Protein is your most metabolic active tissue, which means, the more muscle mass you have, the more potential you have to burn fat. I have recently been asked a number of questions about the differences and the value of certain types of protein. Although food is always a first preference for protein rebuild and recovery, protein supplements also provide the building blocks for muscle growth. Hopefully this article can uncover some mysteries behind the types of protein supplements on the market, when and how much to use of which (including real food), and if there is a real difference to the value of each.
Protein supplements are relatively inexpensive and are convenient. This leaves me with one warning: Make sure you that you are only supplementing protein as needed, do not overdose on protein, and do not rely entirely on supplementation.
The most common protein supplements are whey, egg, soy and casein. All four of these protein supplements have different characteristics and are used differently depending on what you’re trying to achieve. There are several different methods used to evaluate the quality of proteins. These include Protein Digestibility Corrected Amino Acid Score (PDCAAS) measuring quality based on amino acid requirements , Biological Value (BV) based on the bioavalibilty, or absorption quality of the protein, and Protein Efficiency Ratio (PER), which is the ability of the protein to support growth.
WHEY
Whey is a preferred source right after a workout because it is digested relatively fast, enhancing the recovery function quickly. It is a milk protein (meaning that it is isolated into a powder form from milk). It is also a complete protein, meaning that it includes all essential amino acids. Amino acids are the building blocks of protein, and as these connect together, they form whole proteins. Essential amino acids means that the body is unable to form these unless there is an eaten source of it. Whey also contains what we call Branch Chain Amino Acids (BCAA) – These are a group of 3 of the essential amino acids, that in combination, make up over a third of all muscle mass in human physiology. They have also been hypothesized to enhance muscle growth in supplemental form.
Whey protein tends to score the highest in quality protein. Many supplement companies highlight PDCAA scores on the labels of their protein products. As a professional in the field, I would recommend that you not obsess about the PDCAA scores, rather concern yourself with the ingredient list. If there are ingredients that are not natural, such as artificial flavors/sweeteners, or chemical words that you could not pronounce or spell yourself, take that as a red flag for lower end quaity. Supplements should provide as clean a product as possible, and not contain any unnecessary or artificial ingredients.
Whey in a nutshell – well not really! To further complicate this topic, whey comes in different types: whey protein concentrate, whey protein isolate and hydrolyzed whey protein. Whey protein concentrate is the most commonly used source of protein and also the most economical. Hydrolyzed whey protein is the least common and most expensive (a protein typically used by hardcore bodybuilders) and whey protein isolates are a combination of the two.
EGG
Egg protein was the protein of choice for athletes back in the day. Remember Rocky drinking raw eggs? Many athletes still hold onto the value of egg protein today because it is considered the gold standard for protein quality. According to the BV scores, egg protein is a perfect 100. This stems from all of the protein in an egg is used by the body and its readily digested and absorbed. Egg protein is also a lactose-free protein source. Egg protein has all the essential amino acids the body needs and high levels of total amino acids especially important sulfur-containing amino acids which are essential to various hormonal pathways in the body.
You can obtain whole egg protein two ways eating egg or an egg protein powder supplement. Both of these methods will supply all the essential amino acids in a bioavailable way, but is more caloric dense and higher in fat than the other protein sources. (One way to obtain egg protein yet combat calories from fat, is to separate the egg whites from the yolks, and only consume the whites. The yolks are what contain the extra fat and thus calories – however, supplemental egg protein will not have separated the fat).
SOY
Soy protein is the only source of amino acids that is from plants and not animals. Other than vegetarians, the athletic and power building networks give soy a bad rap. Soy protein has the least biological value (BV) score. A reason soy is so low on the BV scale it lacks the sulfur containing amino acid methionine, which is particularly important for protein synthesis.
Several studies have shown soy protein to be inferior to whey for the production of glutathione, an essential nutrient for growth and improvements in immunity. Furthermore, Soy protein contains “anti -nutrients” meaning that it blocks the digestion and absorption of many nutrients. Finally, soy is rich in estrogenic compounds such as genistein and diadzein, which means it may also have a tendency to compete for estrogen receptor sites, a negative physiological pathway. There are over 300 plant derived phytoestrogens found that vary substantially in their physiologic effect and potency in animals and man. Not only in athletes, changes in the testosterone/estrogen ratio can lead to increased body fat and other ill effects.
So why then would a company even want to deal with creating and marketing a soy based protein. For one thing, it is the only complete protein available to vegans and vegetarians. Many of the manufacturers have also removed anti-nutrients to create a higher quality of soy protein in supplemental form. Many manafacturers have also added in Glutathione to improve the Biological Value overall. Another upside, is that Soy appears to have several mechanisms to lowers cholesterol (i.e. isoflavones, endocrine effects, and fiber). In addition to soy proteins ability to reduce cholesterol, epidemiological research also suggests soy can reduce certain forms of cancer.
The intake of various high quality proteins has been associated with higher levels of thyroid hormone. Research has shown that soy appears to have thyroid hormone raising abilities over and above that of all other proteins. Some studies have also found changes in the insulin/glucagon ratio that would favor reductions in cholesterol and possibly body fat. At this time, exactly how soy proteins have this effect on thyroid output is not well understood. Based on the research with such conclusions, one can thus hypothesize that although thyroid hormones are considered catabolic hormones, they actually break down more fat and carbohydrates, and stimulate protein synthesis if adequate calories are eaten and the amounts of thyroid hormones are in normal range. In the media today, you will find both positive and negative reasons to acquire soy protein in our diets, however, more research is needed in this area, for any definitive conclusions. My overall recommendation is go with the higher value proteins (animal sources) unless you are vegan or vegetarian.
CAESIN
Casein, like whey, is a milk protein. It makes up 80% of the protein in cows milk, and the remaining 20% of protein in milk is whey. Casein protein is extracted from the milk through ultra filtration, without the use of chemicals. Thus Casein tends to have more bioactive milk peptides that support immune function as whey, and it also enhances muscle growth. The difference between whey and casein is the rate of digestibility. Casein is a slow-digesting protein. It’s often referred to as the “7-hour” protein because it can take as long as 7 hours or more for the body to fully digest it. Whey on the other hand, is a fast-digesting protein. Hydrolyzed whey, for example, can be digested as quickly as 45 minutes.
Casein is therefore primarily used at night for slower progressive recovery. Whey, on the other hand, is usually used right after a workout.
In Summary:
While all these proteins are different in their quality, bioavailabilty, and rate of digestion, they have two things in common: they help build lean muscle and aid in losing weight. By getting protein from a variety of sources, you will get a wider amino acid spectrum and you will supply your body with a steady supply of amino acids.
BV of common proteins
