Carbohydrates
By Jennifer Turley and Joan Thompson
© 2016 Cengage
An Introduction to Carbohydrates:
Presentation Overview
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Composition
Energy Yield
Categories
Food Source
Dietary Recommendations
Alcohol
Carbohydrates
(Carbs or CHO)
• Composition: Carbohydrate is
made of the elements carbon,
hydrogen, and oxygen.
• Organic Compound: Carbohydrate
is organic because it contains
carbon. It is a compound because it
has more than one element in its
structure.
• The ratio of Carbohydrate is
CxH2x0x.
• 1 C6H1206 + 6O2 <=> 6C02 + 6H2O
Carbohydrates: Energy
Yield
• Provides 4 Calories/gram.
• It is the most preferred fuel for
the body.
• It is high performance fuel.
• It produces ATP at the fastest
rate.
Categories of
Carbohydrates
Simple
versus
Complex
Simple Sugars:
Monosaccharides
α-D-Glucose
β-D-Fructose
β-D-Galactose
Disaccharides
α-Sucrose
α-Maltose
β -Lactose
Common Names of
Sugars
– Glucose is blood sugar
– Fructose is fruit sugar
– Sucrose is table sugar
– Lactose is milk sugar
– Maltose is malt sugar
Complex Carbohydrates,
Part 1
Polysaccharides:
Starch (digestible & caloric)
– Alpha linked glucose molecules in
starch can be broken apart by the
enzyme alpha-amylase to produce
energy.
– The glucose units that are released
are absorbed into the blood stream.
Complex Carbohydrates,
Part 2
Polysaccharides:
Fiber (indigestible & noncaloric)
– Beta linked glucose molecules
cannot be broken apart by human
enzymes so no energy is produced.
– The glucose units are not released
and thus fiber is not absorbed.
– Cellulose is the most common type
of fiber.
Polysaccharides
Food Sources of
Carbohydrates
• Grains, Cereals, &
Legumes: Pasta, bread,
cold/hot cereal, rice, oats,
kidney beans, etc.
• Fruits & Vegetables
• Starchy Vegetables: Corn,
potato, peas, acorn squash,
etc.
Plant Sources of
Carbohydrates
• Simple carbohydrates:
Fruit, table sugar, sweets &
sugar sweetened cereals.
• Complex carbohydrates:
Vegetables, starchy
vegetables, grains,
legumes, & whole grain
cereals.
Animal Food Sources of
Carbohydrates
• Milk (& milk products yogurt &
cheese) contain lactose.
• Honey contains glucose, fructose &
small amounts of other sugars.
• Animal foods usually provide
mostly proteins & fats.
• Milk & milk products also provide
proteins & varying amounts of fats.
How much carbohydrate do
you need?
The Acceptable Macronutrient Distribution Range (AMDR) is:
45-65% of Calories from carbohydrates
≤ 25% of Calories
from sugars
How much fiber do you need?
The dietary recommendation for fiber is
1.4 gram per 100 Calories consumed
Alcohol: Carbohydrate like & Drug
Alcohol: CH3CH2OH
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Provides 7 Calories/gram.
Is a carbohydrate related substance.
Lacks nutritional value.
Is a central nervous system (CNS) depressant.
Is considered a drug.
Is commonly ingested.
One serving per day may reduce
heart disease risk but increase
cancer risk.
Some
Summary Points
• Organic compounds categorized as: simple &
complex.
• They provide 4 Calories/gram; except fiber is
non-caloric.
• They are the preferred fuel of the body.
• Consume 45-65% of Calories from digestible
carbohydrates; ≤ 25% Calories from added
sugars; 1.4 grams fiber per 100 Calories
consumed.
• Found in plant foods, except animal sources of
milk & honey.
• Alcohol is a carbohydrate-like drug providing 7
Calories/gram
References for this presentation are the same as those for this topic found in module
1 of the textbook