Breakfast -How Not To Start The Day Part II
The Order of Energy Utilization
Back to our table of stored energy in an average 70 kg man.
Organ ************** Available energy (kcal)
************ glucose/glycogen ***** fat ****** protein
blood *********** 60 ************** 45 ******* 0
liver *********** 400 ************* 450 ****** 400
brain *********** 8 *************** 0 ******** 0
muscle ********** 1200 ************ 450 ****** 24000
adipose(fat) **** 80 ************** 135,000 ** 40
from Stryer Biochemistry 4th Edition page 771
Glucose and Glycogen 1600 kcal of available energy
As you can see from the table above, there are three categories
of energy. Glucose and glycogen (a polymer of glucose) is the
first category and the most readily available. This is the
energy that most of us utilize most of the day. The human
body needs plentiful supplies of glucose, especially since it
is basically the only molecule that the brain can metabolize.
Good sources of real complex unprocessed carbohydrates are
grains, potatoes and rice.
Protein 24000+ kcal
The human body can process protein to make glucose via a
pathway called gluconeogenesis. During periods of starvation
the protein / lean body mass of the body can be catabolized
to provide glucose for the brain. This is not a good way
however, to lose weight as you are losing what you don't
want to lose -lean body mass. As you can see from the chart
most of the protein available for energy utilization comes
Fat 135,000 kcal available stored energy
By far the most stored energy the human has is in fat.
However, it is also the last energy source the body will
turn to unless the requisite enzyme systems are already in
place to process the fat. One of the advantages of the
fat burning system is that you don't have to be starving
to have it supply glucose for your brain or your muscles.
You do, however, have to have trained your metabolism
sufficiently so that when you call on this "fat burning"
system, it will be able to proceed at a rate fast enough
(have enough enzymes present) to supply enough glucose to
Running and learning to burn fat
Long distance running has long been an area of "fat burning."
As mentioned previously, most humans can store about 20 miles
of energy from glycogen / glucose sources. After about twenty
miles most humans will switch to fat burning. What has to be
understood here is that the rate of your fat burning will be
dependent on how much you trained in a glucagon / fat burning
/ energy utilization state. Even if you have trained a lot
this way you may still slow down when you switch but the
slow down will not be as severe as if you have not trained
your metabolism at all. If you haven't trained your metabolism
at all, you will probably be walking the last six miles.
How to learn to burn fat ...
In order for your body to be able to burn fat, you have to
enter a glucagon state -period. There is no other way. You
cannot be eating six, seven or eight meals a day. If fact,
it is very hard to learn to burn fat if the first thing you
do every day is eat a big breakfast. You wake up ready to
go glucagon for a while and the first thing you do is ... eat
breakfast. Up goes your insulin, down goes your glucagon.
Your stomach empties in usually about thirty minutes and then
you are hungry again. You wait till about ten in the morning
have a snack and just about the time your insulin levels are
starting to come down -up they go again. The cycle repeats
itself all day.
Timing and hunger ...
The stomach usually empties in thirty minutes. Usually it
takes two to three hours for the blood sugar to return to normal
and the insulin levels to begin to return to fasting levels.
This is one of the real problems with the human body. The
biochemistry of energy metabolism is at least 100,000 years
old with power of hunger -also 100,000 years old. However,
100,000 years ago there was no way to eat every time we
got hungry. Today we eat at the slightest twinge of hunger,
often eating heavily processed sugar packed foods with no
The incomplete food hunger cycle
Because there is no nutritional value in most if not all
of the foods in your average local "super"market, the food
does not turn off your hunger. As soon as your stomach
empties, you are eating something else, always trying to
satisfy the hunger. Since the hunger can never be satisfied,
you keep eating and eating. Soon you are completely encased
in fat, feel terrible and your risk of serious disease just skyrockets.
What you can do ...
Never eat before you expend some energy is some form in the
morning. I accomplish this by running usually seven miles.
When I first quit eating anything before I ran, the first few
runs were a bit weak. I didn't feel good at about forty-five
minutes into the run and would even feel a bit light-headed
and hypoglycemic. I persisted and in about two weeks these
feelings were completely gone and I could cruise an easy two
hours with no additional fuels. The point here is that you
have to enter into a glucagon state, start training your
metabolism / enzyme systems and soon they will be able to
supply the necessary energy for your run and you will be
Don't fill your tanks before you have emptied them and
then some ...
At some point in every day -spend some time in a glucagon
state. That is the human biochemistry. To use the car
analogy again think of filling your tank with gas, every
day -the same amount. Each day you fill your gas tank with
fifteen gallons of fuel. Some days you drive to Phoenix and
back and use all this gas, but most days you just drive
to the grocery and back. The next day you go for your
fifteen gallons and you can only get five gallons in your tank.
You put the other ten in two five gallon containers and put them
in the trunk.
Your car is full of gas -and you can't drive around the block
The next day you drive to the cleaners and then stop to
fill up again. Another fifteen gallons and this time
you have to put twelve of them into separate containers.
Now the trunk is full of gas containers and weighting down
your car. Soon the back seat if full, the front seat is full
and there is barely any room for you, the driver. If you
don't expend the ingested energy, insulin will store it for
you -somewhere and everywhere in and on your body. Learn to
go a little beyond your ingested energy and keep those fat
burning pathways open. You will feel better, work better
and really reduce your risk of disease.
Thanks for your attention.
Copyright © John Mericle M.D. 2005 All Right Reserved
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