Today, whey protein is often described as a "nutritionally perfect protein," in the sense that it contains all of the essential and nonessential amino acids required by the human body. Whey's amino acid profile is closely related to the optimal physiological needs of the human body, including an abundance of sulfur-containing amino acids, in a highly bioavailable form. Whey protein's quality is variously described by such terms as "high biological value"(BV), "high protein efficiency rating" (PER), and "high net protein utiliza-tion"(NPU).
Whey protein may also be the best candidate for maximizing muscle growth, for two reasons. Whey protein contains an optimal balance of amino acids for muscle growth, especially glutamine or glutamic acid, and taurine. L-Glutamine is the most abundant nonessential free amino acid in the body. The concentration of free glutamine appears to influence whether muscle will break down, due to low glutamine content, or build up, via high glutamine content.
Athletes suffering from overtraining syndrome seem to have decreased blood concentrations of glutamine. This may lead, in turn, to the suppression of immune functions and slow recovery time following exercise. Even patients recovering from trauma (surgery, burns, stress, chemotherapy, radiation, etc.) have an increased demand for glutamine. Such increased demand is probably the result of increased use of glutamine by the immune, antioxidant and detoxication systems, and the decreased integrity of various injured or irradiated tissues.
Whey protein's amino acid profile also features the highest percentages of branched-chain amino acids (BCAAs). Diets high in BCAAs demonstrate less muscle loss when muscle is being broken down, as is the case with severe infections, surgery, burns, calorie restriction, and strenuous exercise. This muscle and lean body mass sparing effect occurs because BCAAs serve as a direct energy source, thereby lessening muscle breakdown for energy. You can see why scientifically formulated and processed whey protein blends have quickly become the choice protein among competitive bodybuilders!
Along with having high amounts of glutamine (and/or its precursors, glutamic acid and proline), whey protein also contains high amounts of the essential sulfur-containing amino acid cystine, the disulfide form of the amino acid cysteine. Both cysteine and glutamine, along with glycine, are necessary for the synthesis of the tripeptide glutathione (GSH), one of the major detoxifiers (phase-II sulfonation) and antioxidants of the body. Enhancing glutathione levels also helps reduce the risk of infections by improving the immune system.
Whey proteins are in and of themselves rich in immune-enhancing subfractions, which, once digested in the gut, can be taken up by infection-fighting T-cells, increasing their number.
The complete list of immune- enhancing proteins in whey includes beta-lactoglobulin; alpha-lactalbumin; immunoglobulins; bovine serum albumin (BSA); glycomacropeptide (GMP); lactoferrin; lactoperoxidase; and lysozyme.
Beta-lactoglobulin is the most abundant whey protein component, making up approximately 50 percent of the whey protein. It binds fat-soluble vitamins, making them more available to the body.
Alpha-lactalbumin is the second most abundant whey protein component, making up approximately 20 percent to 25 percent of the whey protein. It is the primary protein found in human breast milk. Being high in tryptophan, an essential amino acid, potential benefits of alpha-lactalbumin include sleep regulation and mood improvement under stress. An excellent source of essential amino acids and BCAAs, alpha-lactalbumin is the only whey protein component capable of binding calcium.
Immunoglobulins (mostly IgG, with IgA and IgM), especially bovine serum albumin (BSA), make up approximately 10 percent to 15 percent of the whey protein. BSA is the predominant whey protein component found in colostrum, which is thought to provide immunity-enhancing benefits to infants, children and adults.
Lactoferrin makes up approximately 1 percent to 2 percent of the whey protein. It inhibits the growth of bacteria (including some pathogenic bacteria) and fungi, due to its ability to bind iron. Iron is an essential nutrient often required for bacterial growth. Lactoferrin also promotes the growth of beneficial bacteria such as L. bifidus, helping infants establish good microbial conditions in the intestines (eubiosis). It is also an antioxidant that naturally occurs in many body secretions, such as tears, blood, breast milk, saliva and mucus.
Lactoperoxidase makes up approximately 0.5 percent of the whey protein. Like lactoferrin, it inhibits the growth of iron-dependent bacteria.
Lysozyme makes up less than 0.1 percent of the whey protein. It also contains immunity-enhancing properties.
Glycomacropeptide (GMP) helps control and inhibit the formation of dental plaque and dental cavities.
Weighing the Benefits of Whey
Whey protein is an ideal source of protein and essential amino acids, perhaps most particularly for those ill and elderly with declining appetites; challenges with food preparation; less-than-optimal dentition; or poor digestive strength. Whey provides easily digested energy while boosting detoxication efficiency; antioxidant status; immune system efficiency; and lean body mass. Being low in carbohydrates and high in protein, whey is great for restricted carbohydrate diet strategies.
New preliminary, but exciting research reported in the January 2002 issue of Life Extension magazine suggests whey may be able to reduce stress and depression by lowering cortisol and increasing brain serotonin; improving liver function in those suffering from certain forms of hepatitis; helping chronic fatigue; improving athletic performance; and reducing blood pressure.
According to the Whey Protein Institute, whey protein has recently been shown to have potential positive impact in other areas, including appetite suppression, cholesterol reduction, and inhibition of dental plaque and dental caries.
Researchers at the Arkansas Children's Nutrition Center have found that whey and soy protein may help prevent breast cancer. The research, funded by the U.S. Department of Agriculture, was featured in the January 2004 issue of Cancer Epidemiology, Biomarkers & Prevention, an official journal of the American Association for Cancer Research.
Weighing the Different Forms of Whey
Whey protein concentrates (WPC) may vary from low (35 percent) to high (80 percent) protein, and from fairly low to moderately high lactose content. High protein WPC, as compared to isolates and hydrosylates, are the least processed, and therefore the richest in the immune-enhancing peptide subfractions; phospholipids; sphingolipids; conjugated linoleic acid; and tissue growth factors.
Whey protein isolates (WPI) and hydrolyzed whey protein (HWP) contain little to no appreciable lactose or carbohydrates, and are less that 1 percent fat, and 80 percent to 90 percent protein! However, the various processing methods disturb and imbalance to one extent or another the amino acid profile and immune-enhancing subfractions, or remove the lipids and growth factors that help make whey such an all-around "super-food."
To be of the greatest health benefit, whey protein supplements must be processed at a low temperature; whey's immune enzymes, peptides, lipids, and growth factors are denatured or otherwise damaged by the usual high temperature/short time (HTST) processing techniques used to make most cheese, of which most whey is a byproduct.
Therefore, the best all-around nutritional whey formulas are usually a blend of undenatured WPC, WPI and HWP.
- Micke P, Beeh KM, Buhl R. Effects of long-term supplementation with whey proteins on plasma glutathione levels of HIV-infected patients. Eur J Nutr February 2002;41(1):12-8.
- Bounous G, Gold P. The biological activity of undenatured dietary whey proteins: role of glutathione, Clin Invest Med August 1991;14(4):296-309.
- Tsuda H, Sekine K. Milk components as cancer chemopreventive agents. Asian Pac J Cancer Prev 2000;1(4):277-282.
- Barth CA, Behnke U. Nutritional physiology of whey and whey components. Nahrung February 1997;41(1):2-12.
- Wong CW, Watson DL. Immunomodulatory effects of dietary whey proteins in mice. J Dairy Res May 1995;62(2):359-68.
- Kent KD, Harper WJ, Bomser JA. Effect of whey protein isolate on intracellular glutathione and oxidant-induced cell death in human prostate epithelial cells, Toxicol In Vitro February 2003;17(1):27-33.
- Bounous G, Batist G, Gold P. Whey proteins in cancer prevention. Cancer Lett May 1991;57(2):91-4.
- Sharon K. Gerdes, W. James Harper, Ph.D., G. Miller, Ph.D. Bioactive Components of Whey and Cardiovascular Health. Applications Monograph, Cardiovascular Health, 2001. www.usdec.org/files/pdfs/11cardiovascular.pdf.
John Maher, DC, ABAAHP
Del Mar, California
Click here for previous articles by John Maher, DC, DCBCN, BCIM.