Protein Quality And Immuno - Enhancement

Similar to carbohydrates, protein might have positive immunomodulating effects. One must remain cognizant of the fact that proteins differ in quality and that this might impact your choice of a post-exercise protein source. Protein quality is usually measured in one of three ways -

1) The Protein Efficiency Ratio (PER)

2) Biological Value (BV)

3) The Protein Digestibility Corrected Amino Acid Score (PDCAAS).

The PER uses a procedure in which immature rats are fed a measured amount of protein and weighed over a given time. The PER is then calculated by dividing the weight gain by the protein intake. Based on a recent study in Fisher, 344 weanling rats, the corrected PER and the foods with the best protein quality, were egg (3.24), beef sirloin (3.16), and chicken breast (3.07), all of which were significantly different from milk powder (2.88) and casein (2.50).

Biological value measures the amount of protein retained per gram of protein absorbed. If a given protein provides all the essential amino acids in the correct proportions and is readily absorbed, the BV score will approach . On the other hand, if the protein is deficient in one essential amino acid, then its BV score will be much lower. The newest measure of protein quality is the PDCAAS. This method takes into consideration the advancements made in amino acid analysis and protein digestibility, the availability of data on digestibility of protein, the individual amino acids found in a variety of foods, and the reliability of human amino acid requirements and scoring patterns. The PDCAAS is a simple approach for evaluating the protein quality of foods and has been validated based on metabolic balance studies in humans. Proteins are rated on a scale of The scores derived from this method rate egg white, casein, and soy protein isolates at with beef closely behind. Moreover, high-quality protein can be found in various foods like eggs, milk, poultry, fish, and lean beef sirloin. There are also many types of high-quality protein supplements on the market such as whey, milk isolates, caseinates, soy isolates, and even some vegetable protein.