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Which of these has
the least carbohydrates?
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This roll of bread?
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This bowl of rice?
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Or this can of soda?
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It's a trick question.
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Although they may differ in fats,
vitamins, and other nutritional content,
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when it comes to carbs,
they're pretty much the same.
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So what exactly does that mean
for your diet?
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First of all, carbohydrate is
the nutritional category for sugars,
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and molecules that your body breaks down
to make suagrs.
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Carbohydrates can be simple or complex
depending on their structure.
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This is a simple sugar,
or monosacharide.
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Glucose, fructose,
and galactose are all simple sugars.
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Link two of them together,
and you've got a disaccharide,
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lactose, maltose, or sucrose.
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Complex carbohydrates,
on the other hand,
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have three or more simple sugars
strung together.
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Complex carbohydrates with three
to ten linked sugars
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are oligosaccharides.
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Those with more than ten
are polysaccharides.
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During digestion,
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your body breaks down those
complex carbohydrates
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into their monosaccharide building blocks,
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which your cells can use for energy.
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So when you eat
any carbohydrate-rich food,
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the sugar level in your blood,
normally about a teaspoon, goes up.
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But your digestive tract doesn't respond
to all carbohydrates the same.
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Consider starch and fiber,
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both polysaccharides,
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both derived from plants,
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both composed of hundreds to thousands
of monosaccharides joined together,
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but they're joined together differently,
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and that changes the effect
they have on your body.
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In starches, which plants mostly store
for energy in roots and seeds,
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glucose molecules are joined together
by alpha linkages,
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most of which can be easily cleaved
by enzymes in your digestive tract.
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But in fiber, the bonds between
monosaccharide molecules are beta bonds,
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which your body can't beak down.
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Fiber can also trap some starches,
preventing them from being cleaved,
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resulting in something called
resistant starch.
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So foods high in starch,
like crackers and white bread,
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are digested easily,
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quickly releasing a whole bunch of glucose
into your blood,
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exactly what would happen if you drank
something high in glucose, like soda.
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These foods have a high glycemic index,
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the amount that a particular food
raises the sugar level in your blood.
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Soda and white bread have a similar
glycemic index
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because they have a similar effect
on your blood sugar.
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But when you eat foods high in fiber,
like vegetables, fruits and whole grains,
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those indigestible beta bonds slow
the release of glucose into the blood.
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Those foods have a lower glycemic index,
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and foods like eggs, cheese, and meats
have the lowest glycemic index.
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When sugar moves from the digestive tract
to the blood stream,
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your body kicks into action to transfer it
into your tissues
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where it can be processed
and used for energy.
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Insulin, a hormone
synthesized in the pancreas,
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is one of the body's main tools
for sugar management.
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When you eat and your blood sugar rises,
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insulin is secreted into the blood.
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It prompts your muscle and fat cells
to let glucose in,
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and jump starts the conversion
of sugar to energy.
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The degree to which a unit
of insulin lowers the blood sugar
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helps us understand something called
insulin sensitivity.
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The more a given unit of insulin
lowers blood sugar,
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the more sensitive you are to insulin.
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If insulin sensitivity goes down,
that's known as insulin resistance.
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The pancreas still sends out insulin,
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but cells, especially muscle cells,
are less and less responsive to it,
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so blood sugar fails to decrease,
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and blood insulin continues to rise.
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Chronically consuming
a lot of carbohydrates
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may lead to insulin resistance,
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and many scientists believe
that insulin resistance
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leads to a serious condition
called metabolic syndrome.
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That involves a constellation of symptoms,
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including high blood sugar,
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increased waist circumference,
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and high blood pressure.
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It increases the risk
of developing conditions,
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like cariovascular disease
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and type II diabetes.
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And its prevalence is rapidly increasing
all over the world.
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As much as 32% of the population
in the U.S. has metabolic syndrome.
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So let's get back to your diet.
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Whether your food tastes sweet or not,
sugar is sugar,
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and too many carbs can be a problem.
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So maybe you'll want to take a pass
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on that pasta sushi roll pita burrito
donut burger sandwich.