Co-ingestion of NUTRALYS® pea protein and a high-carbohydrate beverage influences the glycaemic, insulinaemic, glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) responses: preliminary results of a randomised controlled trial.

Abstract

Plant-based proteins may have the potential to improve glycaemic and gastrointestinal hormone responses to foods and beverages. The aim of this study was to investigate the effect of two doses of pea protein on postprandial glycaemic, insulinaemic, glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) response following a high-carbohydrate beverage intake in healthy individuals. In a single-blind, randomised, controlled, repeat measure, crossover design trial, thirty-one participants were randomly assigned to ingest 50g glucose (Control), 50g glucose with 25g pea protein (Test 1) and 50g glucose with 50g pea protein (Test 2) on three separate days. Capillary blood samples (blood glucose and plasma insulin measurements) and venous blood samples (GIP and GLP-1 concentrations) were taken before each test and at fixed intervals for 180min. The data were compared using repeated-measures ANOVA or the Friedman test. Glucose incremental Area under the Curve (iAUC180) was significantly lower (p < 0.001) after Test 2 compared with Control (- 53%), after Test 1 compared with Control (- 31%) and after Test 2 compared with Test 1 (-32%). Insulin iAUC 180 was significantly higher (p < 0.001) for Test 1 (+ 28%) and Test 2 (+ 40%) compared with Control and for Test 2 (+ 17%) compared with Test 1 (p = 0.003). GIP and GLP-1 release showed no clear difference between Control and Pea protein drinks. The consumption of pea protein reduced postprandial glycaemia and stimulated insulin release in healthy adults with a dose-response effect, supporting its role in regulating glycaemic and insulinaemic responses.