Whey Protein Reduces Glucose, Insulin

CHICAGOA study published in the American Journal of Clinical Nutrition found whey protein consumed before a meal reduced food intake, post-meal blood glucose and insulin; and the ratio of cumulative blood glucose to insulin area under the curve (AUC) in a dose-dependent manner (2010;91:966-975). Two randomized crossover studies were conducted. Whey protein (10 g to 40 g) in 300 mL of water was provided in experiment one, and whey protein (5 g to 40 g) and whey protein hydrolysate (WPH; 10 g) in 300 mL of water were provided in experiment two. At 30 minutes after consumption, the subjects were fed an ad libitum pizza meal (experiment one) or a preset pizza meal (12 kcal/kg, experiment two).

In experiment one, 20 g to 40 g of whey protein suppressed food intake (P<0.0001) and 10 g to 40 g of whey protein reduced post-meal blood glucose concentrations and the AUC (P<0.05). In experiment two, 10 g to 40 g of whey protein, but not WPH, reduced post-meal blood glucose AUC and insulin AUC in a dose-dependent manner (P<0.05). The ratio of cumulative blood glucose to insulin AUCs (0 to 170 minutes) was reduced by 10 g of whey protein but not by 10 g of WPH. Intact whey protein, but not WPH, contributed to blood glucose control by both insulin-dependent and insulin-independent mechanisms.