Fig. 2: Mean ± standard error of mean (SEM) antral area (%) in younger (n = 10) and older (n = 10) men after drinks containing water (control) and 30 g whey protein.

Main age and protein effects and age x protein interaction effect were determined by using mixed effects analysis. Gastric emptying (antral area) of the protein drink was slower than control to a similar degree in both the age groups. The main effect of protein for 50% gastric emptying time (T50 min; P = 0.001) was significant; the age (P = 0.93) and the age × protein interaction (P = 0.13) effects were not significant.