Embodiments of the present invention relate to the use of placental alkaline phosphatase, and other members of the alkaline phosphatase family, to enhance protein synthesis in the muscle as well as the survival of non-cancerous differentiated cells in the muscle, adipose and other tissues. The ability of alkaline phosphatase to selectively enhance the survival of healthy cells and increase protein synthesis has many therapeutic applications. The use of alkaline phosphatase may prevent the loss of body weight and muscle mass typically experienced by diseased (such as cancer) or aging patients, or developing fetuses subjected to harmful conditions, or by patients who are treated with a toxic therapy including chemotherapy.