There’s been much talk lately about protein from Goat whey. We’ve all heard the marketing claims - highest bioavailability of any protein on the planet, more easily and rapidly absorbed because the molecules are smaller, hypoallergenic, highest in BCAA’s and a Biological Value of 104. Are these claims really true? Just how does goat whey protein stack up to bovine whey protein?

First let’s take a look at the claims of Protein Quality. Is goat whey protein more bioavailable than bovine whey protein? Is it really the highest bioavailability of any protein on the planet? The marketers of goat whey protein continually shout that their protein has a biological value of 104. What does biological value mean? Well, in its simplest form, biological value is a value that measures how well the body can absorb and utilize a protein. The higher the Biological Value (BV) of the protein, the more your body can absorb, use, and retain. Scientists trace protein nitrogen as it enters the body through eating. They then measure the amount of protein nitrogen that is retained in the body versus the amount of protein nitrogen that is expelled from the body through urine and feces. The more protein nitrogen that is retained indicates a higher degree of bioavailability of that protein. Conversely, the more protein nitrogen that is excreted as urine or fecal matter, the less the bioavailability of that protein. Obviously, BV is really just a mathematical value - a result of dividing the amount of nitrogen retained in the body by the amount of nitrogen consumed and multiplying that result by 100. For example, if one consumes 100 grams of protein per day and retains 80 grams of protein in the body (as measured by finding that 20 grams of nitrogen was excreted in urine and feces), then that protein has a BV of 80. It’s very easy to figure out that the highest BV attainable is 100 - indicating complete utilization of the protein that is consumed.

Scientists at one time thought that egg white had the highest protein BV. Studies usually showed a result of 100 for egg protein. Then, studies began to find an even higher result for bovine whey protein - a BV of 104. How can one obtain a result above 100? Well, it has to do with experimental error and possibly even fooling around with the testing procedures. Many of you will recall those foolish whey protein marketers who tried to fool us with claims of a BV for their whey protein of 157. Obviously, such a result is way off mathematically and is not just due to experimental error. Such results come about because the studies were designed in a biased fashion to dramatically improve the BV of protein and then the results were skewed in such a way that the final result was mathematically impossible. BV results can be significantly increased by having the study participants fast for days before the study begins or by feeding the subjects very small portions of protein during the study - BV values drop as protein consumption per dose increases. For example, milk protein, when administered in meals at intakes of 0.2 grams per Kg of body weight, shows a BV of 100. However, when one increases milk protein intake to 0.5 grams per Kg of body weight, the BV result drops to 70. This phenomenon happens with all proteins and must be taken into account when one measures protein value by BV. Nevertheless, the best BV ever reported for goat whey protein is 104. The lowest BV ever reported for bovine whey protein is 104 and the highest is 157. Which whey protein appears to be superior in bioavailability? According to BV, it is bovine whey protein.

What about the claim that goat whey protein is more easily and rapidly absorbed than bovine whey protein? Goat whey protein molecules are slightly smaller in molecular size than bovine whey protein molecules. They are only slightly smaller, however, and perhaps not significantly smaller so as to result in a significant difference in absorption rate.  As a general rule, smaller protein molecules will digest faster and absorb faster into the body. That is why bovine whey proteins are called fast digesting proteins and casein is called a slow digesting protein. But let me ask you this … what good is fast absorption? Have you ever seen a study that clearly outlined why fast absorption of proteins is good for you? It’s easy to say, “Our protein will absorb faster”, but what does that mean for your metabolism or your muscles? In actual fact, not much. The body needs both fast and slow proteins for optimal gains. Further, we just finished looking at the comparative Biological Values of bovine whey protein and goat whey protein. The BV values reflect how much of the whey proteins were absorbed. Bovine whey protein has at least the BV of goat whey protein (and probably higher), so doesn’t that mean that bovine whey protein is absorbed as well as goat whey protein and perhaps even more easily absorbed? By my reckonings it does! To further illustrate that point, one leading goat whey marketer proudly claims in their ads that goat whey protein is more easily and rapidly absorbed, with a BV of 104. In the next paragraph, however, they state that “goat whey has a nearly 94% absorption rate”. How can one have a BV of 104 if only 94% of the protein is being absorbed? Answer: You can’t!

What about the claim that goat whey protein is hypoallergenic, unlike that highly allergenic bovine whey protein? Let’s get one thing straight - goat milk is less allergenic than bovine milk. That statement does not translate over to whey proteins. Cow’s milk contains an allergenic protein, alpha S-1, that is not found in goat milk. Sometimes human infants, and even more rarely, human adults will be lacking the enzyme to tolerate alpha S-1. They have an allergic reaction to the small protein. When that allergic reaction occurs, infants are switched to goat milk which lacks alpha S-1. From that simple difference, goat milk has gained legendary status as being hypoallergenic. In actual fact, usually humans will outgrow the intolerance of alpha S-1 and they can drink bovine milk just fine after a certain age. The question to be asked is, Is there a difference in allergenic reactions between goat whey protein and bovine whey protein? The definitive study was performed a long time ago in 1939 when Hill et al reported that children who exhibited positive skin reactions to bovine whey protein also exhibited the same positive skin reactions to goat whey protein - they were identical in their allergenic strength. In 1983, Juntunen and Ali-Yrkko found that children who were intolerant to bovine milk protein were also intolerant to goat milk protein. While there may be a difference in toleration of the two milks, the claim of different allergenic qualities of the proteins are false. Don’t let anyone fool you -goat whey protein has been shown to be similar to bovine whey protein in allergic reactions.

What about goat whey protein being higher in essential amino acids and higher in the BCAA’s (branched chain amino acids) than bovine whey protein? Let’s look at typical amino acid profiles for both whey proteins.

Essential Amino Acids

Grams Amino Acids per 100 Grams of Protein.

                                                 Bovine Whey           Goat Whey

Isoleucine                                           7.8                        4.8

Leucine                                             10.2                        9.4

Lysine                                                9.1                        6.4

Cysteine & Methionine                         3.8                         3.4

Phenylalanine                                     3.1                         4.4

Serine                                                5.2                        5.4

Tryptophan                                         1.7                        1.0

Valine                                                6.0                        7.1

From this comparison of essential amino acids contents, we can see that bovine whey protein contains 46.9 grams of essential amino acids per 100 grams of protein while goat whey protein contains 41.9 grams of essential amino acids. As far as the BCAA’s (leucine, isoleucine, and valine), bovine whey contains 24 grams of BCAA’s per 100 grams of protein while goat whey contains 21.3 grams of BCAA’s per 100 grams of protein. You be the judge. Which whey protein has the higher BCAA content? Which whey protein has a higher essential amino acid content? The answer to both, of course, is bovine whey protein.

Is goat whey protein better than bovine whey protein? The answer is a resounding, NO! Don’t get taken in by marketing hype and untrue statements. Look at the facts for yourself. The simple facts are that cows produce much larger quantities of milk than goats. That means that bovine whey protein will always be in more plentiful supply than goat whey protein and, by the laws of supply and demand, will be less expensive than goat whey protein. Save your money! Stick with bovine whey protein. At the very least, it is every bit as good for you as goat whey protein and appears, as it turns out, that it might just be of more nutritive value than goat protein.