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Protein
In
the last newsletter we were discussing the importance
of a balanced diet. We talked about
the importance of carbohydrates and the dangers of eating
only carbohydrates or going without carbohydrates. If
you missed it let me know and I'll find it and send it
to you. Hopefully soon we will have all past newsletters
on the web page. This month we will discuss the importance
of Proteins and fats.
Protein is a very important nutrient since it is in every
cell in our body and is the primary structure that composes
our muscles. However, it should not be the nutrient we
eat in place of a healthier balanced nutrition plan that
includes good carbohydrates as well.
Protein is a more complex mix of atoms when compared
to carbohydrates. This is because of the addition of nitrogen
to the carbon, hydrogen, and oxygen mixture. (sorry I
will try to stay away from the biochemistry) Basically
what this means is, when you eat one gram of protein your
body receives 4 calories. We use the term calorie to determine
how much energy you just gained. You also receive 4 calories
of energy when you consume a gram of carbohydrates too.
Proteins are made up of amino acids, of which there are
twenty-two. Eight of these amino acids are considered
dietary essentials and two others are considered as semi-essential.
They are considered essential because our bodies cannot
produce them, and therefore they must be acquired through
the food we eat. It is important to note that the reason
we eat protein sources is not to provide the body directly
with protein but rather, it is to supply the body with
the amino acids it requires to make its own proteins.
With sufficient amounts of carbohydrate available to
meet energy demands, the channeling of protein for energy
is spared and this protein-sparing effect helps regulate
protein metabolism. This is one way we can become deficient
in the essential fatty acids.
As in the case of the high protein diets, if the body
has a level of protein above the body's needs, the excess
is burned as fuel. There is a benefit of a higher amino
acid blood concentration, and that is the release of the
hormone glucagon. Glucagon has an effect opposite to that
of insulin: it increases the release of free fatty acids
from adipose tissue. This is why we loose so much weight
with a no carbo diet but as we learned last time no carbs
are not healthy.
Unfortunately, the burning of proteins is not as clean
as the burning of carbohydrates. This is due to the nitrogenous
waste accumulation mainly in the form of urea. This waste
has to be handled by the body and puts extra stress on
the liver, kidneys, and urinary tract. So lets say you
are on a low carb and hight protein diet. Your liver,
kidneys and urinary tract will most likely have problems
adventually.
Many people ask, "How much protein should or can
I eat?" Current research suggests between 0.8 g/kg
for the average sedentary individual, up to 1.7 g/kg for
a strength resistance exercise. On average, this equates
to 12-15 % of your daily caloric intake.
Fats
Lipids are most commonly known
as fats, oils, waxes, and related compounds that are not
soluble in water. Fats are primarily a mix of carbon,
hydrogen, and oxygen atoms. They differ from carbohydrates
because they have fewer oxygen atoms present. One gram
of fat will give us 9 calories of energy as apposed to
4 from the protein and carbohydrate.
All fats have both saturated and unsaturated fatty acids.
The degree of saturation of fat depends on how many hydrogen
atoms are present, and whether it is liquid or solid at
room temperature. In general, the saturated fatty acids
are worse for the body because they clogg our arteries.
These fats usually come from animal sources and are solid
at room temperature. When a pair
of hydrogen atoms are missing from the fatty acid it is
usually monounsaturated, if more are missing it is polyunsaturated.
Just as there are essential amino acids, there are essential
fatty acids. These are the polyunsaturated fats or Omega
3 and Omega 6 fatty acids. These are the "Good Fats"
that are necessary for body metabolism, and cannot be
manufactured by the body, so they must be supplied in
the diet. These essental fatty acids can be found in foods
like sesame seeds, olive oil, wheat germ, sardines, and
salmon to name a few.
There is another "Bad Fat" structure related
to the unsaturated fatty acids (called the trans fatty
acids or TFA's) that has been getting a lot of publicity
lately. A recent study of 80,000 nurses showed that the
risk of developing heart disease almost doubled for every
2% increase in consumption of TFA's. Trans fatty acids
are fats produced heating liquid vegetable oils in the
presence of hydrogen. This process is known as hydrogenation.
The more hydrogenated an oil is, the harder it will be
at room temperature. It can be found in products such
as margarine, cookies, doughnuts, french fries, fish sticks,
and even baby cookies. They are finding this to be such
a problem the FDA is going to make them put the amount
of trans-fatty-acids (TFA's) on the lables of all foods.
If you want to stay healthy watch out for these TFA's.
After a high-fat feeding that may occur when on a high-protein
diet, there is an inadequate amount of carbohydrate available
for energy needs, and the excess fat is oxidized or metabolized
forming ketones. If these ketones are allowed to accumulate,
the condition known as ketoacidosis occurs, putting stress
once again on the kidneys which try to rid the body of
the intermediate waste products of protein and fat metabolism.
While fat is a necessary nutrient, too much can lead
to obesity, heart disease, and cancer. Limit the fat in
the diet to 30% whereby 10% or less is from a saturated
source. On an average 2000 calorie diet this is 45 grams
of "good fats" and 20 grams of allowable saturated
fats. The lower you keep those saturated fats the better
off you are going to be.
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