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WHAT IS CASEIN?
Caseinate makes up about 80% of the protein of milk, sweet dairy whey
comprising the other 20%. Casein is a relatively cheap form of protein of which
there is a high abundance of from the milk processing industry. During cheese
manufacture, casein, is the curds portion of the curds and whey. Calcium
caseinate is the most common name for casein and is often used in the
manufacture of meal replacement powders, sports protein bars and baby milk
formulas. As a protein it has a relatively low biological value of 77, about
half that of a good whey protein as it does not contain all of amino acids
required for proper human metabolism. Casein is the main source of protein in
cows milk whereas whey is the main source of protein in human milk. Casein is
often found in pre mixed drinks and sports bars as it is much easier to make a
good tasting, soft and fluffy bar with this type of protein than most others and
for the manufacturer can keep the cost relatively low.
DIGESTING CASEIN
Casein can take upto 7 hours to digest fully. When ingested, casein clots in
the stomach forming a thick cottage cheese consistency rather than remaining as
a liquid. For some, casein can actually cause stomach upsets, wind, bloating and
puffy skin and has been shown to be the main allergen in cows milk. Since of
course cows milk was designed by nature to be drank by baby cows and not adult
humans (human mothers milk is very different in make-up to cows milk) many
adults lack the enzyme lactase to digest the high lactose levels. The term
lactose intolerance applies to much of the population without ever actually
realising the cause of there stomach upsets, headaches and other ailments. Some
research has shown that blood groups O and A should avoid casein altogether,
whereas blood groups B and AB can tolerate it much better. Not all of this
research is fully conclusive and has been linked to other foods being
intolerated by certain blood groups. It is probably best to avoid all foods that
cause any stomach problems. There has also been
some research linking casein to elevated cholesterol levels and colon cancer.
POSITIVE BENEFITS OF CASEIN
There is however, a growing popularity for casein to be used these days as
there have been some positive benefits noted from it's use. Mainly that the slow
absorption rate can be used advantageously. Rather than taking a protein like
whey into the system, say before bed, when our bodies are restricted of protein
for quite some time while we sleep, taking casein will slowly release amino
acids into the blood stream as it is being digested, possibly over a full 7
hours. This slow release of amino acids can cause a very favourable
anti-catabolic state (preventing muscle tissue from breaking down).
Theoretically whey would be a better protein for muscle anabolism, however,
arguably studies have shown that the fast influx of amino's from whey cause a
high anabolic response very fast (muscle building) with no anti-catabolic
properties and a high increase in oxidation rate creating a steady state
nmetabolism and no overall increase in protein balance. As a good basis for
hypothesis combining both whey and casein in a sensible ratio would provide the
positive benefits from both of these proteins. In all honesty many people are
already doing this without actually realising. They mix 25 - 30g of good quality
whey protein with about a glass to a pint of milk and have created a drink with
an extra 8 - 16 g of slower acting casein. Where whey lacks the amino acid
phenylalanine, casein is rich, and where casein lacks BCAA's, whey is rich,
making a very good combination. Milk however does contain lactose, a form of
sugar, and is a pretty good form of actually increasing body fat levels. A
better choice of casein would be cottage cheese which is nearly all casein,
naturally high in glutamine and relatively low in lactose compared to milk.
Casein comprises 20.5 % glutamine, higher than whey, soy or egg proteins,
especially in the peptide form. This can seriously help spare muscle mass during
intense training or periods of dieting. One drawback of cottage cheese, along
with many other casein products, is the lactose for one and the naturally
occuring high levels of sodium.
CASEIN AND AMINO ACIDS
Interesting to note that casein contains a 5:1 ratio of tyrosine to
tryptophan and could be considered to be one of the highest 'stimulating'
proteins available. Tyrosine is an amino acid that signals the brain to be awake
and alert whereas tryptophan signals the brain to sleep. Consuming enough of a
dose of casein could supply the brain with an increase in excitatory
neurotransmitter levels, giving a noticable boost.
CASEIN AND GLUCOSE PRODUCTION
Casein also boasts a high proportion of glucogenic aminos, which include
threonine, glutamine, and arginine. The glucogenic aminos lend themselves to
glucose production for energy during exercise and have been shown to possibly
help defer muscle breakdown. Large doses of glucogenic aminos have also been
shown to increase feed efficiency in animals meaning it could be possible to eat
less and build more muscle.
PROCESSING OF CASEIN PROTEIN POWDERS
Calcium, potassium and sodium caseinate are inert proteins - pH adjustment
and heat processing have rendered their fractions inactive. The fractions being
Alpha-Lactalbumin, Beta-Lactalbumin, IgG Heavy (immunoglobulins), BSA (Bovine
Serum Albumin), Lactofferin, Glyco Macro Peptides (GMP). All of which, including
the added benifits of casomorphins are all intact in undenatured micellar
casein. A form of undamaged casein protein which the most significant study
citied (Boire) was used. When using a casein based protein product it is
generally beneficial to find one which contains undenatured micellar casein.
Unlike whey the powder will not dissolve as well and will leave slight lumpy
components to the drink but surely it is the quality that is of superior
importance.
HOW MUCH PROTEIN?
There are 4 calories for every 1g of protein.
Most athletes require around 1g of protein per pound of bodyweight. Some
athletes, especially those with a fast metabolism may need higher amounts from
1.5 to 2 grams per pound of body weight. This fact is often disputed among
scientists, companies and athletes, often being cited much lower at 1g per kg of
bodyweight being the maximum requirement. Of course this would depend on a
number of factors including training intensity, frequency, absorption, quality
of protein etc, specific supplementation designed to absorb more protein, drug
use etc.
COMPETITIVE SPORTS
It is generally considered that those athletes competing in extreme sporting
conditions such as bodybuilding competitions, boxing and serious sprinting etc,
may wish to steer clear of liquid protein drinks, meal replacements or weight
gainers two weeks or so prior to a competition. This purely and simply is to do
with the sodium content of many of these products. When trying to appear more
muscular or bring down bodyweight stored body water can cause some problems.
Techniques such as sodium depletion and carb loading are critical to the
competing athlete and the sodium content of these liquid foods may be
unbeneficial at these stages of contest preparation.
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