Insulin‐Independent Mechanisms of Action of Pre‐Meal Consumption of Whey Protein on Post‐meal Glycemic Response in Healthy Adults

Whey protein (WP) when consumed prior to a meal reduces post‐meal glycemic response (Akhavan et al, AJCN, 2010). The objective of the study was to identify insulin‐independent mechanisms of action. Healthy men received, in a randomized order, WP and glucose preloads (10 and 20 g/300 mL) and water control with paracetamol (1.5 g). At 30 min after consumption, the subjects were fed a preset pizza meal (12 kcal/ kg). Plasma concentrations of paracetamol, glucose and incretin hormones, involved in glycemic control, were measured at pre‐ (0–30) and post‐ (50–230 min) meal. Pre‐meal plasma paracetamol concentrations were reduced by WP, indicating delayed gastric emptying. Consumption of WP and glucose similarly reduced post‐meal plasma glucose but insulin was increased only after glucose preloads (p < 0.001). Associated with the lower post‐meal glycemic responses after WP were lower C‐peptide and higher GLP‐1, PYY and ghrelin (all p < 0.001), but similar amylin and GIP than after glucose preloads. These responses support the hypothesis the glycemic control after WP occurs in part by noninsulin dependent mechanisms. Thus, pre‐meal consumption of WP may be a novel strategy, comparable to pharmacological therapy e.g. sulphonylureas, for the prevention and treatment of hyperglycemia and type 2 diabetes. Grant Funding Source : Supported by Natural Sciences and Engineering Research Council of Canada‐Collaborative Research and Development and Kraft Canada Inc