Saturday, August 1, 2009
Egg White Protein
what is it ? Eggs - in particular egg whites - have been a staple protein source for body- builders and other athletes for decades. Egg white, or albumen,: ovalbumin (54%) conalbumin (13%) ovomucoid (11%) globulins (8%) lysozyme (3.5%) ovomucin (1.5%) other proteins present at <1%:>
Supplemental egg white protein is sold as a spray-dried powder, or in liq-
uid, pasteurized form.
What is it supposed to do?
Egg white protein is a virtually fat-free, low-calorie source of protein. While
egg white proteins are not - as far as is currently known - a source of bioac-
tive peptides (such as whey, etc.), they can be used to increase the overall
protein content of the diet.
What does the research say?
Beyond serving as a source of protein, there is little that’s special about egg
whites. Substituting egg white protein in the diets of hypercholesterolemic
women had bene cial e ects on serum lipids. Egg white is also relatively
high in BCAAs, so can be used in addition to other protein supplements
such as whey as a source of these critical amino acids.
There is a myth, pushed by various “raw food” fanatics, that eating dena-
tured proteins is somehow harmful and/or unhealthful. While most people
wouldn’t eat raw meat, they nonetheless will consume raw eggs, in the
belief that cooking “destroys” the protein, or makes it less digestible.
But the precise opposite is true for egg whites. Research has shown that
raw egg whites, in fact, are much more poorly absorbed than cooked ones.
In two separate studies, raw egg whites consumed by human volunteers
were 35% - 50% undigested and absorbed, whereas only 5% - 9% of cooked
egg whites were not assimilated.
The liquid egg whites sold refrigerated have been pasteurized. I’ve been
asked if these whites are more digestible than fresh, raw whites. They
probably are, but I doubt that they are as digestible as completely cooked
whites.
What does the real world have to say?
Many bodybuilders supplement their protein intake with egg whites: both
cooked or blended with other proteins in a shake. It’s a simple and conve-
nient way to add extra protein, which is why it’s such a common practice.
Recommendations:
It should be emphasized that egg whites aren’t good for much else besides
protein. Most of the egg nutrients are contained in the yolk. So while egg
whites can be used to boost the protein content of a meal, they shouldn’t
be used to replace more nutritious sources.
Another point of contention regarding egg whites is people are under the
impression (often due to misleading marketing by companies selling egg
white protein) that egg whites are some sort of super protein. It should be
noted the high score eggs have is based on the whole egg only. For ex-
ample, whole eggs score 100 on the biological value (BV) protein scoring
system. Egg whites have a BV score of 88. 88 is not a low quality protein
per se, but it’s not the BV of 100 whole eggs enjoy. Will this have any nega-
tive e ects on your ability to gain LBM? Unlikely, but when ever you see
companies calling their egg white protein product “natures perfect food”
or “the gold standard protein” and other over hyped nonsense,
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