Giezenaar C, et al. – This research intended to ascertain the effect of the timing of whey protein ingestion on appetite and subsequent ad libitum energy intake in healthy older men.The ingestion of 30 g protein increased total energy intake, regardless of the time of intake in association with the meal. Hence, the utility of “pure” whey protein drinks was supported, to increase the overall protein and energy intake in older adults, at risk of undernutrition.

Methods

• The design of this research was a single blind, randomized study.
• 16 older men were examined on 5 occasions, on which they consumed a whey protein drink (30 g/120 kcal, 140 mL) 3, 2, 1 hour(s), or immediately before a buffet meal, from which ad libitum energy intake was quantified, and isopalatable noncaloric drinks (∼1 kcal) at the remaining time points.
• Noncaloric drinks were ingested at all time points, on the control day.
• Perceptions of appetite and gastrointestinal symptoms were identified, by visual analog scales, throughout the study days.

Results

• No effect was observed of the timing of protein ingestion on perceptions of appetite and gastrointestinal symptoms (P > .05) or energy intake at the buffet meal (3 hours: 888 ± 49 kcal, 2 hours: 879 ± 56 kcal, 1 hours: 909 ± 47 kcal, 0 hour: 892 ± 51 kcal, control: 930 ± 49 kcal, P = .94).
• Total energy intake (ie, preload + test meal) appeared to be higher on the protein days compared with control (82 ± 24 kcal increase, P = .003).