By Will Brink
Author of:
Muscle Building Nutrition.com
Muscle Gaining Diet, Training routines by Charles Poliquin
& Bodybuilding Supplement Review
Diet Supplements Revealed
Real World Fat Loss Diet & Weight Loss Supplement Review
Regular
readers of my work have come to expect articles about the
power of whey proteins to potentaily fight cancer and improve
immunity among its many benefits. The ability of whey to
fight cancer, improve glutathione levels and immunity, is
well documented (readers interested in brushing up on the
effects of whey on cancer, immunity, etc, can read previous
articles by me at the LEF’s web site: www.lef.org and
www.BrinkZone.com).
Additional
research suggests possible medical uses for whey that are
quite unexpected and different from whey’s traditional
role as an immune booster and anti cancer functional food.
For example, whey may be able to reduce stress and lower
cortisol and increase brain serotonin levels, improve liver
function in those suffering from certain forms of hepatitis,
reduce blood pressure, as well as other amazing recent discoveries,
such as whey’s possible effects on weight loss, which
is the focus of this article.
What
is whey?
When
we talk about whey we are actually referring to a complex
milk-based ingredient made up of protein, lactose, fat and
minerals. Protein is the best-known component of whey and
is made up of many smaller protein subfractions such as:
Beta-lactoglobulin, alpha-lactalbumin, immunoglobulins (IgGs),
glycomacropeptides, bovine serum albumin (BSA) and minor
peptides such as lactoperoxidases, lysozyme and lactoferrin.
Each
of the subfractions found in whey has its own unique biological
properties. Modern filtering technology has improved dramatically
in the past decade, allowing companies to separate some
of the highly bioactive peptides —such as lactoferrin
and lactoperoxidase—from whey.
Some
of these subfractions are only found in very minute amounts
in cow’s milk, normally at less than one percent (e.g.,
lactoferrin, lactoperoxidase, etc.)
The
medicinal properties of whey have been known for centuries.
For example, an expression from Florence, Italy. Circa 1650,
was "Chi vuol viver sano e lesto beve scotta e cena
presto" which translates into English as "If you
want to live a healthy and active life, drink whey and dine
early."
Another
expression from Italy regarding the benefits of whey (circa
1777) was "Allevato con la scotta il dottore e in bancarotta."
Which translates into English "If everyone were raised
on whey, doctors would be bankrupt.”
Is
whey a weight loss functional food?
A
few years ago, I might have said no. Now I am not so sure.
Although there was a smattering of studies suggesting whey
had certain properties that might assist with weight loss,
a number of recent studies appear to further support the
use of whey as a possible weight loss supplement. Most interesting
– at least to nerds like me - the effect appears to
be not by a single mechanism, but several. This article
will briefly explore a few possible pathways by which whey
may assist the dieter.
“I’m
hungry!”
Human
hunger and appetite are regulated by a phenomenally complicated
set of overlapping feedback networks, involving a long list
of hormones, psychological factors as well as physiological
factors, all of which are still being elucidated. It’s
a very intensive area of research right now, with various
pharmaceutical companies looking for that “magic bullet”
weight loss breakthrough they can bring to market.
One
hormone getting attention by researchers looking for possible
solutions to obesity is cholecystokinin (CCK). Several decades
ago, researchers found CCK largely responsible for the feeling
of fullness or satiety experienced after a meal and partially
controls appetite, at least in the short term.
Cholecystokinin
(CCK) is a small peptide with multiple functions in both
the central nervous system and the periphery (via CCK-B
and CCK-A receptors respectively). Along with other hormones,
such as pancreatic glucagon, bombesin, glucagon-like peptide-1,
amide (GLP-1), oxyntomodulin, peptide YY (PYY) and pancreatic
polypeptide (PP)., CCK is released by ingested food from
the gastrointestinal tract and mediates satiety after meals.
Such
a list would not be complete without at least making mention
of what many researchers consider the “master hormones”
in this milieu, which is insulin and leptin. If that’s
not confusing enough, release of these hormones depends
on the concentration and composition of the nutrients ingested.
That
is, the type of nutrients (i.e., fat, protein, and carbohydrates)
eaten, the amount of each eaten, and composition of the
meal, all effect which hormones are released and in what
amounts…Needless to say, it’s a topic that gets
real complicated real fast and the exact roles of all the
variables is far from fully understood at this time, though
huge strides have been made recently.
Whey’s
effects on food intake.
This
(finally!) brings us to whey protein. Whey may have some
unique effects on food intake via its effects on CCK and
other pathways. Many studies have shown that protein is
the most satiating macro-nutrient. However, it also appears
all proteins may not be created equal in this respect.
For
example, two studies using human volunteers compared whey
vs. casein (another milk based protein) on appetite, CCK,
and other hormones (Hall WL, Millward DJ, Long SJ, Morgan
LM.Casein and whey exert different effects on plasma amino
acid profiles, gastrointestinal hormone secretion and appetite.
Br J Nutr. 2003 Feb;89(2):239-48).
The
first study found that energy intake from a buffet meal
ad libitum was significantly less 90 minutes after a liquid
meal containing whey, compared with an equivalent amount
of casein given 90 minutes before the volunteers were allowed
to eat all they wanted (ad libitum) at the buffet. In the
second study, the same whey preload led to a plasma CCK
increase of 60 % ( in addition to large increases in glucagon-like
peptide [GLP]-1 and glucose-dependent insulinotropic polypeptide)
following the whey preload compared with the casein.
Translated,
taking whey before people were allowed to eat all they wanted
(ad libitum) at a buffet showed a decrease in the amount
of calories they ate as well as substantial increases in
CCK compared to casein. Subjectively, it was found there
was greater satiety followed the whey meal also.
The
researchers concluded “These results implicate post-absorptive
increases in plasma amino acids together with both CCK and
GLP-1 as potential mediators of the increased satiety response
to whey and emphasize the importance of considering the
impact of protein type on the appetite response to a mixed
meal.” Several animal studies also find whey appears
to have a pronounced effect on CCK and or satiety over other
protein sources.
It
should be noted however that not all studies have found
the effect of whey vs. other protein sources on food intake
(Bowen J, Noakes M, Clifton P, Jenkins A, Batterham M.Acute
effect of dietary proteins on appetite, energy intake and
glycemic response in overweight men. Asia Pac J Clin Nutr.
2004;13(Suppl):S64.).
It
should also be noted that although studies find protein
to be the most satiating of the macro-nutrients, certain
protein sources (e.g. egg whites) may actually increase
appetite (Anderson GH, Tecimer SN, Shah D, Zafar TA. Protein
source, quantity, and time of consumption determine the
effect of proteins on short-term food intake in young men.
J Nutr. 2004 Nov;134(11):3011-5.), so protein sources appear
worth considering when looking to maximize weight loss and
suppress appetite.
How
whey achieves this effect is not fully understood, but research
suggests it’s due to whey’s high glycomacropeptide
and alpha-lactalbumin content, as well as its high solubility
compared to other proteins, and perhaps it’s high percentage
of branch chain amino acids (BCAA’s).
Whey’s
effects on bodyfat, insulin sensitivity, and fat burning….
So
we have some studies suggesting whey may have some unique
effects on hormones involved in satiety and or may reduce
energy (calorie) intake of subsequent meals, but do we have
studies showing direct effects of whey vs. other proteins
on weight loss? In animals at least, whey has looked like
a promising supplement for weight loss.
Although
higher protein diets have been found to improve insulin
sensitivity, and may be superior for weight loss (with some
debate!) then higher carbohydrate lower protein diets, it’s
unclear if all proteins have the same effects.
One
study compared whey to beef (Damien P. Belobrajdic,, Graeme
H. McIntosh, and Julie A. Owens. A High-Whey-Protein Diet
Reduces Body Weight Gain and Alters Insulin Sensitivity
Relative to Red Meat in Wistar Rats. J. Nutr. 134:1454-1458,
June 2004) and found whey reduced body weight and tissue
lipid levels and increased insulin sensitivity compared
to red meat.
Rats
were fed a high-fat diet for nine weeks, then switched to
a diet containing either whey or beef for an additional
six weeks. As has generally been found in other studies,
the move to a high dietary protein reduced energy intake
(due to the known satiating effects of protein compared
to carbs or fat), as well as reductions in visceral and
subcutaneous bodyfat.
However,
the rats getting the whey, there was a 40% reduction in
plasma insulin concentrations and increased insulin sensitivity
compared to the red meat. Not surprisingly, the researchers
concluded “These findings support the conclusions that
a high-protein diet reduces energy intake and adiposity
and that whey protein is more effective than red meat in
reducing body weight gain and increasing insulin sensitivity.”
Other
studies suggest taking whey before a workout is superior
for preserving/gaining lean body mass (LBM) and maintaining
fat burning (beta oxidation) during exercise over other
foods taken prior to a workout. The study called “A
preexercise lactalbumin-enriched whey protein meal preserves
lipid oxidation and decreases adiposity in rats” (Am
J Physiol Endocrinol Metab 283: E565–E572, 2002.) came
to some very interesting conclusions.
One
thing we have known a long time is the composition of the
pre-exercise meal will affect substrate utilization during
exercise and thus might affect long-term changes in body
weight and composition. That is, depending on what you eat
before you workout can dictate what you use for energy (i.e.
carbs, fats, and or proteins) which alters what you burn
(oxidize) for energy.
The
researchers took groups of rats and made the poor buggers
exercise two hours daily for over five weeks (talk about
over training!), either in the fasted state or one hour
after they ingested a meal enriched with a simple sugar
(glucose), whole milk protein or whey protein.
The
results were quite telling. Compared with fasting (no food),
the glucose meal increased glucose oxidation and decreased
lipid oxidation during and after exercise. Translated, they
burned sugar over body fat for their energy source. In contrast,
the whole milk protein and whey meals preserved lipid oxidation
and increased protein oxidation. Translated, fat burning
was maintained and they also used protein as a fuel source.
Not
surprisingly, the whey meal increased protein oxidation
more than the whole milk protein meal, most likely due to
the fact that whey is considered a “fast” protein
that is absorbed rapidly due to it’s high solubility.
As
one would expect, by the end of the five weeks, body weight
was greater in the glucose, whole milk protein and whey
fed rats than in the fasted ones. No shock there. Here is
where it gets interesting: In the group getting the glucose
or the whole milk protein, the increase in weight was from
bodyfat, but in the whey fed group, the increase in weight
was from an increase in muscle mass and a decrease in bodyfat!
Only
the rats getting the whey before their workout increased
muscle mass and decreased their bodyfat. The researchers
theorized this was due to whey’s ability to rapidly
deliver amino acids during exercise. Is this the next big
find in sports nutrition or those simply looking to preserve
muscle mass loss due to aging?
Hard
to say at this time being it was done in rats, but if it
turns out to be true in humans (and there is no reason people
can’t try it now) it would indeed be a breakthrough
in the quest to add muscle and lose fat.
Don't
forget to check out Will's two superb ebooks:
Diet
Supplements Revealed
Learn which diet and weight loss supplements burn fat fast
and which are no more than hype... And discover a scientifically
proven, totally personalized fat loss diet all within the
next 10 minutes.
Muscle
Building Nutrition Guide and Bodybuilding Supplements Review
Build serious lean muscle in record time with a proven muscle
building nutrition plan and discover exactly which bodybuilding
supplements work and which are no more than pure marketing
BS.
Effects
on serotonin, blood sugar regulation, and more!
Although
the above would probably be the major mechanisms by which
whey could help the dieter, there are several secondary
effects of whey that may assist in weight loss. For example,
whey’s effects on serotonin levels. Serotonin is probably
the most studied neurotransmitter since it has been found
to be involved in a wide range of psychological and biological
functions. Serotonin ( also called 5-hydroxytryptamine or
5-HT) is involved with mood, anxiety, and appetite.
Elevated
levels of serotonin can cause relaxation and reduced anxiety.
Low serotonin levels are associated with low mood, increased
anxiety (hence the current popularity of the SSRI drugs
such as Prozac and others), and poor appetite control. This
is an extremely abbreviated description of all the functions
serotonin performs in the human body – many of which
have yet to be fully elucidated – but a full explanation
is beyond the scope of this article.
Needless
to say, Increased brain serotonin levels are associated
with an improved ability of people to cope with stress,
whereas a decline in serotonin activity is associated with
depression and anxiety. Elevated levels of serotonin in
the body often result in the relief of depression, as well
as substantial reduction in pain sensitivity, anxiety and
stress. It has also been theorized that a diet-induced increase
in tryptophan will increase brain serotonin levels, while
a diet designed for weight loss (e.g., a diet that reduces
calories) may lead to a reduction of brain serotonin levels
due to reduced substrate for production and a reduction
in carbohydrates.
Many
people on a reduced calorie intake in an attempt to lose
weight find they are often ill tempered and more anxious.
Reductions in serotonin may be partially to blame here.
One recent study (The bovine protein alpha-lactalbumin increases
the plasma ratio of tryptophan to the other large neutral
amino acids, and in vulnerable subjects raises brain serotonin
activity, reduces cortisol concentration, and improves mood
under stress. Am J Clin Nutr 2000 Jun;71(6):1536-1544) examined
whether alpha-lactalbumin – a major sub fraction found
in whey which has an especially high tryptophan content
– would increase plasma Tryptophan levels as well reduce
depression and cortisol concentrations in subjects under
acute stress considered to be vulnerable to stress.
The
researchers examined twenty-nine “highly stress-vulnerable
subjects” and 29 “relatively stress-invulnerable”
subjects using a double blind, placebo-controlled study
design. The study participants were exposed to experimental
stress after eating a diet enriched with either alpha-lactalbumin
(found in whey) or sodium-caseinate, another milk based
protein. They researchers looked at:
Diet-induced
changes in the plasma Tryptophan and its ratio to other
large neutral amino acids.
Prolactin levels.
Changes in mood and pulse rate.
Cortisol levels (which were assessed before and after the
stressor).
Amazingly, the ratio of plasma Tryptophan to the other amino
acids tested was 48% higher after the alpha-lactalbumin
diet than after the casein diet! This was accompanied by
a decrease in cortisol levels and higher prolactin concentration.
Perhaps most important and relevant to the average person
reading this article, they found “reduced depressive
feelings” when test subjects were put under stress.
They
concluded that the “Consumption of a dietary protein
enriched in tryptophan increased the plasma Trp-LNAA ratio
and, in stress-vulnerable subjects, improved coping ability,
probably through alterations in brain serotonin.” This
effect was not seen in the sodium-caseinate group. If other
studies can confirm these findings, whey may turn out to
be yet another safe and effective supplement in the battle
against depression and stress, as well as reduced serotonin
levels due to dieting.
Although
there is a long list of hormones involved in appetite regulation,
some of which have been mentioned above, serotonin appears
to be a key player in the game. In general, experiments
find increased serotonin availability or activity = reduced
food consumption and decreased serotonin = increase food
consumption. If whey can selectively increase serotonin
levels above that of other proteins, it could be very helpful
to the dieter.
Other
possible advantages whey may confer to the dieter is improved
blood sugar regulation (Frid AH, Nilsson M, Holst JJ, Bjorck
IM. Effect of whey on blood glucose and insulin responses
to composite breakfast and lunch meals in type 2 diabetic
subjects. Am J Clin Nutr. 2005 Jul;82(1):69-75.) which is
yet another key area in controlling appetite and metabolism.
Finally,
calcium from dairy products has been found to be associated
with a reduction in bodyweight and fat mass. Calcium is
thought to influence energy metabolism as intracellular
calcium regulates fat cell (adipocyte) lipid metabolism
as well as triglyceride storage. It’s been demonstrated
in several studies the superiority of dairy versus non-dairy
sources of calcium for improving body composition, and the
whey fraction of dairy maybe the key.
The
mechanism responsible for increased fat loss found with
dairy-based calcium versus nondairy calcium has not is not
fully understood but researchers looking at the issue theorized
“…dairy sources of calcium markedly attenuate
weight and fat gain and accelerate fat loss to a greater
degree than do supplemental sources of calcium. This augmented
effect of dairy products relative to supplemental calcium
is likely due to additional bioactive compounds, including
the angiotensin-converting enzyme inhibitors and the rich
concentration of branched-chain amino acids in whey, which
act synergistically with calcium to attenuate adiposity.”
It
appears components in whey – some of which have been
mentioned above - are thought to act synergistically with
calcium to improve body composition (Zemel MB. Role of calcium
and dairy products in energy partitioning and weight management.
Am J Clin Nutr. 2004 May;79(5):907S-912S.).
Conclusion
Taken
in isolation, none of these studies are so compelling that
people should run out and use whey as some form of weight
loss nirvana. However, taken as a total picture, the bulk
of the research seems to conclude that whey may in fact
have some unique effects for weight loss and should be of
great use to the dieter. More studies are clearly needed
however.
So
what is the practical application of all this information
and how does the dieter put it to good use? Being the appetite
suppressing effects of whey appear to last approximately
2-3 hours, it would seem best to stagger the intake throughout
the day. For example, breakfast might be 1-2 scoops of whey
and a bowl of oatmeal, and perhaps a few scoops of whey
taken between lunch and dinner.
If
whey does what the data suggests it does in the above, that
should be the most effective method for maximizing the effects
of whey on food (calorie) intake on subsequent meals as
well as the other metabolic effects covered. If working
out, the schedule may be different however and people should
follow the pre and post nutrition recommendations made in
my ebook Muscle Building Nutrition* or advice easily found
on the ‘net via the many sports nutrition and bodybuilding
related web sites.
*
Ebook can be found at: www.musclebuildingnutrition.com
Additional
references of interest:
Curzon
G.Serotonin and appetite.Ann N Y Acad Sci. 1990;600:521-30;
discussion 530-1.
Pierson
ME, Comstock JM, Simmons RD, Kaiser F, Julien R, Zongrone
J, Rosamond JD. Synthesis and biological evaluation of potent,
selective, hexapeptide CCK-A agonist anorectic agents. J
Med Chem 1997 Dec 19;40(26):4302-7
Blundell
JE, King NA. Overconsumption as a cause of weight gain:
behavioural-physiological interactions in the control of
food intake (appetite). Ciba Found Symp 1996;201:138-54;
discussion 154-8, 188-93
Zittel
TT, von Elm B, Teichmann RK, Rabould HE, Becker HD. Cholecystokinin
is partly responsible for reduced food intake and body weight
loss after total gastrectomy in rats. Am J Surg 1995 Feb;169(2):265-70
Smith
GP, Gibbs J. Are gut peptides a new class of anorectic agents?
Am J Clin Nutr 1992 Jan;55(1 Suppl):283S-285S
Strader
AD, Woods SC. Gastrointestinal hormones and food intake.
Gastroenterology. 2005 Jan;128(1):175-91.
About
the Author:
Will
Brink is a well known medical, fitness, and health writer
for a variety of publications. He graduated from Harvard
University with a degree in the natural sciences, and is
a regular guest on national radio shows and a speaker at
various conventions around the US. His articles on such
topics as cancer, AIDS, weight loss, fitness, and health
can be found in the Life Extension Magazine as well as other
related publications.
He
is also a consultant to major supplement companies, and
regularly co authors articles with different researchers
from around the world. He is most noted for his articles
and work with whey proteins and essential fatty acids in
athletics and the treatment and prevention of various diseases.
He can be contacted at www.BrinkZone.com or PO Box 812430
Wellesley MA 02482
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