstad; Dag Arne Lihaug Hoff; Gülen Arslan Lied Journal: Food Nutr Res Date: 2019-10-22 Impact factor: 3.894