Milk protein for improved metabolic health: a review of the evidence

Abstract

Epidemiological evidence shows that consumption of dairy products is associated with decreased prevalence of metabolic related disorders, whilst evidence from experimental studies points towards dairy protein as a dietary component which may aid prevention of type 2 diabetes (T2DM). Poor metabolic health is a common characteristic of overweight, obesity and aging, and is the forerunner of T2DM and cardiovascular disease (CVD), and an ever increasing global health issue. Progressive loss of metabolic control is evident from a blunting of carbohydrate, fat and protein metabolism, which is commonly manifested through decreased insulin sensitivity, inadequate glucose and lipid control, accompanied by a pro-inflammatory environment and hypertension. Adverse physiological changes such as excess visceral adipose tissue deposition and expansion, lipid overspill and infiltration into liver, muscle and other organs, and sarcopaenia or degenerative loss of skeletal muscle mass and function all underpin this adverse profile. ‘Sarcobesity’ and sarcopaenic diabetes are rapidly growing health issues. As well as through direct mechanisms, dairy protein may indirectly improve metabolic health by aiding loss of body weight and fat mass through enhanced satiety, whilst promoting skeletal muscle growth and function through anabolic effects of dairy protein-derived branch chain amino acids (BCAAs). BCAAs enhance muscle protein synthesis, lean body mass and skeletal muscle metabolic function. The composition and processing of dairy protein has an impact on digestion, absorption, BCAA kinetics and function, hence the optimisation of dairy protein composition through selection and combination of specific protein components in milk may provide a way to maximize benefits for metabolic health.

Future Challenges of Whey Proteins

“…Whey proteins help to control the blood glucose levels and also provides additional beneficial for weight management which is a concern for type-2 diabetics (Shankar and Bansal, 2013). Ingestion of whey proteins lead to more rapid secretion of insulin than micellar casein (McGregor and Poppitt, 2013).…”

“…This effect is thought to be related to the sulfhydryl component, particularly cysteine and its link with glutamic acid in the production of glutathione. In a study by Rosaneli et al (2002), rats fed a whey protein concentrate showed a 41% reduction in ulcerative lesions caused by ethanol ingestion while, a 73% reduction rate was observed following repeat doses of whey (Marshall, 2004;McGregor and Poppitt, 2013).…”

Effectiveness of Whey Protein Supplement in Resistance Trained Individuals

“…Selective elution, also known as ion exchange chromatography, is the process most often used to produce whey protein isolates [14]. Additional hydrolysis with enzymes or acids provides a way to breakdown the structure of protein containing in whey [22]. As the acids hydrolysis process would also lower the quality and biological value of protein, the addition of proteolytic enzymes, followed by purification procedures is greatly preferred [32].…”

“…All of these components have been associated with the potential to improve general health outcomes and disease prevention reduce immunosuppression attenuate muscular inflammatory related damage optimize recovery process and resistance training outcomes in athletes and enhance metabolic health in general population [19][20][21][22][28][29][30].…”

“…of the manufacturing process. A range of processed milk proteins (concentrates, isolates, hydrolyzate or peptides) has been used for different purposes including change in metabolic health in young or elderly people or training optimization outcomes in untrained recreationally active or well trained athletes [19,[22][23][24][25][26].…”