What Is Whey Protein Powder?

Whey is a high-quality, concentrated milk-based protein food source. It is typically sold in powder form as a dietary supplement to increase your protein intake. Whey protein is marketed towards weightlifters and bodybuilders who want to add muscle mass and may require additional dietary protein as well as individuals trying to change their weight--weight loss, as part of a meal replacement program or weight gain, in addition to meals.

Identification

Whey is a byproduct of cheese that is manufactured from cow's milk. Before it becomes whey protein powder in is processed to remove the fluid (water), fat and other substances. What is left is component of milk protein. This protein substance is then hydrolyzed which breaks it up into smaller peptides or short amino acid chains. Your body can more easily absorb and use these peptides.

Main Types

A process known as ultra-filtration reduces the amount of lactose (milk sugar) in the whey and increases the protein concentration. At a concentration of at least 88 percent, whey protein becomes whey protein isolate (WPI). At less than that, it is known as whey protein concentrate (WPC). When more than one type is used, as in whey protein powder supplements, labels will typically refer to the mixture as a "whey protein blend." Whey protein powder is a gold standard among protein powder supplements.

High-Quality Protein

Whey protein exceeds a perfect score of 1.0, according to the USDA's "Protein Digestibility Corrected Amino Acid Score." In addition, whey protein is of high biological value, almost that of an egg, touted by nutrition experts as nearly a perfect protein food. It is of a higher quality than other protein sources, such soy protein. Proteins from animal products, such as eggs, meat and dairy, have a higher biological value than vegetarian proteins. Because it is high quality, whey protein (all types) is well absorbed and used by the human body. In addition, whey protein powders are a source of branched-chain amino acids (BCAA). These are particularly important for individuals in athletics or weightlifting.

Best-Rated Whey Supplements

Bodybuildingforyou.com rated 20 brands of whey protein concentrates, isolates and blend powder supplements on factors such as overall quality, cost per serving (CPS), cost per gram of protein (CPGP) and flavor(s). Generally, the isolates are the most expensive, the concentrates are the least expensive and the blends fall somewhere in between. The top picks based upon this criteria were EAS 100 Percent Whey, Scifit Econowhey and Optimum Nutrition Whey Protein Powder 100 Percent. All three are whey protein concentrates.

Immune System Booster

Glutathione is a water-soluble antioxidant in the body that protects cells and detoxifies harmful compounds such as heavy metals, carcinogens and peroxides. It is tied to the integrity of your immune system. Reduced levels are associated with diseases such as cancer, atherosclerosis and Alzheimer's disease. Whey protein increases glutathione levels in the immune system cells, and, in several research studies has been shown to improve immune function. In one such study, published in the "International Journal of Food Science and Nutrition" in 2007, researchers found that there is a relationship between the supplementation dosage and the change in white blood cell glutathione levels. Whey protein isolate supplementation of 45g daily for two weeks increased glutathione levels of immune system cells by 24 percent.