Protein intake is important to restore and build up skeletal muscle and to maintain optimal health and performance. When baseline dietary protein is suboptimal, supplemental protein enhances muscle mass and, to a lesser extent, muscle strength.1,2 However, the effects of protein supplementation are small when the usual intake already meets protein requirements, since amino acids in excess are oxidized.2-4 Currently, protein supplements have gained popularity for increasing muscle mass in sports medicine as well as for preventing sarcopenia in older adults and in chronic disease-related cachexia5; however, controversy exists over the advantages and disadvantages of different proteins.