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What Is Obesity?
Nearly everyone today worries about being overweight. We're
constantly inundated with messages from TV and the Internet
about widespread obesity and the risks of being obese. Whether
it's health issues or social acceptance, no one wants to be
fat!
But if you look at it from an evolutionary aspect, the ability
to store excess calories in the form of fat cells is a very
life-serving ability. When a person consumes more calories than
the body uses for muscle movement, internal temperature
maintenance and cellular repair the remainder is stored in the
chemical bonds of fat cells. Technically, it's stored in
something called 'adipose tissue'.
Energy - which calories measure - isn't a substance, so it's
not the same as fat. But that energy becomes available for use
when those fat molecules break down into simpler products. That
happens when a person increases movement or otherwise triggers
a need for more energy.
Carbohydrates are one major source of that energy. Sugars
(chiefly glucose) and starches are the two main forms and they
participate in something called the Krebs Cycle. Also known in
scientific circles as the tricarboxylic acid cycle, but don't
bother trying to pronounce it. Sugars come in, get broken down
into something called ATP, then into ADP releasing energy in
the process.
When the body runs out of glucose to use in the cycle, it turns
to stored body fat as a substitute. Breaking down those fat
molecules is, in essence, what causes a person to decrease the
percentage of body fat. Sometimes increased muscle mass
results, so the final result isn't always a net weight
loss.
But in biology, as in life, everything is best in moderation.
When more calories are consumed than used over a long period of
time, body fat increases to the point that the health risks can
outweigh the benefits of a ready supply of energy. The result
is an increase in the odds of heart difficulties, diabetes and
other real medical problems. The social consequences are
equally well known.
Knowing this, many will strive to maintain their weight and
percentage of body fat within a certain range. That range
differs from person to person (people have different body
types), season to season (winter fat can actually be healthy)
and according to their individual BMI (Body Mass Index).
So, in order to decide whether you are obese, only moderately
over the preferred weight range, or just lack muscle tone, you
need to consider those factors. Doing so requires knowing your
specific body type, the ability to calculate BMI (very simple,
actually) and recognizing that there is no exact, static, ideal
weight for you.
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