Efficiency of Utilization of Amino Acids

Dietary amino acids are used for the synthesis of body protein, animal products, and many other nitrogen-or sulfur-containing compounds with important physiological functions. The utilization of dietary amino acids in the course of digestion, absorption, and intermediary metabolism is affected by many internal and external factors, the knowledge of which may be of vital importance for the estimation of amino acid requirements and the formulation of well-balanced diet. The effect of dietary level of amino acids on their utilization is well known. The dominant factor affecting the efficiency of utilization of an amino acid is its proportion in the diet relative to the requirement. The efficiency of utilization of amino acids for growth and maintenance was calculated from the retained amount increased by the maintenance requirements. Studies on amino acid retention and oxidation have shown that the efficiency of utilization is inherent to individual amino acids and may differ even under comparable dietary conditions.