Role of protein in healthy ageing

With the global increase in ageing populations, a current and future key challenge is to improve health expectancy. It is well established that normal ageing is associated with a loss of muscle mass (sarcopenia), with concomitant loss of muscle function and increased risk of falls, reduced ability to perform daily tasks and subsequent reduced quality of life. Therefore, a balanced and optimal protein-energy homeostasis is recognised as a major dietary-related determinant of healthy ageing. This short article provides an overview of the current evidence relating to protein intake in older adults. Older adults may benefit from a protein intake above the recommended daily allowance, with an intake of ≥1.2 g/kg/day to help prevent age-related sarcopenia. The failure of older people to adequately regulate food and nutrient intake results in weight loss, and such changes have been termed the anorexia of ageing and have been attributed to multiple factors affecting the satiety cascade. The quality and timing of protein supplementation in addition to quantity is very important. To improve muscle protein synthesis, pulse feeding may be more effective than bolus feeding, but further evidence is needed. Key foci of ongoing research should be to provide robust evidence from trials in older adults to help define the optimum type and timing of dietary protein supplements.