Online Nutrition Book
What is nutrition? The Oxford English Dictionary describes
nutrition as "the process of providing or obtaining
the food necessary for health and growth". Nutrition
could also be described as the complex interrelationships
between the various macronutrients, vitamins and minerals,
and of course, water. Our goal is to find that perfect
balance between fats, proteins, and carbohydrates so
that we may live a long and healthy life, or at least
as long as possible. As scientists continue to better
extrapolate useful information from their research,
we will continue in our search to pinpoint physical
excellence and enhance our level of longevity beyond
our wildest dreams. We certainly have made tremendous
leaps and bounds in better understanding the inner workings
of the human body and the effect food has on it. Let's
just hope we can carry on this level of understanding
into the future, but currently, this is concisely where
modern nutrition stands...
- Fat: What It Is and What
It Does
- The Fat We Eat
- Cholesterol and Its
Effect
- The "Good"
and "Bad" Cholesterols
- What Protein Is
- Protein: What Are
Its Roles?
- Protein Digestion
- How Much Protein
Is Enough?
- What Are Carbohydrates?
- How The Body Handles
Carbohydrates
- How You and Your Body
Should Manage Blood Sugar
- Vitamins and Minerals
- The King of All Nutrients:
Water
Fat: What
It Is and What It Does
What is fat? Does it serve a purpose? If you ask many
on the street , they would assuredly tell you that fat
is "bad" and that they need to get rid of
theirs. While one can certainly possess too much fat,
it does play a vital role in our daily lives and is
misunderstood to say the least. Both dietary fat and
stored fat are necessary for survival, but it needs
to be understood that dietary fat is certainly not causal
of excess stored fat. In chemical terms, fat can best
be defined as any group of natural esters of glycerol
and various fatty acids that are solid at room temperature.
This description best applies for saturated fats, but
unsaturated fats are fats too. However, they are essentially
the same ester groups of glycerol, only they are liquid
at room temperature. Fats play a large role that is
often underplayed by those within the fitness community.
It is not simply something that can be lived without.
Fat serves as insulation for our internal organs. The
heart, kidneys, and other organs are surrounded by adipose
tissue which helps not only to protect them from injury,
but to hold them in place as well. Stored fats also
help to regulate body temperature. Since nearly 50%
of all stored fat is stored right underneath the skin
layer as subcutaneous fat, the body uses it as protection
to temperature change in the environment. That's why
it makes sense to have a reasonable level of bodyfat,
as opposed to having too much or too little. If you
are heavy, you probably tend to overheat rather easily,
while the excessively slender find themselves cold more
often than those with more bodyfat. Lastly, stored body
fat serves an integral part of hormone production and
regulation. While many may find this to be strange since
most hormones, or the body's chemical messengers, are
produced in glands throughout the body. However, some
of our most recognizable and important hormones are
derived from adipose tissue. One example of the hormone
regulating abilities of adipose tissue can be found
in subcutaneous tissue as the lipid, 7-dehydrocholesterol.
When the skin is exposed to sunlight, the 7-dehydrocholesterol
is converted to the fat-soluble vitamin D which is vital
to maintaining bone health. Secondly, fatty tissue also
serves as an integral part in the regulation of estrogen
production. It is well known and documented that body
fat levels directly influence the menstrual cycle. It
is even possible for the menstrual cycle to cease altogether
if body fat levels become too low, while on the other
hand, obese women may find themselves having irregular
periods and fertility problems as well. Furthermore,
one of the adrenal hormones is converted to estrogen
by the enzyme aromatase in the fatty tissue of both
men and women. This helps to explain why heavier, older
women tend to maintain high levels of estrogen. Fat
is also vital for the breakdown of the fat-soluble vitamins
A, K, D, and E. In summation, fat is truly important
for daily functions, which is why are bodies need a
bare minimum of 12% for women and 7% for men. It protects
our organs, regulates body temperature, nourishes our
skin and helps fortify our bones, without which we'd
be most certainly be dead.
The
Fat We Eat:
While the role of fat has been established, its dietary
role is a different matter entirely. As mentioned earlier,
fat does not beget fat, at least not entirely. While
that eating fat won't directly lead to fat storage,
it does need to be considered that the body is more
efficient at converting dietary fat into stored fat
than carbohydrates and protein. To be technical about
it, roughly 25% of the calories in carbs and protein
are burned up in the fat conversion process as opposed
to only 3% of fat's calories being utilized to achieve
the same results. But, in all fairness, eating a fatty
food does not necessarily mean it will be stored as
entirely as such. A principle that does remain true
is that a gram of fat is equal to about 9 calories,
which is more than double the number of calories found
in either carbohydrates or protein (about 4 calories
for both). So, this too gives us a reason to be aware
of our fat intake and while there are differing opinions
on how much fat is to be eaten, most would say that
between 20-30% of your daily caloric intake should come
from fats. Most of these fats should come from unsaturated
fats instead of saturated fats. The saturation of fat
is basically a term that refers to the type and degree
of chemical bonding found within the fat molecule. For
instance, saturated fats, such as animal fats, are composed
of one fatty acid or a combination of fatty acids which
have single bonds around each carbon. On the other hand,
unsaturated fats, which can be broken down into either
monounsaturated or polyunsaturated, have either one
or two double bonds depending on its classification.
Although it is best to avoid saturated fats, there is
one fat of the heart-healthier polyunsaturated kind
that needs to be avoided: trans fats. Trans fats, or
trans fatty acids, is a term used to describe the process
used to alter the chemical structure of a normally softer,
polyunsaturated fat so that it becomes a harder, more
saturated fat. Since polyunsaturated fats are rather
unstable in the sense that they go rancid if exposed
to too much oxygen, food companies prevent this from
happening by sending hydrogen gas through the liquid
oil in order to replace some of those oxygen atoms with
hydrogen atoms. One of the most common examples of a
hydrogenated food product is margarine. If purchasing
margarine, try to find some that is semi-solid and soft
as opposed to solid margarine. The softer kind has less
trans fats than the solid. Now the reasons as to why
we should avoid trans fats are well documented these
days. Everything from type II diabetes to coronary heart
disease to stroke can all be attributed to a certain
degree to America's high trans fat intake due to our
adoration of fast food, cookies, and potato chips. These
same diseases can be attributed to saturated fats as
well, since trans fats, while originally unsaturated,
have been transformed into an equally dangerous relative
of saturated fat, if not even more dangerous. Both like
to elevate the "bad" LDL cholesterol levels,
lower the "good" HDL cholesterol levels, and
elevate triglyceride levels, which simply is the chemical
form fat takes en route to fat cells for storage. At
the opposite end of the fat spectrum lie several, more
beneficial groups of fats. These are the unsaturated
fats, more specifically called monounsaturated and polyunsaturated,
and even more specifically still, omega-3, omega-6,
omega-9. Omega-3(linolenic acid) and omega-6(linoleic
acid) are both polyunsaturated and these are often called
essential fatty acids since our body cannot produce
them on its own. Omega-6 is pretty easy to come by since
it can be found in sunflower oil, safflower oil, corn
oil, as well as grains, beans, and poultry too. The
one that we need more of is omega-3. More omega-3 in
the diet will mean smoother joint function, lowered
risk of coronary heart disease, type II diabetes, as
well as smoother, healthier skin. One has to work a
little harder to ensure omega-3 levels are where they
need to be. Good sources include coldwater fish, such
as mackerel, salmon, and sardines, but can also be found
in leafy green vegetables as well. Lastly, there is
omega-9 which is monounsaturated and is best represented
by olive oil, avocados, and flaxseed oil. Omega-9's
are also known to lower trigycerides as well. Thus,
fat isn't all heart attacks and obesity, as is the case
of unsaturated fats, which are actually flavorful, fat-burning,
and just what the doctor ordered for your heart.
Cholesterol
and Its Effect
Cholesterol. Just the name alone is enough to make
some cringe. All Americans have been conditioned over
the years to be aware of their blood cholesterol levels.
So, what is cholesterol exactly? Is its nasty reputation
warranted? On a technical level, cholesterol is a sterol,
a compound in which the carbon, hydrogen, and oxygen
atoms are arranged in rings. Cholesterol is related
to fats, but they are not necessarily intimately related.
In fact, like fats, there are many reasons to celebrate
cholesterol. Cholesterol is used throughout our body
to create things as different as sex hormones to cell
membranes to nerve sheaths. Also, cholesterol is transformed
into vitamin D via sunlight. However, before you begin
hoarding cholesterol, one must realize that our bodies
naturally produce cholesterol, so, in essence, we could
live just fine without dietary cholesterol. Most cholesterol
is manufactured in the liver and in the lining of the
small intestine, but every cell has the capacity to
make its own to fulfill its own needs if necessary.
In fact, as much as 85% of all cholesterol in the body
is manufactured by our own bodies. If our bodies produce
so much cholesterol naturally then why aren't all Americans
struggling with high cholesterol? Basically, not all
people absorb cholesterol the same. Some can eat very
little and still have high blood cholesterol levels,
while others can eat a tremendous amount and still have
categorically healthy levels. On average, we can absorb
about 50% of the cholesterol in foods, but since every
person is different, this percentage can vary between
20-90% absorption. What makes high blood cholesterol
levels so dangerous is that it leads to atherosclerosis,
or the accumulation of fatty deposits in the coronary
arteries that is the leading cause of heart attacks
in the United States. So, what is a healthy blood cholesterol
goal? Since one's chances for heart attack rise considerably
when in the 200-220 milligrams per deciliter range,
it would be ideal, but a struggle for many, to get down
to 180 milligrams per deciliter. At this point, one's
risk of heart attack is extremely low.
The
"Good" and "Bad" Cholesterols
And while circulating blood cholesterol is important
to know, another accurate indicator of increased cholesterol
levels and cardiovascular risk are the molecules that
actually transport the cholesterol to the cells. In
order for cholesterol to travel through blood, it must
attach itself to small lipid-carrying proteins called
lipoproteins. The higher the proportion of protein in
the lipoprotein, the greater is its density. The least
dense are the chylomicrons, which carry very little
cholesterol. Next, come the very low-density lipoproteins(VLDL),
which roughly carry 15% of the circulating cholesterol.
Following the VLDL are the LDL which are the most notorious
since they carry roughly 65% of all circulating cholesterol.
High LDL levels are almost always a sure sign of atherosclerosis.
Lastly comes the "good" cholesterol, high-density
lipoproteins(HDL), which are the smallest and densest
of the lipid-carriers. These actually carry cholesterol
from the cells to the liver so that they can be processed
as bile acids, excreted in the bile as cholesterol,
or returned to the plasma as a component of VLDL. In
other words, they dispose of the cholesterol. There
are several notable factors that can dramatically influence
blood cholesterol levels. Anything from genetics, weight,
and gender, to age, diet and exercise can all have a
direct effect on one's cholesterol levels. The way one
should go about lowering cholesterol levels is several
fold, and not necessarily in sequential order. First
of all, exercise more. This will help control weight
and elevate HDL levels. Secondly, one should try to
lose weight since the overweight tend to exhibit higher
cholesterol readings than thinner people. Thirdly, when
cooking, try to cut out as much cholesterol and saturated
fat as possible. This also means cutting back on trans
fat consumption too. Next, one should try to eat more
fiber since it has been known to lower cholesterol as
well as switch out fattier milk and cheese for options
with less fat.
What
Protein Is
Why is protein important and why should it be a necessary
component of our diet? First off, protein shares the
same building materials as carbohydrates and fats, that
is, a carbon backbone with hydrogen and oxygen atoms
attached. The difference lies in the fact that proteins
carry nitrogen atoms. All proteins are comprised of
building blocks called amino acids. In totality, there
are 20 different amino acids with 9 being essential
and the other 11 being nonessential. The terms, essential
and nonessential, are used to describe whether or not
an amino acid is manufactured within the body or needs
to be acquired from the diet. Of course, nonessential
pertains to those 11 manufactured within the body. These
amino acids are linked together by structures called
peptide bonds. Thus, these bonded chains of amino acids
are the simple components of all proteins.
Protein:
What Are Its Roles?
Protein has many roles in our body that other macronutrients
simply cannot do on their own. Appropriate amounts of
protein are needed for tissue growth and maintenance.
Protein is needed for the proper development of the
fetus, the production of human milk, the healing of
a wound, and the growth of nails and hair. As for tissue
maintenance, protein is perpetually engaged in replacing
amino acids used in the muscle tissue, blood, skin,
internal organs, and connective tissue. This process
of amino acid degradation and reconstruction is called
protein turnover. Another role of proteins is to help
in the production of enzymes and some hormones as well.
One example is insulin which is the hormone that regulates
blood glucose levels. Even our immune system's antibodies
are composed of proteins. Certain proteins have the
job of transporting nutrients and other substances through
the bloodstream. An excellent example would be hemoglobin,
our body's iron-rich protein in charge of delivering
oxygen from our lungs to all of our body's tissues.
Even lipoproteins depend on proteins to help them transport
lipids in the blood. Lastly, protein can also serve
as a source of energy, but it is not as efficient as
carbohydrates and fats. Plus, this process can leave
behind too much nitrogen which can eventually become
toxic. In conclusion, protein's roles are vast and varied.
Protein
Digestion
Digestion for proteins is an ornate process that truly
begins once we see and smell our food. Just when we
begin to smell something appetizing, our body begins
secreting various enzymes and stomach acid, so that
once we actually ingest the food, our body will be able
to more efficiently denature the proteins and dismantle
the molecules for easier digestion. Next, protein digestion
is continued in the small intestine where the alkaline
pancreatic juices and acidic stomach acids meet so as
to neutralize each other and break down the polypeptides
into amino acids, which are then absorbed into the blood
and taken to the liver. The absorption rate of protein
is very high, with nearly 97% of animal-derived proteins
are absorbed whereas 78-85% of plant -derived proteins
are absorbed. Once absorbed into the liver, the body
has a few options on how the amino acids will be put
to use. One possibility is that the amino acids will
be used by the liver to help manufacture its own proteins
as well as liver enzymes, lipoproteins, and albumin.
Meanwhile, other amino acids enter the bloodstream where
they unite with other recently liberated amino acids
that have since been sloughed off in the synthesis/
breakdown cycle. At this point, these amino acids come
together to synthesize the amino acids necessary for
bodily function. Without both essential and nonessential
amino acids, protein synthesis would not be able to
take place and amino acids are not able to be stored
like excess fat. Instead, they are shipped back to the
liver where they are stripped of their nitrogen and
passed through the urine while the remaining skeleton
is converted into glucose and used for energy, fat storage,
or glycogen storage.
How
Much Protein Is Enough?
How much protein is appropriate? Can one have too much
of it? If so, what are the drawbacks? While the exact
protein requirement is different for everyone due to
various factors, such as age, body size, composition
of diet, activity level, and state of health, the recommended
amount for a healthy adult is 0.8 grams per kilogram
of bodyweight. A kilogram is roughly 2.2 pounds. One
exception to this rule is the recommended levels for
pregnant women. It is preferred that pregnant women
eat 10 grams more each day than the recommended amount.
Lactating women require an additional 15 grams of protein
during the first six months of nursing, and an additional
12 grams after that. While protein is as vital to cellular
metabolism as oxygen, there certainly lies a threshold
for healthy and unhealthy consumption levels especially
for those in poorer health. Processing protein requires
a lot from kidneys and liver which is why those with
problems with either of those organs are often ordered
by their physicians to eat a lower protein diet. An
indirect drawback from excessive animal protein consumption
is its effect on the cardiovascular system. Since many
meats contains a fair amount of saturated fat, this
can lead to artherosclerosis or hardening of the arteries
as well as obesity. For example, only 25% of a T-bone
steak's calories come from protein while the rest comes
from saturated fat. Even a leaner cut of beef like a
flank steak is still roughly 50% fat. The same holds
true for eggs. Only 31% of eggs' calories come from
protein. Fish and chicken are certainly better sources
of protein. Remember when eating a diet higher in protein
to drink plenty of water in order to replenish the considerable
amount lost during protein metabolism. Lastly, one of
the most dangerous scenarios when it comes to high protein
consumption is when the heavy protein intake is coupled
with a low carbohydrate intake. Diets such as these
are called ketogenic diets due to their reliance on
converting fat into ketones for energy use in the virtual
absence of glucose. For the first several days of a
ketogenic diet, muscle tissue and organ tissue is broken
down to keep the metabolic rate up until your body catches
on so to speak. If carbs remain unavailable for glucose,
then the body will attempt to conserve essential protein
by burning fatty acids. Ketones are the result, but
they can only fuel some of the central nervous system's
cells, not all. As more and more fat is burned in this
process, more and more ketones accumulate in the blood
stream finally resulting in ketosis. Ketosis will ultimately
result in coma and then death. Ketogenic diets often
boast of dramatic weight losses in the the initial phases.
However, most of the weight loss is water due to the
kidneys struggling to flush out the accumulating ketones.
While fat can be lost on such diets due to the controlled
starvation, it is no more successful to eat large quantities
of protein and very little carbs as it is to eat a balanced
diet of equal caloric value. Since ketones make the
blood more acidic, symptoms such as headaches, fatigue,
nausea, vomiting, and dizziness are common. Furthermore,
research is now revealing the risks that such diets
present to your cardiovascular system. Protein is an
essential component in everyone's life, but as with
other macronutrients, there are safe levels of consumption
and then there are unsafe levels of consumption. Try
and stay on the safe side by avoiding extreme high-protein
diets full of saturated fats like the ketogenic diets
just previously discussed and you will be in much better
physical standing.
What
Are Carbohydrates?
Carbohydrates is quite possibly the most misunderstood
of the nutrients along with fat. It too has been vilified
as the reason as why Americans are overweight when in
fact that can be blamed on a lack of dietary willpower
and lack of activity. As it is with all things, too
much of a good thing can end up being quite detrimental.
All carbohydrates serve the tremendous purpose of providing
energy to the body's tissues. More specifically, carbohydrates
provide energy for the brain and its central nervous
system as well as the muscle cells in the form of glucose.
Structurally, carbohydrates consist of chains of carbon,
hydrogen, and oxygen which can come in a vast multitude
of configurations to form plant foods such as wheat,
potatoes, and plums. There are only two types of carbohydrates
total: simple carbs and complex carbs. Simple carbohydrates
are sugars whose bonds are easily broken via digestion.
Sugars are found in all fruits, some vegetables and
honey among other things. There are two types of simple
sugars, monosaccharides and disaccharides. Monosaccharides
have only one unit of sugar making them the most basic
of sugar molecules. Examples include glucose, also known
as blood sugar, fructose, better understood as fruit
sugar, and galactose, which occurs in milk. The second
group, the disaccharides, are comprised of two units
of sugar. Examples of disaccharides include maltose,
which is found in germinating grain and is used to help
ferment beer, sucrose, which is more commonly known
as table sugar, and lactose, or milk sugar. The other
group of carbohydrates are the complex carbohydrates.
These are technically polysaccharides composed of hundreds
or thousands of simple sugars. The two main types of
complex carbohydrates are starch and fiber. Starches
are polysaccharides that are best digested after cooking.
Foods like rice, beans, and grains would all be virtually
indigestible due to the outer layer of cellulose that
human digestive tracts are unable to break down. Cooking
softens the cellulose shell which makes starches digestible.
How
The Body Handles Carbohydrates
The way the body uses carbohydrates for energy is a
complex process. Other than supplying the brain and
the central nervous system with energy, the process
of burning carbohydrates for energy helps to spare proteins
so that they can be used appropriately as the building
blocks of cell growth and repair. If the body's stores
of glucose run low then fat and protein will have to
provide alternate sources of energy. However, to burn
fat efficiently, carbs are needed in conjunction. The
burning of fats for energy will result in highly acidic
blood and can become fatal if no carbs are provided.
Once the body does have carbohydrates as an energy source,
then things are at their most efficient, especially
if the body relies upon complex carbs as the primary
source more than simple sugars. The reason why complex
carbs keep us energized for longer is simply because
it takes the body longer to break down the molecular
structure of polysaccharides. True digestion begins
in the mouth with enzymes in the saliva and chewing
beginning the breakdown process. After being broken
down further in the stomach, food ends up in the small
intestine where more digestive enzymes bombard the food
and split it into monosaccharides for easy absorption.
From here, the simple sugar is circulated from the liver
into the bloodstream where it is then officially named
glucose. At this point, once the carbohydrates have
been metabolized into its working form, glucose, there
are several options on how it can be used. The first
possibility would be for the body to burn glucose immediately
by disassembling it into smaller components within the
individual cells and releasing carbon dioxide, water,
and energy. The second option, if the glucose isn't
needed, is for it to be converted by the liver or muscles
into glucose's storage form, called glycogen. If this
glycogen is needed then it can be reconfigured back
to useable glucose since glucose is the only useable
form of energy. Glycogen stored in the muscles can only
provide energy to the muscles, while glycogen stored
in the liver can supply any part of the body. It has
been figured that the bloodstream has the capability
to hold roughly an hour's supply of glucose while the
body can only store enough glycogen for half a day's
needs. Lastly, if the all of the glycogen stores are
full then the body is left with no other choice than
to convert the surplus glucose to fat and store it in
the fatty adipose tissue.
How
You and Your Body Should Manage Blood Sugar
Once blood sugar levels rise after eating, they must
then be stabilized by two hormones: glucagon and insulin.
Glucagon helps to raise blood glucose levels when the
bloodstream is running low while insulin serves as a
means of transportation for excess blood glucose. For
diabetics, there are two possibilities for their condition.
First of all, there could be inadequate levels of insulin
that are released while the second explanation could
be the result of the body's inability to properly utilize
insulin. This is why not only diabetics, but all people
should utilize tools like the glycemic index(GI), the
glycemic load(GL), and caloric density to help understand
and control how food affects the body and whether or
not it should be included in the diet. The glycemic
index is a scale ranging from 1 to 100 that determines
how quickly a food causes a spike in blood sugar levels.
A food ranking lower in the scale(less than 55) will
cause a slower spike while food with a high GI score
will cause a near immediate spike. Intermediate GI foods
fall between 56-69 while high GI foods score above 70.
However, the gylcemic index doesn't encompass enough
information to give an accurate assessment. A better
indicator of how a food will affect you is the glycemic
load. The glycemic load includes the glycemic index
but also takes into account the serving size. The glycemic
load is discovered by dividing the glycemic index score
by 100 and then multiplying it by its carbohydrate content.
Carbohydrate content is found by subtracting grams of
fiber from total grams of carbohydrates per serving.
A food with a GL higher than 20 is high, a GL between
11 and 19 is intermediate, and 10 or less is low. Furthermore,
one needs to be aware of the caloric density of food,
or the number of calories a food has per gram. Proteins
and carbohdrates both provide roughly 4 calories per
gram while fat contains 9 calories per gram and alcohol
contains 7 calories per gram. One can use these to find
how much fat, carb, and protein derived calories are
in each serving. In total, about half of our calories
should come from carbohydrates. Utilize the glycemic
index and load wisely in order to successfully control
your insulin levels so that obesity and type II diabetes
never even have a chance.
Vitamins
and Minerals
What are vitamins and minerals? Vitamins are organic
substances derived from animal or plant sources that
are necessary for healthy function. Technically, vitamins
serve as coenzymes that attach themselves to proteins
called apoenzymes in cells to become holoenzymes or
"enzymes" for short. There are 13 vitamins
required, with most needing to be supplemented through
a good diet. Only vitamin D, biotin, and vitamin B5
can be manufactured within the body. Vitamin D is derived
from 10-30 minutes of sunlight exposure while both biotin
and vitamin B5 can be manufactured by intestinal bacteria.
There are essentially two categories used to describe
vitamins: fat-soluble or water-soluble. There are four
fat-soluble vitamins, meaning that with the help of
fat and bile they can be absorbed. The four fat-soluble
vitamins are vitamins D, A, E, and K. Secondly, there
are the 8 water-soluble B vitamins and vitamin C. Water-soluble
vitamins require water for them to be broken down and
absorbed. Interestingly enough, the body can actually
store some of the water-soluble vitamins for weeks or
even months at a time, so daily supplementation is not
always necessary. One of the downsides of overdosing
with vitamins is the fact the the high concentrations
of vitamins and minerals in the intestine can cause
for there to be interference between certain ones. In
addition, when those protein apoenzymes are fully saturated
with vitamins then the excess imitates drugs. Some megadoses
of vitamins have been known to be extremely toxic. For
example, too much vitamin D, a vitamin many associate
with bone health, can lead to calcium deposits in the
heart, and even the development of fragile bones. So,
be aware of your dosages and consult your physician
before drastically altering them. Also vital for daily
function are minerals. Minerals are inorganic elementary
substances that originate in soil and water that are
prominent in all plant and animal life. In the average
adult, minerals comprise of 4% of total bodyweight with
most of the weight orginating from the bones. Minerals
needed in larger amounts, as in hundreds of milligrams
a day, are called major or macro minerals. Examples
of these include calcium phosphorus, and magnesium.
At the other end are the minerals that are not needed
as much and these are called trace or micro minerals.
Example of these include zinc, iron, iodine, copper,
manganese, fluoride, chromium, selenium, molybdenum,
boron, arsenic, silicon, and nickel. Minerals are needed
for virtually every process in the body from oxygen
transport to regulating the heartbeat and maintaining
a healthy fluid and chemical balance. Also, minerals
often combine with vitamins to create enzyme activity
while others actually serve as components of enzymes
and hormones.
The
King of All Nutrients: Water
What are the various roles of water? Do I really need
to drink as much as the media recommends? Water is more
important to our survival than fat, protein, and carbohydrates
combined. Overall, our bodies are composed of roughly
60% water. Our blood is 90% water, our skin is 71%,
and our brain is 85%. So, obviously we need to maintain
these levels by actively rehydrating, but how much is
enough? Most recommend 2-3 liters of water a day, or
8-10 glasses a day. While not deletarious, we probably
don't need quite that much since a lot of fruits and
vegetables are largely composed of water. So, all the
melon and carrots and salads you eat, or should be eating,
contribute to your task of rehydration. Here's an interesting
fact; a well-hydrated person has the capacity to exercise
33% longer than someone who is not well-hydrated. Furthermore,
by being 2% dehydrated one's athletic performance can
be effected as much as 15 %. What water does in our
bodies is complex and multifaceted. Water is a solvent
for vitamins and minerals which it helps transport throughout
our bodies. Water aids in muscle contractions, it serves
as a shock absorber for our joints, eyeballs, connective
tissue and muscles, it regulates body temperature, and
it helps expel waste. In addition, water helps with
digestion, circulation, and keeps the skin moist as
well. In other words, water is vital throughout the
body and takes an active in virtually all processes.
Unfortunately, dehydration affects you that thoroughly
as well. Dehydration is experienced initially in the
places where water concentrations are highest: the skin,
the blood, the brain, and muscles. The initial symptoms
are weakened cognitive ability, headache, weakened muscles,
and muscle strains. Remember that not all fluids are
created equal too. In particular, coffee and alcohol
are diuretics and actually pull fluid out of the system
instead of adding more to it. Finally, one needs to
understand that one doesn't have to be thirsty before
a glass of water is appropriate. Drink about a glass
every hour or so throughout the day and drink even more
in the few hours before strenuous activity. So, when
in doubt, have a drink.
In Conclusion...
In conclusion, our bodies are machines that will perpetually
be subjected to trial and error. Some diets provide
numerous benefits while others don't and are tossed
to the wayside for the greater benefit of mankind. The
same treatment goes for supplements. Multivitamins are
often recommended while the latest weight loss pills
probably are not and will not stand the test of time.
Something that certainly will stand the test of time
though is sound nutrition based upon ample servings
of different and colorful fruits and vegetables and
lean servings of protein washed down with plenty of
water. Together, these components will interact with
each other to help ensure that you continue to function
as efficiently as possible. That too is the definition
of nutrition, that of sound, intelligent nutrition.
So, understand that like all machines, one simple mistake
will not kill you and that one simple act of brilliance
will not save you. Its a process that requires a balance
of daily activities and a balance of food groups at
each meal. It's a struggle, but a struggle that is truly
rewarding in the end.
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