Types of Protein

TYPES OF PROTEIN USED IN PROTEIN SUPPLEMENTS:


WHEY PROTEIN
Whey protein, which is derived from milk, is by far the most popular protein on the market. Whey protein comes in various forms like "whey concentrate" and the better, more pure "whey isolate" form. Whey protein concentrate is a lower grade whey protein that does not provide the benefits of microfractions and is usually higher in fat and lactose. 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 absorbed protein (aka anabolic).

There are some advanced procedures (like cross flow microfiltration) that lead to a higher quality whey with added benefits over ion-exchange whey isolate in preserving key microfractions which are essential to it’s benefits. Whey protein isolate that is not heat treated contains these 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! Most of the whey protein on the market is usually found as ion-exchange (a process where electric charges are used to extract the protein). Some users of whey protein concentrate may experience bloating or gas due to its lower quality but it is very cost effective.

BENEFITS: Whey protein is more rapidly absorbed than other proteins. Quality whey protein isolate provides key microfractions discussed previously, has a very high concentration of BCAA’s (branched chain amino acids) which can positively effect lean muscle mass and lower muscle breakdown (whey protein contains about 25% BCAA’s—the highest of any protein source), enhances glutathione levels in the body (glutathione is the body’s most powerful natural anti-oxidant 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. Very high protein efficiency ratio (PER) and Biological Value (BV).

DOWNSIDE: Whey protein is lower in natural glutamine and arginine content, is less filling than other more slower absorbed proteins, and quality whey protein isolate with preserved microfractions is a bit pricier than other proteins.

BEST USES: Due to its quick absorption, whey protein is excellent to take before or even right after a hard workout. It also works as a between meal snack for a protein boost in the middle of the day.



CASEIN PROTEIN
Casein protein is manufactured and derived from fresh skim milk. Casein protein is extracted from casein through acidification, which in turn, provides the user with a slow digesting protein. This slow digesting time leads to “anti-catabolic” or “protein sparing” properties and gives the user a feeling of being fuller longer.

Casein is also a milk derived protein and comes in various forms including calcium caseinate, sodium caseinate, and micellar casein. Casein has a reputation for being the “anti-catabolic” protein and has some advantages over whey. NOTE: Protein catabolism is the breakdown of proteins into amino acids and simple derivative compounds, for transport into the cell through the plasma membrane.

First, casein is absorbed more slowly and can provide a sustained release of amino acids into the blood stream over a longer period of time. It forms a gel in the stomach and the amino acids are extracted more slowly and may be better absorbed over the long run.

There are a few good studies that confirm the benefits of casein protein over whey protein including the famous Boire study which showed casein’s powerful ability to reduce muscle breakdown and increase protein synthesis and a more recent study in police officers which showed that the special casein group lost more body fat, gained more lean muscle mass, and had greater strength increases than the whey protein group. The authors of the study attributed it to the anti-catabolic effects of the peptides (chains of amino acids) found naturally in casein. Peptides are absorbed better than amino acids due to peptide transport systems in the gut. “Casein is definitely making a comeback due to its anti-catabolic and hunger reducing effects” says Andrich.

Casein protein is used as a dietary supplement by bodybuilders, athletes and dieters who ingest it before bed, or with breakfast, instead of after working out, as it breaks down at a slower rate than whey protein, thus supplying the body with a sustained protein release.

BENEFITS: It is more slowly absorbed, creating a greater sense of “fullness”. Also, there is a longer release of amino acids into the bloodstream and it has a very high glutamine content (especially in the better absorbed peptide form). Micellar casein which is undenatured (not heat treated) contains some milk fractions which can boost immune function and increase growth factors in the body.

DOWNSIDES: Casein does have a higher lactose and sodium content so water retention and some stomach discomfort could result.

BEST USES: As a pre-bed time drink to lower muscle breakdown during sleep or for breakfast to provide a steady stream of amino acids in the morning.



SOY PROTEIN
Isolated soy protein, a plant protein derived from soy beans, has been the subject of many research studies and seems to be in the news a lot. It is a good protein source that has many positive health effects along with benefits to athletes.

BENEFITS: It has a good amount of key amino acids including glutamine, arginine, and the BCAA’s, it may boost metabolism by enhancing natural thyroid hormone levels, it contains isoflavones which have been implicated in lowering cholesterol and triglycerides, and it is a lower costing source of protein.

DOWNSIDES: Some people complain about the taste of soy products and lower quality soy protein does contain small amounts of phytoestrogens which would be detrimental to men.



EGG ALBUMIN PROTEIN
Nutritionists commonly refer to eggs as the "Golden Standard" for protein quality. Eggs contain all of the eight essential amino acids (the type that your body cannot make from other substances) and very high levels of total amino acids - especially important sulfur-containing aminos. Eggs are also readily digested and absorbed. As a lactose-free protein source, eggs are often more tolerable to people who have trouble with dairy foods. For these and other reasons, eggs have been a staple of bodybuilder’s diets since the beginning of the sport.

Egg protein, the “oldest protein” has been used by athletes around the world for many years. Before the products below were created, bodybuilders were forced to drink egg whites, which can be unsafe, or cook dozens of eggs at a time. The high cholesterol and fat in eggs made this a somewhat unhealthy way of getting your protein. Now, the introduction of egg protein products have fixed many of these problems.



HYDROLYZED COLLAGEN PROTEIN
Hydrolyzed collagen protein is also known as gelatin. Collagen is the chief structural protein that makes up connective tissues in the body such as skin, bones, cartilage, tendons, and ligaments.

Hydrolyzed collagen protein is simply a modified form of the protein that has been broken down into smaller pieces by enzymes. This makes the protein easier to incorporate into dietary products and may ease the digestion and absorption of the amino acids by the intestine.

Hydrolyzed collagen protein is not a complete protein source as it does not contain all essential amino acids. It is low in the sulfur containing amino acids such as cystine (cysteine) and methionine. However, Hydrolyzed collagen protein is the richest dietary source of the primary amino acids that make up the collagen molecule – glycine, proline, hydroxyproline, lysine and hydroxylysine.

Hydrolyzed collagen protein is often used as a general protein source in body building products because it is relatively inexpensive. Hydrolyzed collagen protein has most recently been used to promote joint health, provide nourishment to cartilage and bones and help athletes recover from exercise and sports-related injuries.



PROTEIN CONTENT OF FOODS
A number of our common, everyday foods are good sources of animal and plant protein.
Check out our list of high protein foods.


How do I know if my protein supplement is being absorbed appropriately?

This is a very complicated and highly debated issue. There are essentially 4 different scales (at least) for assessing protein bioavailability:

1. PER – protein efficiency ratio (gain in body weight/weight of protein consumed)
2. NPU – net protein utilization (reflects percentages of a food protein retained)
3. BV – biological value (amount of protein deposited per gram of protein absorbed)
4. PDCAAS – protein digestibility corrected amino acids score (Currently recognized as the most important measurement method. Compares the quality of various proteins based on the amino acid requirements of humans)

Here are some examples:

BV of select protein sources:
- Egg 93.7
- Milk, 84.5
- Fish, 76.0
- Beef, 74.3
- Soybeans, 72.8
- Rice, polished 64.0
- Wheat, whole 64.0
- Corn, 60.0
- Beans, dry 58.0


PER of select proteins:
- Whey Protein, 3.6
- Milk Protein, 3.1
- Casein, 2.9
- Soy Protein, 2.1


PDCAAS of select proteins:
- Soy, 1.00
- Whey, 1.00
- Egg, 1.00
- Beef, 0.92
- Pea, 0.73
- Oats, 0.57
- Peanut, 0.52
- Rice, 0.47
- Corn, 0.42
- Wheat Gluten, 0.25


NPU of select protein sources:
- Eggs, 94%
- Milk, 82%
- Brown Rice, 70%
- Meats (most), 65-57%
- Soybeans (alone), 61%
- Legumes (alone), 50-60%
- Whole Grains, 50-60%

To asses any individual protein source, you have to know each number for each protein and sort of weigh out the benefits. Egg tends to get the highest overall scores, followed by dairy proteins (whey, casein and milk), and followed closely by soy and fish.