Bioactivity in Whey Proteins Influencing Energy Balance

Abstract

Obesity develops due to energy (food) intake exceeding energy expenditure. Nutrients that reduce the positive energy balance are thus being considered as therapies to combat obesity. Here, we review the literature related to the physiological, cellular and endocrine effects of intake of whey proteins, namely α-lactalbumin, β-lactoglobulin, glycomacropeptide and lactoferrin. Moreover, we discuss how dietary composition and obesity may influence whey protein effects on the above parameters. Evidence suggests that intake of whey proteins causes a decrease in energy intake, increase in energy expenditure, influence insulin sensitivity and glucose homeostasis and alter lipid metabolism in the adipose, liver and muscle. These physiological changes are accompanied by alterations in the plasma levels of energy balance related hormones (cholecystokinin, ghrelin, insulin and glucagon-like peptide-1) and the expression of catabolic and anabolic genes in the above tissue in the direction to cause a negative energy balance.

Whey protein isolate counteracts the effects of a high-fat diet on energy intake and hypothalamic and adipose tissue expression of energy balance-related genes

“…In the obese state, the effects of WPI on energy intake appear to be lost, yet dietary proteins still attenuate HFD-induced obesity ( 10 , 20 – 23 ) . The discrepancies between these data and those of the present study, in particular, with regard to energy intake, may be related to the differences in dietary macronutrient and micronutrient composition (45 % energy as fat v. 60 % energy as fat, casein v. soya as the control and altered Ca content in the diet) and/or the study duration (8 weeks v. up to 20 weeks) that were used to assess the energy balance impact of whey proteins ( 19 ) . It is also possible that some of these discrepancies may have arisen due to the fact that we subjected the group-housed mice to a single housing environment of the TSE Phenomaster cages (TSE systems) to measure their energy intake.…”

“…Also, using healthy lean subjects or rodents, a number of studies have reported a short-term reduction in energy intake and an increase in thermogenesis following WPI intake in comparison with other dietary proteins including casein ( 7 , 11 – 13 ) . Although there are discrepancies ( 14 – 17 ) , it is largely recognised that WPI intake influences the balance between energy intake and energy expenditure in the lean state ( 18 , 19 ) . In contrast, the effects of WPI on energy intake and energy expenditure in the HFD-induced state are less well known, although WPI has consistently been shown to reduce HFD-induced body-weight gain and adiposity ( 10 , 20 – 23 ) .…”

Age‐ and duration‐dependent effects of whey protein on high‐fat diet‐induced changes in body weight, lipid metabolism, and gut microbiota in mice

“…Because of the specific amino acid composition including branched chain amino acids, intake of these proteins has been shown to bring about several health benefits. Notably, a diet supplemented with whey protein has been found to modulate appetite, and ileal expression and plasma levels of satiety hormones such as insulin, ghrelin, cholecystokinin, and glucagon-like peptide 1 (Chungchunlam, Henare, Ganesh, & Moughan, 2015;McAllan, D Cotter, & M Roche, 2012;Pal, Radavelli-Bagatini, Hagger, & Ellis, 2014). Additionally, in several studies in which whey protein constituted the main protein source of a high-fat diet (HFD), this protein ameliorated the impairment of glucose tolerance, and reduced the increase in body weight and adiposity compared to other dietary proteins, such as casein (CAS, a nonwhey milk protein which is the main component of cheese), soy, meat, and fish proteins (Madsen, Myrmel, Fjaere, Liaset, & Kristiansen, 2017;McAllan et al, 2013;Pilvi, Korpela, Huttunen, Vapaatalo, & Mervaala, 2007).…”

Preventive Effects of Chitosan Coacervate Whey Protein on Body Composition and Immunometabolic Aspect in Obese Mice

“…Evidence suggests that eating WP causes the decrease in calorie intake, increased basal energy expenditure, and modulates insulin sensitivity and glucose homeostasis, leading to changes in lipid metabolism in adipose tissue, liver, and muscle [ 39 – 42 ]. The AMPK and adiponectin are key molecules to metabolic responses in different tissues [ 43 , 44 ]; they are involved in the preventive response against negative physiological processes caused by the consumption of a diet high in saturated fatty acids.…”

“…Finally, there is plenty of evidence suggesting that the intake of WP may lower consumption of calories, increase baseline energy expenditure, and improve insulin sensitivity and glucose homeostasis, thus leading to changes in lipid metabolism in adipose tissue, liver, and muscle [ 39 – 42 ].…”