Protein Utilization

The whole egg has a net protein utilization of approximately 48%, the closest of any food to breast milk. Tracking nitrogen output in urine is the standard method for measuring protein utilization efficiency. Protein not used for building and repair is either excreted as waste through the kidneys or converted into glucose and burned as fuel. Most dietary protein is absorbed through the digestive tract, but only a small portion is directed toward repairing damaged tissue and building new proteins. Net protein utilization measures what fraction of dietary protein is actually converted into body tissue, which is more meaningful than total protein content. Protein that is not utilized for tissue building is converted to glucose and burned as fuel. Protein utilization depends on both the protein source and the quality of digestive conditions. The body manufactures approximately 50,000 different proteins per day, each assembled from different combinations of amino acids. Impaired hydrochloric acid concentration reduces the body's ability to break down and utilize protein.