The Short-Term Effect of Whey Compared with Pea Protein on Appetite, Food Intake, and Energy Expenditure in Young and Older Men

Abstract

Background Diets higher in protein have been reported to improve age-related changes in body composition via increased energy expenditure, shifts in substrate oxidation (SO), and decreased appetite. However, how protein source (e.g., animal compared with plant protein) affects energy expenditure, appetite, and food intake as we age is unknown. Objectives The objective of this study was to evaluate the effect of protein source as part of a high-protein breakfast on appetite, food intake, energy expenditure, and fat oxidation in young men (YM) compared with older men (OM). Methods This study used a randomized, single-blinded crossover design, with a 1-wk washout period between testing days. Fifteen YM (mean ± SD age: 25.2 ± 2.8 y) and 15 OM (67.7 ± 4.5 y), healthy adults, participated in the study. Participants arrived fasted and consumed an isocaloric, volume-matched, high-protein (40-g) test beverage made with either an animal [whey protein isolate (WPI)] or plant [pea protein isolate (PPI)] protein isolate source. Markers of appetite and energy expenditure were determined at baseline and over 4 h postprandial. Results There was a significant effect of time, age, and protein source on appetite (P < 0.05). There was no effect of protein source on plasma markers of appetite, food intake, energy expenditure, and SO. After controlling for body weight, OM had decreased energy expenditure (P < 0.05) and lower fat oxidation (P < 0.001) compared with YM. Conclusions This study indicates that a high-protein breakfast containing WPI or PPI exerts comparable effects on appetite, energy expenditure, and 24-h energy intake in both young and older healthy adult men. This trial was registered at clinicaltrials.gov as NCT03399812.

Effects of Pea Protein on Satiety, Postprandial Glucose Response and Appetite Hormones: A Literature Review

“…The addition of fibre to pea protein could lower food intake but Hawley et al (2020) showed that the source of protein did not have a significant effect on food intake. There were minimal reported effects on the difference in participants' VAS scores when comparing whey and pea protein.…”

“…Mollard et al found that pea protein alone or the combination of pea protein and hull fibre did not have any effect in increasing satiety since it did not affect food intake of an ad libitum meal [30]. Additionally, Hawley et al demonstrated that the source of protein whether it was from whey or pea, had no significant effect on appetite, food intake, and energy expenditure [31]. Even with reported increased or similar levels of satiety to the control, physiological components were not consistent with satiety hormone levels glucagonlike peptide-1 (GLP-1), cholecystokinin (CCK), and ghrelin [26].…”

“…When findings related to the effects of pea protein isolates on postprandial responses of satiety and appetite and its benefits were investigated, many proved the positive effect of pea protein consumption and decreased food intake [24,[26][27][28]. Nonetheless, out of the 450 participants included in this review, there were inconsistencies in the results with some studies showing that there was no impact on food intake [30] or no difference between other types of protein and levels of satiety [31].…”

Soybean and Other Legume Proteins Exhibit Beneficial Physiological Effects on Metabolic Syndrome and Inflammatory-Related Disorders

“…Pea protein is an excellent source of BCAAs and has high and balanced contents of leucine, isoleucine and valine. Indeed, there are reports that pea protein is as useful as whey protein in sports nutrition (Table 4) [100][101][102][103].…”

Comparative Assessment of the Acute Effects of Whey, Rice and Potato Protein Isolate Intake on Markers of Glycaemic Regulation and Appetite in Healthy Males Using a Randomised Study Design

“…To date, acute comparisons of appetite and glycaemic responses between animal and plant-derived protein have only focused on soy and pea protein isolates compared to whey [ 33 , 34 , 35 ]. These studies have suggested that soy and pea protein isolates elicit comparable effects on insulin, glucose and appetite regulation; however, to the authors’ knowledge, the evidence comparing plant-derived protein isolates, such as potato and rice protein, to whey protein appears to be sparse.…”