Recommended Readings:
Endocrine Insanity Part I
Endocrine Insanity Part II
Pre Contest Week - An In Depth Analysis
Dextrose, Maltodextrin, and Sodium an In Depth Analysis
Nutrient Density Explored
Essential Fatty Acids - An In Depth Analysis
Minerals
Nearly 4% of our
body mass is composed of 21 metallic elements known as minerals. These
occur readily in nature, particularly in waters of lakes and oceans, dirt,
root systems of plants, and in the structures of those who consume plants
and liquids. These inorganic nutrients are constituents of hormones,
enzymes, and vitamins. 3 general roles of minerals are regulation,
structure, and function: (1) Regulating cellular metabolism by joining
with hormones and enzymes that regulate cellular activity. (2) Supplying
structure in the formation of teeth and bones. (3) Functioning in the
maintenance of muscular contractions, neural activity, heart rhythm, and
acid base balance. They may exist free in body fluids, or combine with
other chemicals.
The thin line
between anabolism and catabolism can collapse if lacking in an essential
mineral. For example, several energy-releasing reactions during
macronutrient catabolism are activated by minerals. Moreover, the
synthesis of the hormones such as thyroxin and insulin, are dependent on
zinc and iodine, respectively. Additionally, they are necessary for the
manufacturing of nutrients such as glycogen from glucose, proteins from
amino acids, etc. Deficiencies can produce a wide range of side effects
such as osteoporosis, muscle cramps, anemia, and such like.
Minerals are
separated into two classes: macro (also know as major or macronutrient
elements) and micro (also referred to as minor, trace, and micro elements)
minerals. Major minerals are required in amounts of more than 100 mg
daily, while trace minerals are defined as those required in amounts less
than 100 mg daily. There are 7 known major minerals, and 14 trace
minerals. Among minor minerals are iron, fluorine, zinc, copper, selenium,
iodide, and chromium. Major minerals consist of calcium, phosphorous,
potassium, sulfur, chloride, magnesium, and lastly, our topic of
discussion, sodium.
Sodium
Sodium (NA) has the
atomic number (the number of protons in a particular atom. Each proton has
a single positive charge) 11. These eleven protons are equally offset by
11 negatively charged electrons (negative charge of one). To fill its
valance shelf, however, sodium loses an electron. This gives it a charge
of +1, making it an ion (atoms with positive or negative charges), more
specifically, a cation (a positively charged ion). A synonym for Sodium is
therefore, NA+. The most commonly known form of sodium is table salt, or
sodium chloride. NA represents 40% of it.

NA+ is water
soluble (can be dissolved/mixed in water, much of this effect is due to
its charge, which is attracted to the highly polar H20 molecule) and
highly concentrated in the extra cellular fluids (ECF) of the body. Sodium
is loosely bound to macromolecules (large molecules, i.e. proteins); one
of its functions is to pass through cell membranes. It operates this way
in order to enforce nutrient transport mechanisms and signal nerve
impulses.
Sodium is also
deemed an electrolyte. That is, a substance which can dissociate into ions
in water. Solutions of electrolytes therefore conduct an electric current
and can be decomposed in a solution (electrolysis). Electrolytes are both
anions (negatively charged ions) and cations (positively charged ions).
The body uses them throughout fluid compartments. The goal is to
distribute them in such a way that within a given compartment--the blood
plasma for example--electrical neutrality is always maintained with the
anion concentration exactly balanced by the cation concentration. Major
groups of cations include sodium, potassium, calcium, and magnesium. Their
negative counterparts consist of chloride, proteins, and bicarbonate,
along with low concentrations of organic acids, sulfate and phosphate. The
maintenance of pH (level of acidity, the lower the pH, the more acidic),
and electrolyte balance is almost always handled by your kidneys.
Approximately 30% of
bodily sodium is located on the surface of bone crystals. The remainder is
found in the ECF. Lastly, sodium constitutes 93% of the cations in the
body, making it by far the most abundant member of this family.
Digestion
Almost 95% of
consumed sodium is absorbed by the body, with the remaining 5% being
excreted in the feces. Sodium in excess, however, is excreted by the
kidneys. Several fundamental pathways are used for sodium absorption
across the intestinal mucosa (mucosal cells are any membrane or lining,
which contain mucus-secreting glands for lubrication). Among these are:
- The
sodium/glucose co transport system, which transpires throughout the
small intestine.
- An electrogenic
sodium absorption mechanism. This occurs in the colon.
- The
sodium/chloride co transport mechanism, active in both the small
intestine and colon.
- Electrically
silent cotransport on Na+, K+ and 2Cl-.
The mechanisms used
for cellular absorption, so that your body can use sodium to properly
function, will be discussed subsequently, along with several other
fascinating digestive traits.
Sodium/Potassium Pump
Before discussing
the 4 aforementioned pathways, it is imperative to understand a transport
system, which plays a vital role in their functions. That is, the
Sodium-Potassium (K+) Pump.
There are two forms
of transport process, as follows:
- Active transport-
assisted transport through the plasma membrane, requiring metabolic
energy to “power” the exchange of materials.
- Passive
transport- the transport of substances through the plasma membrane,
requiring no energy.
To clarify, systems
have a tendency to go spontaneously from higher energy concentrations, to
lower ones (diffusion). For example, if glucose were to move across the
membrane of a cell, it would naturally travel from the higher area of
concentration (outside the cell) to the lower area of concentration
(inside the cell). This is called passive transport because it naturally
occurs, and requires no energy. However, if glucose were to be moved in
the opposite direction (from lower to higher concentrations), it would be
called active transport because it does not occur naturally, but rather,
requires energy.

With that said, the
NA+ K+ pump is a form of active transport. Here is how it works: ATP pumps
ions uphill against their electrochemical gradients through the membrane
by a special protein enzyme known as sodium potassium ATPase (remember,
ase at the end of a word refers to an enzyme) that serves as a pumping
mechanism. Such processes must occur within living cells for optimal
distribution of cellular chemicals. Sodium ions normally stay in the cell,
due to its low levels of concentration. As such, sodium outside the cell
naturally wants to continue to diffuse into the plasma membrane.
Potassium, however, exists in higher levels of concentration and, thus,
tends to diffuse into the ECF. To counteract this (that is, counteracting
a state of equilibrium which would be reached without such pumping
mechanisms) and achieve proper sodium and potassium concentrations
surrounding the plasma membrane, for the maintenance of muscular and nerve
functions, both cations must move against their normal concentration
gradients. This leads to higher levels of NA+ in the ECF, and higher
levels of K+ in the ICF. From this, muscular contractions and nervous
functions, among other vital systems, are able to function at a maximal
rate.
For further
comprehension, here is a quote from the man himself, President Wilson:
To make a long story short, in
the membrane of both muscle cells and neurons are several complex
structures. There are voltage gated channels which allow sodium into the
cell, and there are voltage gated channels which let potassium out of the
cell. Additionally, there are sodium/potassium pumps, which literally pump
three sodiums (against their electrical and chemical gradients) out of the
cell, while only pumping two potassiums into the cell. Three positives out
and two positives in translates to the inside of the cell being more
negative than the outside of the cell. In addition to this, there are also
channels in the membrane which allow more potassium to escape than sodium
to enter, which means that more positive charge leaves the cell than
enters. Finally, negatively charged proteins are manufactured inside of
the cell. The point is simple: by complex
machinery, both neurons and muscle cells set up what is called a negative
membrane potential, which means that the inside of the cell is more
negative than the outside. Secondly, the cell has driven sodium outside of
the cell, against its chemical and electrical gradient; that is, if you
could make the membrane more permeable to sodium, it would rush into the
cell like a bullet out of a gun!
This is precisely what occurs in an action potential. Without going into
horrid detail, there is a certain threshold for each cell to achieve an
action potential. This means that enough positive charge flowing toward
negative charge has to occur in order for the entire cell to conduct an
electrical impulse. Once this is reached, however, the entire cell will go
through an action potential (actually its more similar to tiny action
potentials propagating themselves across the cell). Finally, once
threshold has been reached, there is no stopping the action potential from
spreading across the entire cell! This is why it is
the all or none principle.
For more, refer to:
Is the All or None Applicable to an Entire Muscle?
Sodium/Glucose transport system
I discussed this
mechanism in an earlier issue of JHR, as follows:
Glucose/Sodium transport
system
Earlier in the article I
discussed the sodium/glucose co transport mechanism. This concept falls
under the heading of secondary active transport. Primary active transport
takes place via a pumping system [uses ATP or some other chemical energy
source directly to transport substances]. You see, each of your cells
contain proteins which break down ATP, into ADP + P + Energy, and use the
products to power the pump. The Sodium/Potassium Atpase, pumps three
sodiums out of the cell, and only two potassiums into it. This makes
sodium’s concentration higher on the outside of the cell. Additionally the
inside of the cell is more negatively charged than the outside. Sodium is
a positively charged ion and is attracted to the negative area. It has
been pumped against its electrochemical gradient (concentration is greater
outside of the cell and more negative). Thus, Na+ (sodium) will now move
back into the cell.
There are proteins within a
cell membrane which act to transport glucose. However, the binding site
for glucose has a low affinity for it, unless sodium is bound to it. Due
to the electrochemical gradient, sodium enters a binding site specific for
it on the protein, and when it does so, the protein changes its shape (allosteric
reaction), so that sodium can now bind and be transported into the cell.
This is called co transport because two substances are transported into
the cell together, and secondary active transport because it takes
advantage of the concentration gradient set up by the primary mechanism.
By taking in the proper amount of sodium, you increase the concentration
gradient outside of the cell, and therefore increase sodium’s ability to
bind to transport proteins. In doing so, you not only increase
glucose absorption, but as pointed out, you also further increase water
uptake across the luminal membrane of the intestine as well.
In summary, glucose and sodium couple
with each other to form a co transport system. This process is mediated
by the Sodium Potassium pumping system, which provides the proper energy
for this to transpire.

For more on this,
study,
Dextrose, Maltodextrin, and Sodium an In Depth Analysis.
Electrogenic sodium absorption mechanism
This is called an
electrogenic sodium absorption mechanism because the sodium cation is the
lone ion moving past cells, and its transport is regulated by several
electrical channels. It enters the colon via NA+ conducting pathways
called sodium channels. These channels cause diffusion (passive transport)
inwardly by the downhill concentration gradient. This reaction is
accompanied by anions and water, causing it to flow down the colon lumen
(tube) down to its blood stream. Lastly, the sodium potassium system,
pumps it across the membrane, on the blood stream side of the cell.
Sodium/Chloride Co Transport
This
theory is still being analyzed. But an electro neutral (sodium is
positive, and chloride is negative, so they offset each other, becoming
electrically neutral) NA+ Cl- system has been suggested. This has been
proposed due to the observation that a vast amount of sodium absorption is
usually in the presence of Chloride and visa versa [16]. Mechanisms
have not yet been established. One proposed system suggests paired ion
exchangers, that is, sodium and hydrogen (H+) exchange with chloride and
bicarbonate (HCO3-) [4,22]. This theory states that NA+ and Cl- are
allowed into the cell, in exchange for H+ and HCO3-. The sodium is then
pumped across the cell membrane by the sodium potassium pump, followed by
chloride, which crosses via diffusion.
To
further narrow things down, J. B. Stokes performed a study on the urinary
bladder of the winter flounders [38]. He demonstrated that there is a
clear interdependency between Na+ and Clon net absorption of Cland Na+, respectively, and that the process did not require K+ (which has
often been proposed).
Electrically silent cotransport of Na+, K+ and 2Cl-.
Evidence for a tightly coupled Na+-K+-2Clco transport (NKCC) has been reported in nearly every animal cell. It was
first proposed by Geck et al. [17], and has been investigated for over 2
decades, yet it is still in its infancy. Only broad outlines of the
structure, function, and regulation of this ion transport mechanism have
been suggested.
The
NKCC co transport is a secondary active transport (powered by a
concentration gradient, or an electrochemical gradient, that was
previously created by primary active transport) process, despite its
requirement for cellular ATP. It is generally accepted that this system
appears to function in cell volume regulation, as it tends to make the
cell swell, thus, counteracting cell shrinking. It is electrically silent
(like the sodium/chloride pump). [25].
Hypertension
A
primary concern to heightened sodium intakes is hypertension. Hypertension
refers to an extremely high blood pressure, which is a significant factor
in cardiovascular disease, and renal failure. There are several
possibilities by which sodium increases hypertension. One is that sodium
retention induces water retention (increased bodily fluid volume), which
releases a digitalis-like substance that increases the contractile
activity of heart and blood vessels. Another is that the sodium itself
penetrates the vascular smooth muscle cell, causing it to contract [24].
Sodium induced hypertension occurs in 1/3 of individuals with high blood
pressure. Another major factor is weight. It is estimated that being
overweight causes to 20-30% of hypertension diseases [27, 35]. The highest
incidence of hypertension is found in northern Japan, where the NACl
intake reached 20-30 grams daily [48].
Animal
studies have testified to the negative results of high sodium intakes. For
example, chimpanzees added 5, 10, and then 15 grams of NACl to their usual
diet [11]. Over 20 months blood pressure was significantly increased.
These inflictions were completely reversed, however, within 6 months of
cessation.
Other
animal studies show elevated sodium levels may also increase chances of
stroke, arterial disease, left ventricular hypertrophy, and renal
(relating to kidney) vascular diseases [28].
A
major factor to be considered is salt sensitivity. According to Dr. Tom
Brody [48], salt-sensitive people (a higher increase in mean arterial
blood pressure, in relation to sodium intake) tend to develop hypertension
with an intake of 3-6 grams of NA per day, whereas healthy individuals may
not with up to 7.2 grams a day. A very large amount (20 grams) leads to
hypertension in both salt-sensitive and insensitive people. People likely
to be salt-sensitive are those with already heightened blood pressure
levels, such as those with a family history of hypertension, the elderly,
and those with kidney impairments, which reduce the ability to readily
excrete salt out of your system (as mentioned earlier, kidneys are
responsible for emptying excess salt out of the body) [24,36]. Also,
studies have been composed concerning a genetic variation in the
angiotensinogen gene, which produces the hormone angiotensinogen. This
hormone has been shown to increase chances of hypertension in response to
sodium
[21]. They constrict small blood vessels, which increases blood
pressure. Those with stable kidneys may consume
higher amounts of salt than those with physical impairments, and excrete
excess sodium, well within 24 hours, resulting in no rise of blood
pressure [4, 36].
Results show that those with normal blood pressure and who are not
salt-sensitive, will not lower blood pressure with reduction of sodium
intake, but as stated above, it can be raised via over-consumption [19].
However, for those who are salt-sensitive, or have heart problems,
lowering sodium has been shown to be a promising medicine [39].
Recommendations will be discussed further on.
NA+
related hormones
There
are 3 primary hormones to discuss in the regulation of sodium. That is,
aldosterone, renin, and vasopressin, also know as, Antidiuretic Hormone (ADH).
Renin/Aldosterone
Thankfully, our highly esteemed Administrator of Hyperplasia Research, Mr.
Joe King, has covered hormones extensively. This portion of my article is
based on his work of art:
Endocrine Insanity Part I.
Here is a quote
from him,
describing the two aforementioned hormones:
Endorphin
is also secreted by the adrenal medulla. Endorphin has an
anti-stress
analgesic effect, meaning it can ease the feeling of pain.
The
adrenal cortex is the source of corticosteroid hormones. The adrenal
cortex can
be broken up into three zones, and each zone secretes a different hormone.
ZONE 1
– The outer zone, zona glomerulosa, secretes
aldosterone. Aldosterone is a
mineralocorticoid and is involved in the regulation of sodium and
potassium, blood pressure, and blood volume.
KIDNEYS
The kidneys are highly complex
organs. For purposes of this article, we will only be covering their
endocrine function. The kidneys secrete three hormones:
renin,
erythropoietin, and calcitriol.
Renin is an enzyme released
by specialized cells of the kidney into the blood. It is released in
response to sodium depletion and/or low blood volume. Renin converts angiotensinogen
(a protein released into the blood by the liver) to angiotensin I.
Angiotensin I is converted to angiotensin II by an enzyme in the veins of
the lungs. Angiotensin II acts on the adrenal cortex to stimulate the
release of aldosterone. Aldosterone acts on the distal tubules of the
kidneys to decrease the loss of sodium ions and, secondarily, fluid. This
has the effect of increasing blood pressure. In addition, angiotensin
causes constriction of small blood vessels, which also increases blood
pressure.

The
term mentioned above, “mineralcorticoids,” regulates the mineral salts
sodium and potassium in the ECF. Aldosterone is the most frequent and
vital one. It represents 95% of the mineralcorticoids produced.
It is
important to understand that, with low amounts of sodium, the hormone
aldosterone acts on the kidneys to conserve sodium for proper bodily
functions. High sodium intake, however, blunts aldosterone release,
allowing excess sodium to be excreted in the urine. This was designed,
so as to maintain a normal electrolyte balance throughout a wide range of
dietary intakes.
Antidiuretic Hormone (ADH)
Mr.
King also covered this hormone:
Antidiuretic Hormone (ADH),
also called vasopressin, is synthesized and secreted in the supraoptic
nucleus. The primary function of ADH is regulation of body water and is
secreted whenever the water levels in the blood are decreased. Decrease of
water in the blood can be caused by osmotic diuresis (brought on by an
increase in blood glucose levels, ketone bodies, or sodium loss). ADH is
also secreted when mechanoreceptors (blood volume receptors) in the heart
and pressure receptors in the vasculature are stimulated after blood loss.
After a hemorrhage, ADH causes vasoconstriction, which leads to an
increase of blood pressure.
The term,
“Antidiuretic” is self-explanatory. Anti means against, and a diuretic is
a substance which causes water loss. So this hormone resists water loss.
Exercise
Loss
of water and minerals, such as sodium in sweat, is an important factor
during exercise, especially in hot weather. Excess depletion can promote
severe dysfunctions in the form of heat exhaustion, heat stroke, and
cramps. Sadly, due to improper replenishment of fluids and electrolytes,
several athletes have died during sports such as football. These factors
will play an important role in future issues of JHR, concerning proper
workout nutrition.
Your
body does, however, have a mechanism to control rapid mineral and water
loss. During intense training sessions, the hormones aldosterone, renin,
and ADH (discussed previously) are released. These hormones conserve
sodium loss, even under extreme conditions such as running a marathon in
humid weather.
During
exercise, the pituitary gland releases ADH. This enhances water re
absorption from the kidney tubules, causing urine to become more
concentrated during heat stress. The adrenal cortex additionally releases
the hormone aldosterone (this process, along with renin, was described
earlier), which likewise increases the renal tubules re absorption of
sodium. Aldosterone also reduces sweat osmolarity. As such, prolonged heat
exposure decreases sodium concentration in sweat, which assists in
additional prevention of electrolyte depletion [5, 10, 15].
Pre-Contest Training
These hormones play a
vital role in the subject of pre-contest preparation. Fortunately, the
President of Hyperplasia Journals, Jacob Wilson, tore up the subject in
one of his recent journal entries. Within, you will learn how to
manipulate sodium for tight skin and low water retention on the day of the
show. Refer to:
Pre Contest Week - An In Depth Analysis.
Thirst
Mechanism
Having an appetite for
water and sodium is caused by a complex mechanism.
Water is the largest
constituent in the body. It can represent 55% of the body weight in a
healthy adult. About 70% of the water in your body is intracellular. The
rest is in the ECF. Maintenance of hydration is of prime importance to
proper functions. Therefore, it makes sense that cellular shrinking
(dehydration) and diminished ECF/ICF water volume are two primary causes
for thirst.
Decreased blood volume appears to be detected by cardiac stretch
receptors, and enhances thirst. In regulation of osmolarity, your
osmoreceptors, which are in the hypothalamus, detect increased osmolarity
and induce the thirst mechanism. Now remember, osmolarity refers to
concentration of particles in a solution. If you were to increase sodium,
your osmolarity would likewise rise, and if you were to decrease water
intake, it would likewise rise, and visa versa. Contrary to this, if
osmolarity is decreased, thirst is inhibited. Additionally, increased
sodium Gastric load, apparently detected by putative sodium receptors in
the abdominal viscera, enhances thirst. Again, countering this, increased
gastric water load, detected by the same receptors, decreases thirst [45,
46, 47]. The importance of this, in relation to post-workout nutrition,
will be discussed in future issues of JHR.
Several hormones also play a role in thirst
desire. It appears that the Renin-Angiotensin System (discussed earlier),
plays a primary role. Particularly Angiotensin II. For example, several
studies have been conducted using rats. ANG II was administered by
intracranial injection [12, 40, 41]. It was observed that the animals
stopped whatever they were doing, went to the source of water, and started
to drink, around 1 min after injection, and consumed significant amounts
of water for 10-15 minutes. From an immensely complicated study on the
thirst mechanism, DR. J. T. FITZSIMONS has this to say [23]:
The stimulating
effect of ANG II on drinking is so powerful and so widespread among the
many mammals and birds that have been tested, and the behavior aroused so
apparently normal, it invites speculation on its physiological
significance and on how its effects on drinking fit in with the overall
fluid and electrolyte economy of the body.
So it is clear that
ANG II has a profound effect on thirst appetite. Other factors besides
angiotensin hormones include many central neurotransmitters or paracrine
agents, including catecholamines, serotonin, amino acids, tachykinins,
opioids, and mineralocorticoids [23].
Sodium appetite has
similar mechanisms. An increase in sodium hunger is the second behavioral
response to hypovolemia (decreased water volume). Many mammals in sodium
deficit seek and ingest salt, driven to do so by increased sodium appetite
[9, 37, 42]. Through 50 years of intense research, it has been shown
definitively that the hormones discussed earlier, such as Renin and ADH,
play a primary role in sodium appetite [9, 23]. For example, sodium
appetite is increased in rats by inducing the syndrome of apparent
mineralocorticoid excess [6, 7]. This mechanism is an essential defense
against sodium deficiency, to maintain electrolyte balance, and maximum
efficiency [13, 23]. Sodium depletion is of primary concern during
hard-core training sessions, where sodium loss is rapidly increased [30].
As an athlete, is its
imperative that you listen to your body, and give it the proper
nourishment. So if you are thirsty right now, drink up!
Sweat loss
As
mentioned previously, sodium is water soluble. This relates to a large
amount of sodium loss through sweat during intense training sessions.
Sweat is produced by specialized sweat glands beneath the skin.
Evaporation of sweat’s water components results in a refrigeration
mechanism, to cool the body down.
Typically, a well-assimilated athlete will loose .5L - 3L of sweat during
each hour of exercise. On average, an athlete looses 1-1.5 liters per
hour. Higher intensity results in increased sweat loss. Humidity, heat,
and other weather-related factors will result in increased sweat secretion
as well. Every liter of sweat contains a whopping .6 g of sodium.
This is a vital factor in optimal post-workout nutrition.
It is
also important to note that increasing heat and sweat loss before and
during training sessions is extremely beneficial to the athlete. For more
on this, refer to:
Mobility Training and the Application of Proper Warm-Up for Bodybuilders.
Diarrhea
Diarrhea is a serious problem that causes a quarter of the 10 million
infant deaths that occur each year.
In
adults, it is often caused by food poising, overeating, junk food, etc.
Moderate cases may result in the loss of 50 mmol of NA, CL, and k per
kilogram of stool. High volume cases may produce 70 mmol losses. The World
Health Organization (WHO) has recommended a proper hydration formula
consisting of 3.5 g of NaCl, 2.5 g of NaHCO3 (or 2.9 g of Na citrate), 1.5
g of KCl, and 20 g of glucose or glucose polymer. The glucose assists in
intestinal absorption of sodium ions, due to the glucose sodium co
transport system discussed earlier. Ample amounts of water should be
ingested as well. This is usually suitable for most cases of diarrhea.
Osteoporosis
Sodium
has been shown to increase kidney calcium excretion. In the USA, over 90%
of ingested sodium is excreted. It was shown that having 2.3 g of sodium a
day excreted approximately 40 mg of calcium [31, 34]. Likewise, increased
calcium causes natriuresis (increased excretion of sodium). Urinary sodium
has been negatively correlated with changes in bone density in the hip of
postmenopausal women. Decreasing sodium intake or doubling calcium intake
was shown to reduce bone loss equivalently, however [8]. Calcium also has
positive effects on hypertension [20, 43]. Recommendations will be
discussed further on.
Deficiencies
The
range of deficiencies is broad for sodium. These include muscle cramps,
mental apathy, reduced appetite, electrolyte imbalances, dehydration,
hyponatremia, decreased utilization of nutrients, impaired nervous
functions, fainting, imbalanced osmolarity, convulsions, hypovolemia,
hypotension, and further deterioration of renal function [43].
Practical Applications
The
RDA for sodium ranges from 1100-3300 for both men and women. The American
Heart Association recommends 2.4 grams of sodium per day.
Concerning hypertension, patients who have congestive heart failure with
edema, as well as salt-sensitive individuals, have responded to a diet
restricted to 1.5 to 2.0 g sodium a day [2, 18]. Calcium has also been
shown to have positive effects on blood pressure [24]. The National
institute of health consensus panel has recommended having 1,200 to 1,500
mg of calcium daily, which should be helpful in promoting blood pressure
regulation and preventing osteoporosis [20, 43]. For more on calcium, read
Seksi’s article,
Supplement Review - Calcium.
Reducing sodium has been considered for decades an effective way to
improve blood pressure, among other diseases. However, recent controversy
is prevalent. As stated above, lowering sodium will not decrease blood
pressure in already stable individuals. However, it can reduce
hypertension in salt-sensitive and disease-inflicted humans. But, these
results have had high scrutiny lately; the effectiveness of restricted
sodium diets is under serious question [14, 26, 32]. Furthermore,
according to Dr. Tom Brody [48], salt-sensitive people (a higher increase
in mean arterial blood pressure, in relation to sodium intake) tend to
develop hypertension with an intake of 3-6 grams of NA per day, whereas
healthy, normal individuals may not with up to 7.2 grams a day. A very
large amount (20 grams) leads to hypertension in both salt-sensitive and
insensitive people. It should also be noted that hypertension is a complex
subject, and several factors must be considered. For example, studies show
increasing magnesium, potassium, calcium, and fiber, among other foods,
can significantly decrease blood pressure [3].
The
normal human body requires 500 mg of NA+ per day. Athletic requirements
vary, however. As stated above, you can lose more than 500 mg in just an
hour of training. You can very easily lose more grams of salt through
exercise than what is recommended to be consumed total daily. In fact,
many athletes (such as long distance runners) during prolonged exercise in
the heat have been shown to lose 13-17 g of salt daily, more than 8 g of
what is typically consumed. Long distance runners, who do not properly
replace sodium, have indeed suffered fatal consequences. Athletes who do
not replace sodium after hard-core training sessions are severely halting
their results. In fact, if a post workout solution does not contain a
sufficiently high sodium content, excess fluid intake will merely increase
urine output, greatly limiting ample rehydration. Results show that
drinking of plan water in half amount lost corrects only half water
deficit as urinary output remains low for 6 hours of hypohydration. When
large quantities are ingested, this induces urination and sweating, which
limits retention of expanded plasma volume. Moreover, urine output triples
when water intake matches water deficit, and increases 12 fold when intake
is twice as large as deficit [33, 44]! Furthermore,
pure water absorbed from the gut rapidly dilutes plasma sodium
concentrations, decreasing osmolarity, and therefore inhibiting the thirst
mechanism. For more on sodium post workout, refer to,
Dextrose, Maltodextrin, and Sodium an In Depth Analysis.
Besides post workout nutrition, and in some cases during workout
nutrition, athletes generally obtain enough sodium in
their regular diets. I would not include exercise sodium supplementation
to your daily NA+ consumption, however, as you are simply replacing what
was lost.
Exercise Nutrition
With
the foundation laid, in subsequent issues of JHR, we will be investigating
sodium and other factors which coincide with sodium, such as renin, sweat,
etc., and applying them to workout nutrition!
Are You Ready for the
Revolution?
Conclusion
Salt
has great spiritual applications [1]:
Colossians 4:6
6 Let your speech be always with grace, seasoned with salt, that ye may
know how ye ought to answer every man.
Paul
is teaching an important lesson in effectual apologetics (Greek term for
giving a defense of the faith). Christians need to season all their
conversation with grace, seeking to comfort, edify, instruct, and build up
others.
Furthermore, we must, “Be ready always to give an answer to every man who
asketh you a reason of the hope that is in you, with meekness and fear (1
Peter 3:15).”
Christ
said to be as wise as serpents and harmless as doves. As ambassadors of
our Lord, we must be prepared to answer and defend the faith to all men,
always in a loving manner.
Keep it Hardcore,
Venom
Executive of
Bioenergetic Research
Venom@abcbodybuilding.com
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