The Role of Nutrition on Our Health
Food and Nutrition Services
www.mmhok.com
580.286.7623
Power of Protein
Inside:
Protein Basics
1
Amino Acids
2
Protein Structure
3
Protein Turnover
4
Protein Functions
5-6
Food Sources
7
Additional Resources
8
Special points of interest:
• Varying your protein sources
helps ensure proper body
functioning
• Proteins make us unique!
• Concerned about your weight?
You might be eating too much
protein!
Proper nutrition is made up of 6 group of
nutrients. The macronutrients fats, proteins,
and carbohydrates are those we need in
larger amounts as they provide our bodies
with energy. The micronutrients vitamins
and minerals, do not provide any calories
(energy) but they are critical important to
maintain our health. Water or fluid is also
considered an essential nutrient group.
important in a multitude of body functions
like providing energy/fuel, transporting
vitamins, protecting organs, maintaining
body temperature, and building body cells.
Fat is so important that it should make up
20-35% of all the calories that we consume
in a day.
Where our energy comes from...
Almost all the calories our bodies burn in
a day comes from the carbohydrates and fat
we eat. Carbohydrates (also known as
sugar, blood sugar, glucose, and carbs) are
nutrients found in grains, fruits, vegetables,
dairy products, and beans and are
specifically designed to be the perfect fuel
source. Carbs are often misunderstood and
falsely accused of being “fattening” which is
misleading and not entirely correct. In fact,
carbs are so essential to your diet that
45-65% of all your calories should be
carbohydrates!
Fat is often viewed as the enemy and
again, this is an incorrect assumption. Fat is
What are Proteins?
Proteins are large complex molecules composed of chains of amino
acids. There are 20 amino acids that combine in literally tens of
thousands unique combinations to form different proteins. Amino
acids, and thus proteins, can contain 4 atoms– carbon, hydrogen,
oxygen, and nitrogen. These amino acid protein sequences play a role
in just about all of the functions in our bodies. Protein helps build
muscles, tissues, and bones as well as maintains fluid balance, and
producing enzymes and antibodies.
Amino acids are found in animal products like meat and dairy.
Other abundant sources include beans, nuts, and seeds.
Depending on your age and activity
level, well over half of your daily calories
should come from carbohydrates and fat.
This simple fact surprises many people
because it minimizes the need for a very
popular nutrient– protein. So, if protein is
not intended to be a major calorie (energy)
source, what is it for? Read on and find out!
The Role of Nutrition on Our Health
Page 2
Essentially Awesome
Amino acids (AA) are the building blocks of proteins.
Scientists have identified 20 amino acids that are critical
for proper human growth and development, but there
could be even more!
Amino acids are divided into 2 groups: the essential
and non-essential. The human body cannot manufacture
9 of the AA’s so it becomes essential that they are
consumed in the diet. The other 11 can be produced in
the body so they are nonessential components of the diet.
However, for the body to make the nonessential AA’s, a
person must consume adequate amounts of the essential
AA’s as they provide the ingredients.
Simply put, a healthy diet should have varied protein
sources to ensure adequate intake of the essential AA’s.
Show Me the Science!
All 20 AA’s have a very
similar molecular structure,
meaning they are all made
up of the same atoms in
slightly different
arrangements. AA’s are
composed of a carbon atom
in the center of the
molecule, an amine group
containing nitrogen, an
acid group with a double
bond and oxygen, a
hydrogen atom, and lastly,
a unique side chain.
Figure (a) shows a generic amino acid with all components branching off from the
central carbon atom. Figure (b) illustrates the different atom arrangements in the side
chair (green boxes) which results in distinctive AA’s. The components of essential
AA’s consumed in our food can be used to build the nonessential AA’s.
Conditionally Essential Amino Acids
The essential AA’s that must be obtained in the diet can be used to produce the nonessential AAs if needed. In
most people, this process works perfectly well. However, sometimes there is a problem with the way the body handles
AA’s. For example, babies born with phenylketonuria cannot breakdown the essential AA phenylalanine into the
nonessential AA tyrosine. Thus, phenylalanine builds up in the body without being converted and can cause brain
damage. Also, tyrosine has become conditionally essential in that individual and they must obtain it in the diet.
Phenylketonuria is a rare and serious condition. People diagnosed early can have fairly normal lives with proper
growth and development as long as they maintain a diet very low in many common foods containing phenylalanine
(dairy, beef, nuts) and use supplements to partly make up for the nutrition they lack from these foods. All US hospitals
run a simple blood test shortly after a child’s birth to look for the condition.
The Role of Nutrition on Our Health
Page 3
How Do Amino Acids Make Proteins?
Simply stated, proteins are long series of AA’s stuck
together. This forms a protein chain. There are thousands
of AA’s in the body at any time and of those, there are 20
unique structures. So, those can be arranged in a chain in
a nearly endless combination of ways to create different
proteins. This is important because protein chains of
various lengths and orders of AA’s determines what the
protein will ultimately function as in the body.
The components of one AA’s acid group and another
AA’s amine group combine in a peptide bond linking the
two AA’s together. Some atoms are not needed and
those are “kicked out” of the bond to join separately as a
molecule of H2O (water) that our bodies can use to help
maintain fluid balance. The normal healthy processes of
the human body do not let much go to waste!
Can My Blood Sugar Be Too Low?
Protein Structure
A protein’s structure has 4 levels.
Primary: the sequential order of amino acids. In other
words, in what order AA’s bond together.
Secondary: the spiral or folded shape of the protein chain
caused by the AA bonds.
We all have a unique genetic code. Our genes make
tiny changes to the amino acid sequences which leads
to differences in our individual protein chains. This
results in our distinctive physical
characteristics.
Tertiary and Quaternary: further folder, twisting, and
bending of the protein chain. The resulting structure can
be a globular shape (may form a red blood cell) or fibrous
(may become part of a tendon).
The Role of Nutrition on Our Health
Page 4
Protein Turnover
The proteins in your body are eventually used up and
need to be replaced. Amino acids (the building blocks of
proteins) come from two places– the food you eat and by
degrading (recycling) structures in the body that contain
protein chains. Your body has an Amino Acid Pool which
is like temporary storage for AA’s before they are bonded
together to make proteins.
Humans are composed of billions of cells. Each cell
contains a nucleus which houses DNA, the genetic
instructions or blueprint used in the development and
functioning of all known living things. It is the DNA that
decides how the body will function and what biological
materials will be produced. In other words, each cell has
a little brain that is very aware of what our bodies need at
any given time. Pretty amazing, huh?
There are many functions that AA’s and proteins can be
used for in the body including creating hormones, enzymes,
DNA determines how to combine amino acids to build
antibodies, and cell components as well as maintaining fluid specific proteins. Every single cell has the capacity to
balance. Proteins can also function
instruct the body to build the infinite number
of protein combinations. However, that
as an energy source.
approach would be repetitive and wasteful.
The figure below illustrates just a
So, our cells have specialized in certain areas
few things the body can do with
to produce different proteins if and when
AA’s gathered from the AA pool.
they are needed. For example, all cells can
produce the protein-based hormone insulin,
but only the cells in your pancreas actually
do. Another example is when we cut
ourselves. When we bleed, DNA tells the
body to build blood clotting proteins. We do
not produce these proteins continuously
because we do not need them all the time!
The Right Stuff
In order for our bodies to make the
specific proteins required at any given
time, all the proper AA ingredients
must be available. If not, then the
missing AA becomes the limiting AA
and the protein is incomplete. Without
a complete chain, our bodies cannot
function properly and we may get sick
more often, have trouble digesting
food, and our cells may even start to
die.
It is vitally important not to just eat
enough protein foods, but to eat the
right kinds that contain a variety of
amino acids. A “complete” or “high
quality” protein food contains all 9
essential AA’s from which the body
can build the other 11 nonessential
AA’s. These foods are mostly animal
sources like eggs, meat, and milk,
although soy products are also good
sources.
In general, American diets are very high in
protein. However, many people forget to vary
their protein sources! The figure below shows
complementary protein foods.
The Role of Nutrition on Our Health
Page 5
Protein Functions– Cell growth, repair, and maintenance
Perhaps the greatest function of protein is to maintain the health of billions of body cells.
The human body is in a constant state of change just to support daily functioning and protein
is vital to this process. For example, red blood cells have to be replaced every 3 months and
the cells lining the digestive tract are renewed every 3 days! Amino Acids from food and
from recycling old protein chains make these tasks possible.
Enzymes and Hormones
Enzymes are proteins that
are involved in numerous
chemical reactions in the body.
They can break apart molecules
which is an essential part of
digesting food. Enzymes can
also build and rearrange
molecules which is one way we
convert and store energy in our
bodies.
Hormones are chemical
messengers that send signals
throughout the body. Some
hormones are made from
protein chains. These
hormones are manufactured
and stored until we need to use
them to maintain homeostasis
or balance within our bodies.
When we eat carbohydrates,
enzymes (proteins) begin
breaking apart and rearranging
the large molecules into the
simple sugar known as glucose.
Also called blood sugar,
glucose is our primary energy
source and the hormone insulin
helps us to utilize that energy.
Fluid Balance
As protein travels, it attracts fluid and pulls this
fluid out of body tissues which allows it to continue
circulating throughout the body (see figure below).
This is an important process because it is through
fluid that we transport nutrients as well as pick up
waste products for disposal.
Water is a molecule made
of 2 hydrogen atoms and 1
oxygen atom.
Acid:Base Balance
The basic processes of our bodies are always creating acids and bases.
These substances are transmitted through the blood and are expelled
through the lungs as we breathe out or are excreted via urine. Our bodies
maintain a very stable pH balance with the help of proteins. Remember,
proteins are made up of long chains of amino acids. AAs are composed
of carbon, hydrogen, oxygen, and sometimes nitrogen ,and sulfur. If our
blood becomes too acidic or too basic, a protein chain acts as a buffer
and can sacrifice itself by donating components to bring the body back
into pH balance.
If a person does not consume enough protein,
there is no force to attract and pull fluid out of
body tissues. This can be one cause of edema or
swelling of tissue due to increased fluid build up.
Immune System
When invaders or antigens like allergens, viruses, toxins, and
bacteria attack our bodies, we fight back with protein-made
antibodies. Once an antigen is detected, protein gets to work
building more antibodies that attach to the invading substance and
destroy it! Although the process works well, it is very slow. Antibodies take time to produce so you will normally
have a cold for a couple of days before your body has a chance to create the proper army and mount a full attack
against the enemy. However, once a certain antibody has been produced, the process of replicating it at a later date
becomes much quicker! That is why most people only get the chicken pox once. After your body assembled a
specialized antibody force for that particular virus, it quickly recognizes the invader next time and squashes it before
you feel any ill effects! It is important to note that although protein fuels the production of antibodies, eating more
protein when you feel a cold coming on will do nothing but provide you unnecessary calories.
The Role of Nutrition on Our Health
Page 6
Protein as Energy
Protein does provide energy
(calories). For every gram of
protein, there are 4 calories of
energy. Unlike carbohydrates and
fat, protein is not intended to be
used as a primary energy source.
As you have read, protein has
many other important functions
and really cannot be spared to be
used as energy. An unbalanced
diet that lacks carbohydrates and
fats will force the body to begin
pulling proteins out of blood and
liver and muscle tissue which is
not a good thing! However, there
are times when our bodies have
used up our readily available
stored energy.
Nitrogen Balance
To use proteins for energy, the
body breaks the amine group off
of the amino acid.
The nitrogen
becomes a waste
product and is
excreted in the
urine. The body
can then rearrange
the other
components to
form glucose, an
energy source. The remaining
protein components cannot be
recycled back into the AA pool
once broken in this way.
The nitrogen content of urine and feces
can actually be measured to determine
whether a person has a balanced
protein intake versus protein output.
Nitrogen is excreted when proteins
are used for energy and when protein
components are recycled back into
the AA pool. Based on the nitrogen
content of your diet and the nitrogen
excreted from your body, lab tests
can show if you are gaining protein
(building tissues, growing, pregnant,
post-illness), losing nitrogen (poor diet,
illness, starvation), or are in balance. An
adult should ideally be in protein balance.
How Much Protein Should We Eat?
Proper protein intake depends on
your age, activity level, and health
status. An average adult requires 0.8
grams of protein per kilogram (kg)
of their body weight.
Protein
needs
(grams)
100 pounds (45 kg)
36
125 pounds (57 kg)
46
150 pounds (68 kg)
54
175 pounds (80 kg)
64
200 pounds (91 kg)
73
250 pounds (114 kg)
60-70*
300 pounds (136 kg)
60-70*
*assuming obesity status where weight loss is
recommended
An easier way to think of it is that
you need anywhere from 10-35% of
your calories as protein. Most of us
only need about 10% of our calories
to come from protein sources.
People who are building tissues
like children, adolescents, and
pregnant women need closer to the
35% range. Vegetarians need more
protein because amino acids from
plant sources are not processed by
the body as efficiently as those
from meat products.
Athletes need more protein
because their tissues require
increased levels of oxygen.
Hemoglobin, a protein, transports
that oxygen to the cells. Regular
exercise also damages and then
repairs tissues which requires
protein. Do you or your athletic
children need to add protein to your
diet? Probably not. Many
Americans overeat protein by about
50%.
Unless your child is in a
sport where a certain weight
class or body type must be
maintained, they probably
get plenty of protein in
their diet. There is no
need to treat your
son’s basketball team to
steak dinners!
Too Much Protein?
Eating too many calories regardless
of their source (carbohydrates, fats, or
proteins) will ultimately end with
unhealthy weight gain. Excess calories
have to be stored, after all! But,
overconsumption of protein can also
contribute to heart disease and high
cholesterol. Most Americans over
consume protein from meat sources
which are often high in saturated fats
and cholesterol– not a good
combination. Animal products also
contain certain AA’s that disrupt the
natural acid:base balance. To buffer
these acids, calcium, a base, is
pulled out of our bones which
may cause bone loss leading to
osteoporosis.
People who already have or
are prone to kidney disease
should be conscious of
protein foods and limit
intake to the
recommended amount
(see chart at left).
The Role of Nutrition on Our Health
Page 7
Protein Food Sources
Protein is not difficult to find in our foods. Remember, the average woman needs about 50 grams of protein and the
average man needs around 60 grams per day. Use these charts to help you get an idea of how much protein you are
eating. You might be surprised just how quickly it adds up!
Helpful tips: 1 ounce is a cupped palm of food. 3 ounces is the size
of your palm or the size of a deck of cards. 8 ounces is a cup. 1
cup is about the size of an average adult fist.
The Role of Nutrition on Our Health
1301 E Lincoln Rd
Idabel, OK 74745
Phone: 580.286.7623
Page 8
McCurtain Memorial Hospital was
originally established in 1954 and
exists to provide excellence in
healthcare. Our vision is to be the
healthcare provider of choice in our
region.
We are proud to be working for a healthier community. We understand that
actions speak louder than words and that is why we take our mission and
vision seriously. We are always striving to improve our services and we value
your feedback.
Resources:
McCurtain Memorial Hospital:
local phone: 580.286.7623
Toll free: 1800.867.1182
http://www.mmhok.com
Be sure to “like” us on Facebook!
McCurtain Memorial Wellness Center:
Information on the hospital’s on-site gym and
wellness center.
Ken Moore, ATC/LAT, Director of Wellness and
Community Health- 580-208-3179
wcd@mmhok.com
NOTES:
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Abby Bridges, RD/LD, MS