Effect of premeal consumption of whey protein and its hydrolysate on food intake and postmeal glycemia and insulin responses in young adults

• Published in: The American journal of clinical nutrition Vol. 91; no. 4; pp. 966 - 975
• Main Authors: Akhavan, Tina, Luhovyy, Bohdan L, Brown, Peter H, Cho, Clara E, Anderson, G. Harvey
• Format: Journal Article
• Language: English
• Published: Bethesda, MD American Society for Clinical Nutrition 01.04.2010; American Society for Nutrition; American Society for Clinical Nutrition, Inc
• Subjects: administration & dosage; Adult; Area Under Curve; Biological and medical sciences; blood; blood glucose; Blood Glucose - metabolism; Carbohydrates; Cross-Over Studies; Dairy products; Diet; Dietary Proteins; Dietary Proteins - administration & dosage; dosage; Dose-Response Relationship, Drug; drug effects; Energy Intake; Energy Intake - drug effects; Feeding. Feeding behavior; Female; food intake; Fundamental and applied biological sciences. Psychology; Glucose; glycemic effect; Humans; Hydrolysis; Insulin; Insulin - blood; insulin secretion; Male; meals (menu); metabolism; Milk Proteins; Milk Proteins - pharmacology; Nutrition; pharmacology; Postprandial Period; postprandial state; protein hydrolysates; protein supplements; Proteins; satiety; Satiety Response; Satiety Response - drug effects; temporal variation; Vertebrates: anatomy and physiology, studies on body, several organs or systems; whey protein; Whey Proteins; Young Adult; Young adults; Human; Pancreatic hormone; Hydrolysate; Food intake; Young adult; Whey protein; Insulin; Glycemia
• ISSN: 0002-9165; 1938-3207; 1938-3207
• DOI: 10.3945/ajcn.2009.28406

BACKGROUND: Dairy protein ingestion before a meal reduces food intake and, when consumed with carbohydrate, reduces blood glucose. OBJECTIVE: The objective was to describe the effect of whey protein (WP) or its hydrolysate (WPH) when consumed before a meal on food intake, pre- and postmeal satiety, and concentrations of blood glucose and insulin in healthy young adults. DESIGN: Two randomized crossover studies were conducted. WP (10-40 g) in 300 mL water was provided in experiment 1, and WP (5-40 g) and WPH (10 g) in 300 mL water were provided in experiment 2. At 30 min after consumption, the subjects were fed an ad libitum pizza meal (experiment 1) or a preset pizza meal (12 kcal/kg, experiment 2). Satiety, blood glucose, and insulin were measured at baseline and at intervals both before and after the meals. RESULTS: In experiment 1, 20-40 g WP suppressed food intake (P < 0.0001) and 10-40 g WP reduced postmeal blood glucose concentrations and the area under the curve (AUC) (P < 0.05). In experiment 2, 10-40 g WP, but not WPH, reduced postmeal blood glucose AUC and insulin AUC in a dose-dependent manner (P < 0.05). The ratio of cumulative blood glucose to insulin AUCs (0-170 min) was reduced by ≥10 g WP but not by 10 g WPH. CONCLUSIONS: WP consumed before a meal reduces food intake, postmeal blood glucose and insulin, and the ratio of cumulative blood glucose to insulin AUCs in a dose-dependent manner. Intact WP, but not WPH, contributes to blood glucose control by both insulin-dependent and insulin-independent mechanisms. This trial was registered at clinicaltrials.gov as NCT00988377 and NCT00988182.