We get questions everyday from people that have questions about protein and how it effects performance and endurance.  Most people are rightfully confused because of overwhelming amount of inaccurate information that’s available.  We’ve assembled this overview to explain the basic differences in whey proteins.  If you have a question that’s not addressed, post it in the blog and we’ll make sure you get the information you’re looking for.

Whey Protein

Whey protein is a high quality complete protein containing all of the essential amino acids required by the  body each and every day. There are several different methods that are used today evaluate protein quality.  No matter which method is used, whey proteins have been proven to be an excellent, pure source of protein.

To help prevent the breakdown of muscle tissues, whey protein contains beta-lactoglobulin, a rich source of  branched-chain amino acids (BCAAs). Whey protein is also a rich source of the amino acid Cystein and has been shown to increase glutathione levels in the body. Glutathione is an antioxidant that helps provide an added boost to the immune system.

Whey proteins have a Protein Digestibility Corrected Amino Acid Score (PDCAAS) of 1.14. The  reported score is 1.0, which is the maximum value allowed by the USDA for reporting purposes. The PDCAAS is the USDA’s officially approved method of scoring protein quality.

Another method used to measure protein quality is the Protein Efficiency Ratio (PER). Whey proteins have a PER of 3.2, making it one of the highest single source proteins. The PER rating is based upon the evaluation of the growth of animals consuming a fixed amount of dietary protein from a single source. As the PER increases, so does the quality of the protein.

Biological Value (BV), another measure of protein quality, measures the amount of protein that is retained from the absorbed protein for maintenance and growth. It measures the fraction of the nitrogen in the diet that remains after the nitrogen losses in the waste products have been subtracted. Whey proteins have a biological value of 100, which is higher than the value for casein (milk protein), soy protein, beef, or wheat gluten

protein chart

Whey protein is not a single protein; it consists of a number of individual protein components. In recent years new technology has enabled manufacturers to isolate and further purify some of these individual components, including technology that allows the protein to be isolated from the fats and sugars (whey isolate or hydrolysate). Due to its lower molecular weight, whey in its isolate form is more quickly and fully absorbed than other forms. The following is a list of the individual components in whey protein:

  • Beta Lactoglobulin: The most abundant whey protein component, making up approximately 50-55% of the whey protein. Binds fat soluble vitamins making them more available to the body. Provides an excellent source of essential and branched chain amino acids (BCAAs), which help prevent muscle breakdown and spare glycogen during exercise. Hydrolyzed versions are often used in infant formulas to reduce potential allergic reactions.
  • Alpha-lactalbumin: The second most abundant whey protein component, making up approximately 20-25% of the whey protein. The primary protein found in human breast milk. High in tryptophan, an essential amino acid; potential benefits include sleep regulation and mood improvement under stress. Excellent source of essential amino acids and BCAAs. The only whey protein component capable of binding calcium.
  • Immunoglobulins: Makes up approximately 10-15% of the whey protein. Provides immunity enhancing benefits to infants and others. Predominant whey protein component found in colostrum.
  • Bovine Serum Albumin: Makes up approximately 5-10% of the whey protein. Large sized  protein with a good essential amino acid profile and fat binding properties.
  • Lactoferrin: Makes up approximately 1-2% of the whey protein. 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. The USDA recently approved the use of lactoferrin on meat to prevent the growth of pathogens such as E. coli and Salmonella. Promotes the growth of  beneficial bacteria such as Bifidus. Helps infants establish good microbial conditions in the intestines. Regulates iron absorption and bio-availability. May help to reduce inflammation. An antioxidant that naturally occurs in many body secretions such as tears, blood, breast milk, saliva and mucus.
  • Lysozyme Makes up less than 0.1% of the whey protein. Contains immunity enhancing properties.


Whey Protein Isolate

Whey protein isolate is the purest form of whey protein and contains 90-95% protein. It contains little, if any, fat or lactose. In contrast, whey protein concentrate can have a protein content ranging from 25% to 89%. It will contain some lactose, fat, and minerals. As the protein level increases the amount of lactose decreases. Whey protein concentrate at 70% – 80% protein content is the form most readily available as a protein powder supplement.7

Whey protein, a milk derivative, is by far the most popular protein on the market and comes in various forms, from the lower grade, higher fat whey concentrate to the highly purified isolate or hydrolysate form (the latter of which provides the benefits of microfractions and is low in fat and lactose). Most of the whey protein on the market is usually found as ion-exchange, a process using electric charges to extract the protein. There are some advanced procedures (like cross flow microfiltration) that produce higher quality whey, with subsequent added benefits over ion-exchange whey isolate in preserving key microfractions which are essential to its benefits. Whey protein isolate that is not heat-treated contains key microfractions, like alpha lactalbumin and glycomacropeptides, which can both positively support immune function. Some of the microfractions or growth factors found in whey protein can even enhance IGF-1 levels which can increase lean muscle mass—good news for hard training athletes. Whey protein has a very high biological value which means it’s most readily utilized by human muscle tissue thus making it a very fast absorbing protein and anabolic as a result. Some users of whey protein concentrate may experience bloating or gas due to its lower quality, but it is very cost effective. Due to its low molecular weight, the higher quality isolate and hydrolysate forms are easier to absorb preventing any digestion pitfalls.

A properly selected whey isolate contains high amounts of ßeta-lactoglobulin, alpha-lactalbumin, Glycomacropeptides, Immunoglobulins, Bovine Serum Albumin, Lactoferrin, Lactoperoxidase, Lysozyme and a high amino acid profile. All of these elements are very important to heavy training athletes, as these compounds can aid in reducing the risk of over training and aid in the digestion process. Whey isolate also gives a quick “boost” in aminos due to its easy and rapid digestion, especially useful in post training when the body needs those aminos to replenish itself. However, it is not a singular source of all the aminos needed to optimally repair broken down muscle tissue.

Quality whey protein isolate provides key microfractions, has a very high concentration of BCAAs for  positive effect on lean muscle mass and lower muscle breakdown (whey protein contains about 25% BCAAs—the highest of any protein source), enhances glutathione levels in the body (glutathione is the body’s most powerful natural antioxidant and is a key part of the immune system), features high digestibility and absorption rate, contains virtually no lactose and very low fat, and provides about 50% of the essential amino acids.


Hydrolyzed Whey Protein

The process of hydrolysis breaks the protein chains down into smaller segments called peptides. Hydrolyzed whey protein is more easily digested and has a reduced potential for allergic reactions versus non-hydrolyzed whey protein. The quality of the protein, however, remains very high. Sports nutrition products and infant formulas often use hydrolyzed whey protein for these reasons. A recent clinical study also found that a specific type of hydrolyzed whey protein was helpful in lowering blood pressure. Learn more about protein here.


Whey Protein References

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Appel, L. et. al., 1997. “A clinical trial of the effects of dietary patterns on blood pressure.” The New England Journal of Medicine, 336(16):1117-1124.

FitzGerald, R.J., Meisel, H., 1999. “Lactokinins: Whey protein-derived ACE inhibitory peptides.” Nahrung 43:165-167.

FitzGerald, R.J., Meisel, H., 2000. “Milk protein-derived peptide inhibitors of angiotensin -1-converting enzyme.” British Journal of Nutrition. 84:S33-S37.

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Esmarck, J.L., Andersen, Olsen, S., Richter, E.A., Mizuno, M., and Kjaer, M., 2001, “Timing of postexercise protein intake is important for muscle hypertrophy with resistance training in elderly humans.” Journal of Physiology, 535.1:301-311.

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McCarron, D. A., 2000. “Dietary calcium and blood pressure control: lessons learned from controlled clinical trials.” Bulletin of the International Dairy Federation, 353:6-9.

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Pihlanto-Leppala, A. et.al., 2000. “Angiotensin I-converting enzyme inhibitory properties of whey protein digest: concentration and characterization of active peptides.” Journal of Dairy Research, 67:53-64.

Pins, J., and Keenan, J., 2002. “The antihypertensive effects of a hydrolyzed whey protein isolate supplement (BioZate 1®).” Cardiovascular Drugs and Therapy, 16(Supp. 1):68.

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Bounous, G., Baptist, G., and Gold, P., 1991. “Whey proteins in cancer prevention.” Cancer Letters 57:91. Hakkak, R., Korourian, S., Shelnutt, S. R., et. al., 2000. “Diets containing whey proteins or soy protein isolate protect against 7,12-Dimethylbenz (a) anthracene-induced mammary tumors in female rats.” Cancer Epidemiology, Biomarkers & Prevention, 9:113-117.

Hakkak, R., Korourian, S., Ronis, M.J., Johnston, J., and Badger, T., 2001. “Dietary whey protein protects against azoxymethand-induced colon tumors in male rats.” Cancer Epidemiology, Biomarkers & Prevention, 10:555-558.

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Takada, Y., Aoe, S., Kumegawa, M., 1996. “Whey protein stimulates the proliferation and differentiation of osteoblastic MC3T3-E1 Cells.” Biochemical and Biophysical Research Communications, 223:445-449.

Tsai, W., Chang, W., Chen, C.H., and Lu, F., 2000. “Enhancing effect of patented whey protein isolate (Immunocal) on the cytotoxicity of anti-cancer drug.” Nutrition and Cancer, 38(2):200-208.

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Wong, C.W. et al., 1997. “Effects of purified bovine whey factors on cellular immune functions in ruminants.” Veterinary Immunology and Immunopathology, 56:85-96.

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Beeh, M., Schlaak, J.F., Buhl, R., 2001. “Oral supplementation with whey proteins increases plasma glutathione levels of HIV infected patients.” European Journal of Clinical Investigation, February, 31 (2):171-178.

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