What Is The Use Of Whey Protein?

Whey protein is a derivative of milk production with an amino acid profile that is closely related to the amino acids required by the human body. Whey protein also has proportionately more sulfur-containing amino acids and contains a relative surplus of a variety of essential amino acids. This combination would ideally result in an optimal balance of amino acids needed for muscle growth and recovery. Whey is an excellent protein source given its high biological value and amino acid composition. Whey is also a rich source of protein with diverse food properties for nutritional, biological, and functional applications. Because of whey's bioavailability and ease of dispersion in solution, it is looked upon as being the superior protein supplement for athletes to use as a post­workout meal.

Studies have indicated whey protein also has immuneenhancing properties. In a study by Bounous , the authors indicated that whey protein contains essentially more of the amino acid cysteine than casein. This is important because the amino acid cysteine is considered to be a ratelimiting substrate for the synthesis of glutathione (a major antioxidant of the body that is necessary for lymphocyte proliferation). In a comparison study of whey and casein on glutathione production in critically ill patients, whey protein (cysteine levels reported at 2.0-2.5%) increased glutathione concentrations well above those displayed by casein (cysteine levels reported at 0.3%). There is also evidence that mitochondrial function and the glutathione-dependent antioxidant system are important for the maintenance of proper structure and function of muscles.

Exercise puts much stress not only on the muscles, bones, and joints, but it also stresses the body's defense mechanisms, which is indicated by changes in glutathione status in plasma during intense exercise. Strenuous exercise also increases the production of free radicals and is characterized by an increased oxygen consumption and derangement of intracellular pro-oxidant/antioxidant homeostasis. These free radicals can be potentially injurious to genes, membranes, and other cell structures and may impede normal daily metabolic responses. Adequate antioxidants and foods that help manage oxidative stress and support the immune system may benefit athletes during and after exercise.

In addition to the unique amino acid profile of whey protein, it also features one of the highest percentages of branched­chain amino acids and is rich in vitamins and minerals. Diets high in branched-chain amino acids (BCAAs) demonstrate greater signs of muscle preservation when the body is in a catabolic state. This is due to the ability of BCAAs to improve nitrogen balance and serve as an energy source for skeletal muscle. Severe metabolic stresses such as sepsis, surgery, burns, and strenuous exercise are associated with accelerated requirements for BCAAs.