Milk proteins and human health

Abstract

Cow's milk proteins and related bioactive peptides may have significant effects on human health across the life span. Both casein and whey protein are proposed to play a role in prevention of chronic age-related conditions including adverse metabolic health and type 2 diabetes, cardiovascular risk, muscle wasting and sarcopenia, and bone health and osteoporosis. Cohort studies have shown dairy to be associated with decreased cardiometabolic risk, through improved metabolic health. Intervention studies have shown milk proteins to promote postprandial insulin secretion and better glycemic control and, under some conditions, improve postprandial lipemia and hypertension. Branched chain amino acids also promote muscle anabolism, important for muscle mass maintenance, and may aid mobility during aging. Dietary protein may suppress satiety and food intake on a per kilojoule basis and has been hypothesized to aid preferential fat rather than lean mass loss during energy restriction. Milk proteins may also be beneficial for bone health during aging and also conversely during growth and development in early life. While public health recommendations for breastfeeding underpin infant nutrition, commercial formulas may be required for mothers unable to breastfeed where cow's milk protein formulas aim to optimize infant health. In this chapter, evidence that underpins potential health benefits of milk proteins is reviewed, based on current human clinical trials, with particular focus on metabolic health.