We often discuss energy savings at WattBusters but how often do we think about
the ways that fuel is converted to energy. Natural gas to heat, coal to
electricity, sugar into screaming, bouncing children, etc. Since
it's close to Halloween and candy will probably be fairly abundant around the
house, let's zero in on sugar.
Sugar is technically a form of carbohydrates and carbohydrates are good for
you, as long as you eat the right kinds in the right amounts. Carbohydrates are
your body's main source of energy. But before you reach for the
carbs in a candy bar, take some time to learn about sugar. Babies are born
with a sweet tooth. Human milk is quite sweet, so a child begins life
making the connection between eating, drinking, and pleasure.
Over-processed, factory-made sugars have given carbohydrates a bad
reputation. To understand why these sugars merit the label
"junk sugars," let's take a ride with these sugars from the mouth
to the bloodstream to see how they affect the body.
Junk sugars are called simple carbohydrates because they are short,
uncomplicated molecules. Because simple sugars are already so small,
they require little or no breaking down in the intestines. The sucrose
molecule is quickly broken down into glucose and fructose, and all that
glucose is actively pumped through the intestinal cells quickly into the
bloodstream. A sprinkle of sugar that hits the intestines enters the
bloodstream almost immediately, and the roller coaster ride begins.
After the refined sugars rush into the bloodstream, blood sugar levels rise,
pressuring the pancreas to release insulin, the hormone needed to escort
these sugars into the body's cells. Lots of insulin helps the sugar get
used up rapidly, but then the blood sugar level plunges. The body hits
a sugar low, also known as hypoglycemia or "sugar blues." Now, just as
insulin was released when the blood sugar was too high, other hormones
are released when the blood sugar is too low. These stress hormones
want to restore the blood sugar to normal levels, so they squeeze stored
sugar from the liver, sending the blood sugar back up. These adjustments
work better in some people than in others and better in some circumstances
than others.
A study comparing the sugar response in children and adults showed that the
adrenaline levels in children remained ten times higher than normal for up
to five hours after a test dose of sugar. The general consensus is
that some children and adults are sugar-sensitive, meaning their behavior,
attention span, and learning ability deteriorate in proportion to the amount
of junk sugar they consume.
The energy of foods, as often printed on food packages, is measured in
calories --"big" calories or kilo-calories, each equal to 4180 joule.
What's a joule? A joule is equal to the kinetic energy of a two-kilogram
mass moving at the speed of one meter per second. OK... That's way too
scientific and I don't think we want to go there. Joules were named after an English
brewer so we can assume we started off with 'happy' science. Scientists
measure work (a force acting over a distance) in joules. The point of
all of this is, if
we know the calories, we can convert to joules and calculate how much energy
in each calorie.
Carbohydrates give about 4 calories per gram. Fats and oils are a different
family and contain about 9 calories per gram. And proteins, give a net
gain of about 4 calories per gram, after one subtracts the energy needed for
their break-up from the amount they can supply. According to NASA
chemical energy formulas utilizing calories, weight and gravity, the
energy of one calorie is enough to raise a 154 pound person by about 19.5
feet. Of course, if the efficiency of converting the chemical energy of
food to muscle energy is only 10%, the person would only rise about 2 feet.
Still, a typical American may consume 3000 calories per day, enough fuel
for quite a bit of climbing.
Sugar (a carbohydrate) gives about 4 calories per gram. Interestingly,
the explosive TNT--trinitrotoluene--only releases 3.8 calories per gram.
Its energy release may be extremely sudden, but in magnitude it falls below that
of sugar. So this Halloween, while giving new meaning to the words
'sugar bomb' you may finally understand why the kids are bouncing off walls.
