Why Whey is the Way to Go
Protein is one of the most important
food components for the human body. If your diet is low in protein, you’re
in big trouble, and if you’re a bodybuilder who is not taking in adequate
amounts of protein, you’re doomed. Proteins have many unique properties and
can be found in every tissue and cell of the body. They contain amino acids,
which are essential for cellular growth and repair and the synthesis of DNA
and RNA. These building blocks of protein provide the chemical backbone for
a large number of enzymes and hormones as well.
Although some of my physician and scientific colleagues still debate
the amount of protein that an athlete should have in his or her diet, take
it from me: If you are a bodybuilder, weight lifter or any serious,
hard-training athlete for that matter, you need a lot of protein. But there
is another important distinction to be made: the source of your protein.
They're Not All Alike
There are many protein supplements on the market. Most are egg- or
milk-based, while others are made from soy, beef and even gelatin sources.
Due to their ready availability and low price point, the majority of protein
supplements over the years have been milk proteins.
Raw milk is the starting point for the manufacture of a host of milk
products. Although it contains a number of different proteins, milk contains
two major proteins that are used in the dietary supplement industry: casein
and whey.
Casein is the principal protein in milk, and until fairly recently, the
most commonly used milk-protein derivative. Food scientists add the enzyme
rennin to milk to precipitate the casein. Casein has a biological value of
77, which means that your body will absorb 77% of the available protein.
Whey protein is also derived from milk. (Remember the nursery rhyme
about Miss Muffet and her curds and whey?) Amazingly, this byproduct of the
cheese industry used to be discarded. In contrast to casein’s biological
value of 77, the biological value of whey approaches 100. Hence, when
compared to casein, whey easily wins. Whey protein is also rich in
tissue-regenerating substances like branched-chain amino acids, cysteine,
minerals and lactalbumin.
The higher-quality whey-protein products use ion exchange and
microfiltration to remove microbes and other impurities, allowing for a
purer product. These filtration processes allow for the removal of most of
the lactose in whey supplements, but scientists have yet to achieve a
completely lactose-free product (something to keep in mind if you are
lactose-intolerant). Whey commonly comes in powder form as a “concentrate”
or “isolate.” The concentrate has up to about 80% whey, of which 6 to 8% is
lactose. (The remaining 20% is moisture.) Whey isolate can be concentrated
to as high as 93% purity with only 1 to 1.5% lactose.
Selecting whey isolates guarantees that heat processing has been minimized, while assuring that the product is safe.
Immune-Enhancing Properties
Whey protein has unique immune-enhancing attributes. In one study with
rats, a whey-protein diet enhanced the liver and cardiac concentrations of
the antioxidant glutathione (GSH). Cellular glutathione levels are
diminished by strenuous physical activity. Suboptimal levels of cellular GSH
have also been found to alter the structural and functional integrity of
muscle. Whey protein is approximately 2.5% cysteine, which has been shown to
increase intracellular GSH levels.
Glutathione is also necessary for lymphocyte proliferation in the
development of a vigorous immune response. The amino acid cystine (which is
reduced to cysteine once it enters the cell) aids in the coordinated
response of macrophages (special white blood cells) and lymphocytes. This
response is regulated in part by cystine uptake in the macrophages and
lymphocytes. In turn, this aids in decreasing the amount of oxidative damage
that results from strenuous physical activity.
By consuming whey, you help to avoid cellular GSH depletion. It is
therefore conceivable that whey protein can also promote recovery and stave
off overtraining syndrome in the high- performance athlete (something that
bodybuilders and fitness enthusiasts slip into all too often).
Whey isolate can be concentrated to as high as 93% purity with only 1 to 1.5% lactose.
The Advantages of Whey-Protein
Isolate
Whey-protein isolate is a superior form of whey protein because of its
purity, high GSH content, increased bioavailability, solubility, relatively
low lactose content and high concentration of branched-chain amino acids.
The method of pasteurization also has an effect on protein
availability. All proteins are sensitive to heat, and since pasteurizing
involves heat, you should factor this in when you are selecting a whey
product. The methods of protein processing that are legal in the United
States include high-temperature, short-time pasteurization (in which milk is
treated at 72 degrees Celsius for 15 seconds); low- temperature,
long-duration (in which milk is treated at 62 degrees Celsius for 30
minutes); and ultrahigh temperature pasteurization (in which the milk is
treated at approximately 77 degrees Celsius for a few seconds). The method
known as cold-filtration pasteurization, which minimizes heat exposure,
yields the most intact protein product. How-ever, cold filtration is illegal
in the United States because it is believed that the bacterial pathogens may
not be killed.
Whey-protein isolate has the most science to back it. Whey-protein
hydrolysate is sometimes found on the market, but don’t be fooled.
Hydrolysate is an inferior protein due to the denaturation that occurs
during excessive heating. The bottom line is this: As long as you go with a
brand name you can trust, selecting whey isolate guarantees that the heat
processing has been minimized, while assuring that the product is safe to
consume.
Perhaps the reason that other forms of whey still can be found on the
market is pricing. Although isolates are superior to other forms, this
superiority is unfortunately reflected in the price. Isolates can cost two
or even three times more than concentrates and hydrolysates. Many companies
combine these forms in their products, so you can get a blend of whey at a
more affordable price. I have no objection to this and find it quite
reasonable. However, during the precontest period and while you are ill or
training heavily, you should use whey isolate if your wallet can handle it.
As far as bioavailability and absorption are concerned, again my
preference is for the isolate, followed by whey-protein concentrate and then
by whey-protein peptides. Some whey protein isolates are more than 90%
soluble and up to 98% bioavailable. This makes them a superior form of
whey-protein supplementation.
Making the Best Choice
You need to keep abreast of the facts so you can make educated purchasing
decisions. Considerable research supports the use of whey protein. It has
been touted as the most powerful protein antioxidant because of its unique
actions at the cellular level. Whey has also been shown to be a positive
immunomodulator that can even increase the life span of animals. Perhaps
most importantly for the athlete, whey protein has the highest biological
value of any available protein.
As the verified benefits of whey protein continue to grow, the
popularity of this amazing supplement will continue to increase. So, as both
a practicing physician and former bodybuilder, I believe that you should
strongly consider adding whey to your supplement regimen in case you haven’t
already done so. Pay attention to labels to ensure that you are getting a
high-quality product, and try to get as much whey-protein isolate as
possible. Its many proven benefits clearly make it the best type of whey for
you.
Selected References: Giese, J “Proteins as ingredients: Types, functions and applications” Food Technology (1994) Oct: 50-60 Boza, JJ, Jimenez, J, Martinez, O et al “Nutritional value and antigenicity of two milk protein hydrolysates in rats and guinea pigs” Journal of Nutrition (1994) 124: 1978-1986 Bounous, G and Gold, P “The biological activity of undenatured dietary whey protein: Role of glutathione” Clinical and Investigative Medicine (1991) 14: 296-309 Bounous, G, Batist, G and Gold, P “Immunoenhancing property of dietary whey protein in mice: Role of glutathione” Clinical and Investigative Medicine (1989) 12: 154-161 Sastre, J, Asensi, M, Gasco, E et al “Exhaustive physical exercise causes oxidation of glutathione status in blood: Prevention by antioxidant administration” American Journal of Physiology (1992) 262: R992-R995 Batterman, W “Whey protein for athletes” Deutsch Milchwirtschaft (1986) 37: 1010-1012
