Dairy proteins: the preferred source of protein for maintaining muscle mass in older people?

As people age, a gradual loss of muscle mass is observed (sarcopenia). This naturally has consequences for older people’s mobility and independence, but also leads to a state of vulnerability to environmental stressors (illness, stress, etc.). This loss of muscle mass results not only from reduced physical activity but also from the loss of the anabolic effect of meals, which is explained by the muscle tissue’s reduced sensitivity to the effects of dietary amino acids. Several nutritional strategies are now available, based on modifying both the quantity and quality of protein intake in older people. These include high-protein meals, rapidly digestible proteins, leucine-rich proteins, and the modulation of oxidative stress and low-grade inflammation that develop with ageing. In this context, various milk proteins have been tested in older adults, based on their qualitative properties (amino acid composition) and/or their physical properties (solubility).