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"Get The Skinny."
by Caroline J. Cederquist, M.D.
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Know Your Macronutrients Part 2: Protein
The media blitz about the American obesity crisis is putting
new attention on the nation's dietary problems, but it isn't necessarily
providing the re- education we need to help us overcome them.
Research shows that the majority of us have only a sketchy
grasp of how nutrition relates to how our bodies function, or fail to, and
we often regard nutrition as a minor factor in our overall health.
Of course, nothing could be further from the truth, but even
the most detailed knowledge isn't enough to correct or even prevent
obesity or bad eating habits, thousands of overweight doctors can attest
to that.
Even so, when it comes to your health, ignorance never
leads to bliss, and the more you know, the better equipped you are to
adjust your own eating habits for better health outcomes.
Here, then, is the first of three pieces offering a simple
look at the macronutrients, protein, fats and carbohydrate, the
fundamental nutritional building blocks. You may be surprised by what you
don't know.
Protein First
Of all the nutrients your body needs, protein is the most
vital.
Why? Because it is absolutely necessary to build and
maintain all your body's structures, not only muscles, tendons and
ligaments, but also your circulatory system, brain, organs, immune system,
skin, just about everything.
As old cells slough off these various structures, replacement
protein is constantly needed to build and repair them. If fresh protein is
not available more or less continuously, the structures start to break
down.
Myths About Protein
Many people have false ideas about what protein can do. They expect
protein to give them big muscles, stamina and athletic prowess. They think
that if a little protein is good, a lot must surely be better.
But eating a hearty serving of red meat every night will not
make you robust. The average 150-pound man cannot use all the protein in
an 8-ounce dinner steak to meet his daily requirement, even if he eats no
other protein foods all day long.
That's because the body can utilize only four to eight ounces
of protein at a time. The rest will be converted into carbohydrate for
immediate energy or
stored as fat, because, unlike fat and carbohydrate, protein can't be held
in reserve in the body. You cannot load up on protein Monday and store it
for
use on Tuesday and Wednesday. In fact, the protein you eat at breakfast is
pretty well used up by dinner time.
Protein in weight-loss
It would be nice if your body burned only the excess fat you
are anxious to shed. Unfortunately, it doesn't work that way.
Even to function at a minimal level, our bodies first use
available carbohydrate, then protein, and last turn to our fat stores for
energy. The very process of burning body fat requires the presence of
carbohydrates. If there are insufficient carbs and protein in the food you
eat, your body breaks down lean body tissue for the proteins, and converts
them to carbohydrate for energy.
That's why people on some low-calorie diets lose muscle mass
when they're trying to lose fat. If there is a deficiency of dietary
protein, the body
essentially cannibalizes its lean mass for the energy to burn its fat
mass.
And if the body does have to turn to its own tissues for an
energy source, it perceives this as a threat to survival, which it could
be, and it slows the
metabolism, so that the body uses less and less energy to function
overall.
But that's counterproductive in any weight-loss effort, and
shows why starvation diets don't work. You want your body to use more of
what you take in, not less. So ensuring adequate intake of small amounts
of protein spread through the day keeps our bodies from turning to lean
tissues for energy, and helps keep metabolism optimal. That's what's meant
by the expression "feed your diet."
Complete and Incomplete Proteins
Proteins are made from chains of amino acids, of which 20
have been identified so far. Nine are called "essential" amino
acids. They are essential in
your diet because the body cannot manufacture them. The other 11 can be
made in the body from remnants of leftover carbohydrates, fats and
other
amino acids.
Foods that contain all nine essential amino acids are
considered complete proteins. Those containing less than nine are called
incomplete proteins. Most animal proteins fall into the category of
complete proteins: meat, poultry, fish, eggs, milk, cheese and other dairy
products. Except for soy, proteins from plant sources are
incomplete.
However, as any vegetarian can tell you, you do not have to
eat animal proteins to have an adequate diet. All you have to do is
combine foods that supply all nine essential amino acids.
For example, rice is very low in lysine but high in
methionine, both of which are essential amino acids. Beans are low in methionine, but high in lysine.
Served together, they provide a complete protein meal without the expense of prime cuts of meat.
There's solid nutritional science behind cheap cuisines based on rice and beans.
Similar logic holds for the pairing of legumes and grains, the ingredients of a peanut butter sandwich.
It's also true for dairy and grain combinations, as in macaroni and cheese. These are called
complementary proteins.
The catch is that these combinations must be eaten together or within a few hours of each other, or the
benefit of pairing them for the complete protein is
lost. But when you consider all the options, you can see how easy it can be to give your body the little
protein infusions it needs throughout the day to be
functioning at its best.
THROUGH THICK AND THIN
The challenge when choosing your protein sources is to avoid foods that are also high in fat and
cholesterol. For example, the fat in a hamburger may
almost equal the protein. And peanut butter has almost twice as much fat as protein, bringing the
calorie total for two tablespoons to a whopping 190
calories! On the other hand, a serving of fish has very little fat, in most cases, less than one-fifth of
an ounce, and it's an essential fat, at that. That's a
great protein bargain.
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Caroline J. Cederquist, M.D. is a board certified Family Physician and a
board certified Bariatric Physicians (the medical specialty of weight management). She specializes in lifetime weight
management at the Cederquist Medical Wellness Center, her Naples, FL private practice, you can also
get more information about Dr Cederquist and her
weight management plan by visiting
www.DietToYourDoor.com
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