CarbohydratesBy Jennifer Turley and Joan Thompson

© 2016 Cengage

An Introduction to Carbohydrates: Presentation Overview

• 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

Simpleversus

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

• 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