Fig. 4: Perceptions of appetite and gastrointestinal symptoms.

Mean±standard error of mean (SEM) visual analogue scores (VAS; mm; 0–180min) of fullness (a, b), hunger (c, d), desire to eat (e, f), prospective food consumption (g, h), nausea (I, j) and bloating (k, l) in younger (n=10) and older (n = 10) men immediately before and after drinks containing water (control) and 30 g whey protein. Time (0–180min) effects were determined by using mixed effects analysis. Ratings of fullness, hunger, nausea, and bloating did not change from baseline during all study days in both age groups (P > 0.05). Scores for prospective food consumption were significantly higher in the young on the control day (P = 0.040), whereas in the older group, scores were significantly higher on the protein day (protein effect P = 0.004; age x protein interaction effect P = 0.001). For desire to eat prospective consumption was significantly higher in the younger than older group on the control day (age effect P = 0.040), but not on the protein day (age effect P = 0.98; age×protein interaction effect P = 0.020).