The fact that so many different kinds of high-tech protein supplements are now available doesn't make understanding things any easier. The ads all sound scientific, a fact that's underscored by the inclusion of flaky medical references and sometimes even quotes from medical professionals, who appear to endorse the product's efficacy. The many scientific-sounding terms that are bandied about in the ads, such as ionisation, cross-flow filtration and other equally technical sounding words, heighten an already confusing subject.

Q: Some nutrition texts list the biological value (BV) of whey as 104, yet many advertisements for whey protein supplements boast of biological values as high as 159. Why the apparent discrepancy? NOTE: BV's higher than 159 have now been touted by some supplement marketers.

A: Biological value is an attempt to measure how efficiently protein is used in the body. To determine a food's BV, scientists provide a measured intake of protein, then note the nitrogen uptake vs. nitrogen excretion. That's a gross simplification, since the actual process is more complex. In theory, a biological value of 100 is maximal. The BV for whey is often listed at 104 because the extra 4 percent represent a margin of error in the calculation. Even so, biological value is not a universally accepted measure of protein quality because of several factors. For example, BV testing is always done in the fasting state, which affects nitrogen uptake differently from what takes place when subjects are in a fed state. Simply put, not eating changes the way the body absorbs nitrogen in protein. The 159 BV value for whey you see in some advertisements comes from a study in which the author quoted two earlier researchers who had claimed a 159 BV for whey protein. The problem is, the researchers had confused BV with chemical score, which involves measuring the activity of amino acids in the body. The 159 figure refers to whey's chemical score, not its biological value. A true biological value of 159 for a protein just isn't possible, since the maximum BV is around the 100 mark.

Q: A number of high-tech terms are frequently mentioned in ads for commercial whey products, such as ionisation and cross-flow filtration. What do they mean, and are some processing techniques better than others?

A: To understand the answer to that question, you need to know the history of whey proteins. Until about 25 years ago whey was considered a waste product of the dairy industry. You made cheese or casein from milk, and the by-product of the manufacturing process was whey. The question facing dairy companies was what do we do with all that whey?

In its raw state, whey is about 6 percent solids, is an un-appetising greenish colour and both looks and tastes terrible. It spoils easily due to its high content of lactose (milk sugar), which is a favourite food of bacteria. For the most part whey didn't appear to hold much commercial promise for dairy factories. As a result, they simply dumped their whey in nearby rivers and streams, which quickly led to an environmental hazard due to the high biological oxidation demand of whey solids, something the government frowned on.
The dairy factories began processing whey into a powder containing 11 percent protein, 72 percent lactose and some ash, or minerals. It was yellow, and it didn't taste great. Some factories persisted in dumping whey, such as one in Australia that built a pipeline to dump it directly into the ocean. Eventually, a membrane system was developed to filter whey.
The first process was called ultra-filtration, and the French developed it. It involved separating the whey protein from the ash and lactose, which resulted in a 35 to 70 percent protein content. The process continued to be refined, particularly for the Japanese market, where there's a high tax on the import of any protein that has less than 80% protein content. The Japanese were huge consumers of whey because they used it as a substitute for egg white in certain foods.

The next big breakthrough in whey processing occurred about 15 years ago, when a Welsh engineer developed the ion-exchange process. This process revolved around the positive and negative charges, or ion properties, of whey proteins. It featured the use of a resin to isolate the protein material from the whey, adjusting the PH, or acidity level, along the way. This was followed by ultra-filtration methods to further concentrate the protein. He called his product Bipro whey protein isolate. It provided an unprecedented 90 percent protein content while containing less than 1- percent lactose. The inventor of this ion-exchange process patented its use in all types of applications. Upon later learning that he had terminal cancer, however, the Welshman put his whey patents up for sale.

A Company that owned a dairy business in Minnesota purchased them. That company evolved to Davisco, which today manufactures Bipro. The important point is that this product is a true whey protein isolate, which means that it contains more than 90 percent protein. Since Davisco now had a lock on the resin method of manufacturing a whey protein isolate, competing dairy companies sought another way to produce higher-protein whey powders that wouldn't infringe on patents held by Davisco. Enter micro-filtration, which featured filtering membranes with microscopic holes. Still another process that used even smaller holes in the filtering membranes for whey was called nanofiltration.

The smaller the holes in the filtering membranes, the more expensive the process. The usual whey processing used today involves an initial ultra-filtration, which brings the protein content to 75 to 80 percent. The resulting whey liquid is run through either micro- or nano-filtration, screening out more fat and lactose. That results in the whey's having about 1 percent fat content, while the protein content goes up to 81 to 86.5 percent. Cross-flow filtration is more of an advertising ploy used by a particular company than the new technical advance the ads imply. In reality, this type of whey processing is no better than the others.

Q: What are the drawbacks and advantages of the various whey-processing techniques?

A: True ion-exchange whey is clear in solution, an advantage if you're using it in bottled protein drinks. This is the Bipro whey, since Bipro's maker, Davisco, still retains the patents for producing ion-exchange whey.

Among the disadvantages of ion exchange whey are the high price and limited supply. In addition studies show that ion-exchange whey protein isolates sometimes contain as much as 70 percent beta-lactoglobulin and as little as 10 percent alpha-lactalbumin. Those percentages aren't even similar to the ones that are naturally found in cow's milk and are significantly different from the proportions found in mother's milk, where alpha-lactalbumin content is high and there's no beta-lactoglobulin present.

The significance is that beta-lactoglobulin is considerably more allergenic than alpha-lactalbumin in humans. The biologically active whey protein fractions, such as lactoferrin, are just about non-existent in true ion-exchange whey protein isolate. This has to do with the processing system used to produce ion-exchange whey, which doesn't favour the retention of the smaller vital whey protein fractions. It's a notable disadvantage because the limited whey fractions have considerable health benefits.

The primary disadvantage of the filtered whey proteins as opposed to the ion-exchange variety is that the filtered types aren't as pure. True ion-exchange protein-specifically, Bipro-is 90 percent protein, while filtered whey protein isolates average 86.5 percent protein on an as is basis. The filtered whey also contains slightly higher fat and lactose contents, although the differences aren't significant enough to matter to a consumer. The advantages of filtered whey proteins include higher levels of valuable whey protein fractions, such as proteose peptone and lactoferrin, and the much-heralded glycomacropeptides. Lactalbumin is often used as a synonym for whey protein, which isn't quite correct.

In the protein industry the word lactalbumin refers to a protein powder manufactured from whey using a high heat process. Lactalbumin contains abnormally high amounts of heat-denatured beta-lactoglobulin. Since high heat and acid are used in the manufacture of lactalbumin, most of the vital whey protein fractions present in the powder become denatured, or broken apart.
The original ion-exchange proteins offered to bodybuilders about five years ago were probably the lowest quality from a nutritional standpoint when compared to ultrafiltered whey.
One frequent criticism of ultrafiltered whey is that it has a higher fat content. But the truth is that all whey proteins contain some fat, since completely removing all traces of fat would require hydrolysing the protein, which in turn denatures the protein. Once protein is denatured, its biological activity is gone.

The fat bound in the whey protein structure is higher in saturated fat and cholesterol than normal milk fat. The reason you don't often see the true fat content of whey supplements listed is that the bound fat in the whey can only be analysed by acid hydrolysis, which would denature the native proteins in the whey. The fat content of whey is usually analysed by ether extraction, which only measures free fat; not the fat bound to proteins. Using the ether extraction technique results in a much lower-though inaccurate-listing of the fat content of a whey protein supplement. In fact, I've yet to see a commercial whey protein supplement that has a true listing of its fat and cholesterol content on the label.

Any milk-derived protein supplement or meal replacement that lists zero fat and cholesterol on the label is misleading consumers and may be guilty of fraudulent label practices. For every 50 grams of milk-derived protein per serving, the cholesterol content will probably equal 50 to 75 milligrams. In 20 grams of whey protein there will be at least 15 milligrams of cholesterol, and if one of the primary ingredients listed on the label is whey protein concentrate, the cholesterol levels are probably closer to 50 milligrams or higher.

Q: So the hidden fat in all whey protein supplements is a disadvantage?

A: Not unless you consider the various growth factors found in whey proteins a liability, which I don't think most bodybuilders interested in building muscle would tend to do. Included in the fat globule membrane of whey or milk are various anabolic factors, such as IGF-1. If you were to completely eliminate all the fat in whey, you'd also be throwing out that coveted anabolic factors.

Q: Mother's milk is often called the ideal protein, but are the protein proportions in mother's milk ideal for active, athletic adults?

A: Human mother's milk contains a balance of 50 to 60 percent whey protein-to-40 to 50 percent casein protein. That's a far different balance from what you find in cow's milk, which is about 80 percent casein and 20 percent whey protein. Also, the types of proteins present in the two milks are significantly different. Human mother's milk contains as much as 17 percent lactoferrin, while cow's milk contains about 1 percent lactoferrin. The dominant whey protein fraction in human mother's milk is alpha-lactalbumin, while the dominant whey protein fraction in cow's milk is beta-lactoglobulin. Human mother's milk doesn't contain any beta-lactoglobulin, a highly allergenic protein in humans compared to alpha-lactalbumin. Nature doesn't do anything by chance, and the high content of lactoferrin found in mother's milk is there for a reason. Among other properties lactoferrin has antiviral activity and is a potent immune system booster. That's clearly advantageous for newborn humans, who lack full immune system function. From an athletic standpoint, lactoferrin may reduce tissue regrowth time. Some studies have shown that it may assist in increasing tissue regrowth. Lactoferrin is one reason that you can't duplicate mother's milk. The cost of purified lactoferrin is prohibitively expensive. Another factor making it difficult to duplicate mother's milk is the beta-lactoglobulin content of cow's whey protein. Infant formula companies have experienced considerable difficulty in making efficacious products from cow's milk protein. In order to make the formula less allergenic to human infants, they usually hydrolyse the whey protein to a high degree. If the beta-lactoglobulin is sufficiently hydrolysed, its allergenicity in humans is decreased. It may be difficult to exactly duplicate human mother's milk, but one can at least try to achieve the proper whey-to-casein ratio. It's only logical to conclude that if nature makes mother's milk 50 percent whey protein-to-50 percent casein, that ratio is probably best for growing humans. Nature didn't make mother's milk from 100 percent whey protein or 90 percent casein. It seems obvious that growing humans should thrive on the natural balance of whey protein and casein that's found in mother's milk.

Q: What constitutes a good whey protein supplement?

A: Contrary to those ubiquitous ads, the type of whey processing, whether filtration or ion exchange, has little to do with the ultimate quality of the supplement. All changes in PH levels or exposure to high temperatures affect protein quality by promoting denaturation, the permanent breakdown of the natural protein structures. You want to maintain the native structure of the various protein fractions contained in whey as much as possible. You're after biologically active proteins, and you want to avoid denaturing them because it would minimise their biological activity and, therefore, their value to customers. The manufacturers who supply the raw protein material vary in their processing techniques, so in many factories each batch of protein may differ in quality from the next. Even the way the cows are fed has an effect on protein quality. All things being equal, the factory supplying the whey determines the quality of the finished product. Some factories use harsher processing techniques that destroy the delicate whey protein fractions. You cannot, however, completely avoid denaturation because of the necessity of killing existing bacteria before filtering the whey. That involves pasteurisation, or the use of heat, which unavoidably alters some protein. As a consumer you want to look for a company that actively does everything it can to preserve the vital whey protein fractions. Some companies don't bother to analyse the batches of whey they receive and often get their whey from various sources. You also want to look for whey that contains the greatest amounts of those important whey protein fractions. Generally, whey protein concentrate contains more lactoferrin than whey protein isolates. In fact, the concentrates contain double the amount of health-promoting immunoglobulins than isolates have. In addition, the concentrates are less expensive. Thus, from both growth promoting and health standpoints whey protein concentrates may be best for bodybuilding purposes.

Q: Many people worry about the lactose, or milk sugar, content of whey because of lactose intolerance. Which types of whey are best for them?

A: Whey protein concentrate contains 6 to 7 percent lactose, while whey isolates contain only 1 percent lactose. It sounds significant until you consider that for every 100 grams of whey protein isolate you get 86.5 grams of protein and 1 gram of lactose. For the same quantity of whey protein concentrate you get 80 grams of protein and six to seven grams of lactose. I don't think that amount would approach the threshold that results in symptoms of lactose intolerance. What people should be concerned about is maintaining the health of their intestinal membranes, since that's the area most likely affected by dietary changes. One way to do that is to take glutamine. The amino acid fuels the regeneration of the intestinal lining, which breaks down every three days. The body also uses up available glutamine under high-stress conditions, as it's a favoured fuel of immune cells. Anyone who's under stress, including the stress of exercise, should aim to take in about 20 to 25 grams of glutamine daily divided into smaller doses of about four to five grams each.

Q: Various commercial whey products tout their glutamine content, often referring to "glutamine peptides." Is it possible to take in enough glutamine by using a whey supplement?

A: While glutamine makes up half the body's amino acid pool, whey protein contains about 6 percent peptide-bonded glutamine. So 100 grams of whey protein provide about six grams of glutamine. On the other hand, casein, the other milk protein, naturally contains 8 to 10 percent glutamine. The term peptide-bonded glutamine refers to glutamine that is linked to at least one other amino acid via a peptide bond, or peptide chain. The bonded glutamine is superior to L-glutamine, or free glutamine, because the free form of the amino acid is very unstable in the presence of water, heat and PH changes. The half-life of glutamine in water is comparatively short, which is something to think about the next time you see a drink or protein bar that touts its L-glutamine content. Peptide-bonded glutamine is far more stable than the free-form variety, able to resist such hostile environments as acid and heat. By the way, peptide-bonded amino acids are always better than free form, since free-form amino acids compete with each other for absorption into the body. In contrast, peptide-linked aminos are absorbed by a more orderly and efficient mechanism. Some studies have shown that peptide-bonded glutamine is absorbed as much as 10 times more efficiently than L-glutamine into the body. Some companies use deceitful tactics that make it appear that significant amounts of peptide-bonded glutamine have been added to their product, including claims that a product contains 10 grams of peptide-bonded glutamine. The question you want to ask is, How much of that is actual glutamine? It may be less than you think. Others companies tout a "whey-glutamine-peptide blend." What is that? The glutamine content of whey is so low that a whey-glutamine-peptide blend would be ridiculous, and I'm not even sure the FDA would allow the name to be used. A so-called whey-glutamine-peptide product could never provide the same glutamine content as you get from what's commonly called peptide-bonded glutamine. If you're looking for the latest nutritional superstar, glycomacropeptides, you want to consume whey protein concentrate made from cheese whey, which generally contains far more of that protein fraction than whey protein isolate does. I once had one of the most popular whey protein supplements analysed for protein fractions and found that it contained almost none of the bioactive protein fractions, including glycomacropeptides.

Q: Is hydrolysed whey useless because it's denatured?

A: No. When you hydrolyse whey protein, you permanently modify the native protein structure, meaning that the protein is denatured and so has little or no biological activity. The hydrolysis process breaks apart peptide bonds, which destroys the protein structure. Even so, you still get the amino acids of whey proteins from the hydrolysed whey protein. Half the reason we eat proteins is to get those healthful smaller protein chains.

Q: Does whey protein really help to suppress appetite? A: The glycomacropeptide fraction of whey protein stimulates the release of cholecystokinin (CCK) in the gut. CCK may blunt food consumption while also triggering pancreatic digestive enzyme release and insulin secretion. An important-and often overlooked-point, however, is that glycomacropeptides are found only in cheese whey. What's more, you have to be careful about saying that whey protein helps to suppress appetite. In fact, the human stomach can make glycomacropeptides from casein when it's consumed in its native structure.

Q: Why does casein have a bad reputation compared to whey?

A: Contrary to what some misinformed people have written, casein isn't a bad protein. It is very stable and resistant to PH or heat denaturation when compared to whey proteins. Many people confuse casein with caseinate, which is made by adjusting the PH of acid casein toward a more neutral level by using an alkali. The resultant caseinate is more soluble in water than acid casein and provides a better mouth feel in food products. Casein, in its native micelle structure, however, forms a stable suspension in water and contains a number of biologically active peptide sequences that could be of great value to athletes. Native micellar casein has a different structure from caseinate and is probably used differently by the body. Caseinate isn't cheap; it costs more than a whey protein concentrate. From a nutritional standpoint, caseinate has no drawbacks, contrary to what you may read in whey protein ads. Caseinate is considered to be a high-quality protein source. It's just nonsense to suggest that it will cause gas or indigestion any more than whey or other proteins will. In fact, whey proteins are generally thought to be more allergenic in humans than caseinates.

Q: But isn't whey superior to casein for promoting increased protein synthesis in the body?

A: The study quoted in many current whey protein ads compared the metabolic effects of consuming native structure whey proteins and native structure casein in active, fed subjects. It differs from older studies, which often used fasted subjects, who don't realistically reflect common protein uptake in an athlete's body. The study found that whey protein consumption leads to a rapid but transient increase in plasma amino acids levels and a subsequent stimulation of protein synthesis. It also found, however, that amino acid oxidation was increased and that whey protein had no effect at all on catabolic protein breakdown. The study tells us that when you consume whey protein, it's so rapidly absorbed that much of it is shunted to the liver, where the amino acids are oxidised for energy purposes instead of for synthesising muscle tissue. The rapid uptake of whey does favour increased protein synthesis. The question is, however, How much of the whey protein is used to make muscle tissue and how much is shunted to the liver for oxidation? An important and misrepresented conclusion of this study is the author's own statement that whey provides zero anticatabolic effects in the body. Many people have erroneously interpreted that finding to state that consuming larger amounts of whey protein more frequently throughout the day will provide the same anticatabolic effect as casein did in the study. That isn't what the study showed, though. The author specifically stated that whey protein effected no change in protein breakdown in the body. In contrast, the same study found that casein consumption led to a lower, slower and more prolonged appearance of plasma amino acid levels. The authors even stated that the slower amino acid appearance from casein led to a different metabolic response in the body than that of whey protein. Casein consumption slightly increased protein synthesis, and liver oxidation of casein was moderate compared to whey protein. The important point is that the authors clearly said that casein significantly inhibits catabolic protein breakdown in the body. Even more important, they concluded that casein consumption results in a better net protein balance in the body than you get with whey protein. Unfortunately, there are people in the protein supplement industry who are perverting the results and conclusions of that study to push their marketing agendas. I've read numerous unscientific and invalid interpretations of the study's findings. Instead of being afraid of the effect of the researchers' conclusions on their company's profitability and what it means to their marketing tactics, these people should be educating the industry about the potential benefits for bodybuilders. For example, the study confirmed that whey protein is rapidly absorbed and strongly promotes protein synthesis. At the same time it also found that casein provides a time-released effect and can significantly blunt catabolic protein breakdown. Instead of trying to bend those results or misinterpret them to fit their company's marketing plan, supplement manufacturers should accept the study results at face value. Both whey protein and casein provide beneficial effects. They're absorbed at different rates and elicit different metabolic responses. In reality, they complement each other and should be consumed together for maximum benefit. Recall that mother's milk is roughly 50 percent whey protein and 50 percent casein. Any companies that try to convince you that consuming only whey protein or only casein is the best approach are just blowing smoke. Contrary to what the ads say, there is no scientific basis for their claims. Sure, they can quote many studies, but a closer examination reveals that the studies have little or no applicability in the real world.

Q: Since some studies show increased muscle protein synthesis after exercise, should bodybuilders focus on whey as a postworkout protein source?

A: Look at mother's milk, which is a combination of fast-acting proteins and more prolonged proteins. That takes care of the necessity for rapid protein synthesis while preventing the excess breakdown of newly formed proteins. Fast- and slower-acting protein combinations are the best for any type of growth.

Q: But isn't whey protein richer in anticatabolic branched-chain amino acids?

A: I've had various milk proteins analysed by a major laboratory for their amino acid profiles. After months of lab analysis I found that contrary to popular belief, the different milk-derived proteins don't markedly differ in amino acid content. First, the results of the amino acid assays varied by as much as 25 percent for any individual amino acid, with an average variance of plus or minus 12 percent. It's difficult to say that one protein contains significantly more of an amino acid when the actual results fall within the percentage of variance. A leading manufacturer of whey protein supplements used to print right on its label that its product supplied side branched-chain amino acids at a level of 50 percent of the essential amino acid content of the whey protein. I was interested in that claim, so I compared whey protein, caseinate and a whole-milk protein that contained both whey and casein proteins. I found that the whey protein concentrate supplied an average of 49.5 percent of its essential amino acids as side branched-chain aminos. The caseinate also showed an average side branched-chain amino content of 49.5 percent. The milk protein averaged 49.3 percent. Those results may explain why the company that sold that leading whey protein supplement removed the ridiculous text from its label.

Q: What about combination protein supplements, such as milk, egg and soy?

A: I don't think that soy protein offers benefits for bodybuilders. For example, unlike casein, it doesn't form a good curd in the stomach, which makes it a fast protein. Also, the amino acid pattern in soy is inferior to that of milk proteins and not as favourable for promoting growth. Egg albumin is similar to the lactalbumin found in milk. The problem with egg protein is that it's highly allergenic, but if you can tolerate it, it's a good protein. If you look at this issue in terms of survival, it would be a good idea to combine various proteins, including soy. For promoting maximum muscle growth, however, milk proteins are best. That's reflected in a measure of how efficiently protein stimulates growth, which is called the protein efficiency ratio (PER). The currently accepted PER for soy is 1.7 to 1.8. It started out as 1.2, but the PER testing method was modified over a period of years so that soy protein scored better on the test. The result is that soy protein now has an accepted PER of 1.8. For casein it's 2.5.

Q: How accurate are the labels on most current commercial protein supplements?

A: Not very accurate. Most labels misstate the powder contents. That would particularly apply to the protein fractions discussed above; take, for instance, glycomacropeptide, which is a hydrolysed piece of kappa casein. Manufacturers add hydrolysed whey proteins to their supplements. The hydrolysed whey protein may contain pieces of whey peptides that are in the same molecular size range as glycomacropeptides and may even show up on analysis as them, yet they aren't glycomacropeptides. Despite that fact, the protein supplement labels state that they contain a certain amount of glycomacropeptides. Such labels are probably misleading because it would be very hard to guarantee a specific glycomacropeptide content from any current protein source. Also, remember that a true ion-exchange whey protein isolate contains no glycolmacropeptides.

Q: What is the ingredient found in some products that's called "complete milk protein"?

A: Complete milk protein is a whole milk protein that is separated from the other constituents of cow's milk by a filtration process. Since no PH changes or excessive heat are used in the processing, the protein retains more of the biologically active protein fractions that are limiting in other protein sources. The casein and whey are in their native, undenatured structures. This is simply protein the way nature intended. The best combination probably involves a filtered milk protein with whey protein concentrate, since you get all the bioactive protein fractions plus both rapid and extended protein activity in the body. The scenario favours increased protein synthesis and a significant anti-catabolic effect.