Sarcopenia
Protein intake and physical activity are important stimuli for muscle protein synthesis. A number of expert groups have proposed an increase in dietary protein recommendations for older age groups to 1.0-1.2 g/kg body weight per day.
Key nutrient supplementation in older adults is of interest in the prevention of sarcopenia and frailty, since it is a simple, low-cost treatment approach without major side effects.
Puppy nutrition
Protein in excess of these levels is metabolized and leads to an increase of the glomerular filtration rate, and increased urea excretion in the urine, with no evidence of damage to the kidneys. However, addition of protein past these requirements is not recommended, although the NRC has not quantified a safe upper limit. Considering that the energy density of protein is similar to that of carbohydrates, an excess of protein in the diet may lead to fat deposition and weight gain. This excess weight can lead to abnormal joint development, potentially giving rise to joint issues in the future. Additionally, excess of some amino acids may also have detrimental impacts; for example, excess lysine will negatively antagonise arginine. The minimal requirement laid out by the NRC is 180g/kg (18%) DM of crude protein, with a recommended allowance of 225g/kg (22.5%) DM. With this in mind, it is also important to consider the quality and digestibility of the protein used.