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Lecture Presentation Outline
I.
The Carbohydrates
 Carbohydrates are the major source of energy for people of the world
 Main component of staples - pasta, rice, cassava, beans, and bread
 We consume 51% of total calories as sugars
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Instructor Resources: Unit 12 Nutrition Scoreboard transparency master; Unit 12 PowerPoint
presentation on Multimedia Manager
A. Carbohydrate family has three types
1. Simple sugars
2. Complex carbohydrates (“starch”)
3. Total fiber
B. Features of Carbohydrates
1. Carbohydrates provide 4 calories/gm
2. Dietary fiber not digested by humans
3. Dietary fiber has roles in health
4. Alcohol sugars and alcohol are chemical relatives of carbohydrates
II. Simple Sugar Facts
 Simple sugars are small molecules
 Two types: monosaccharides and disaccharides
A. Monosaccharides:
1. Glucose (“blood sugar” or “dextrose”)
2. Fructose (“fruit sugar”)
3. Galactose
B. Disaccharides consist of two linked molecules
1. Glucose and a fructose make sucrose (or “table sugar”)
2. Glucose and a glucose make maltose (“malt sugar”)
3. Glucose and a galactose make lactose (“milk sugar”)
 Instructor Resources: Activity 12-1: Lactaid Milk
C. Features
1. Disaccharides are broken into monosaccharides during digestion
2. Only glucose, fructose, and galactose are absorbed into bloodstream
3. High-fructose corn syrup and alcohol sugars are also simple sugars
4. Most simple sugars have a sweet taste
 Instructor Resources: Activity 12-6: Sweeteners
D. Glucose
 Instructor Resources: transparency #35: Sources of Glucose
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The body uses glucose for energy
Fructose and galactose converted to glucose
The liver and muscles store glucose as the polymer glycogen
 Instructor Resources: transparency #34: Glycogen in a Liver Cell
a. Glycogen is chains of linked glucose units
b. When body needs energy, glycogen makes glucose available
4. Glucose can be derived from amino acids and the glycerol of fats
5. Cells require glucose as an energy source
6. Excess glucose is converted to fat
E. Where’s the Sugar?
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Instructor Resources: Activity 12-4: Sugar Content of Foods
Americans consume 84 grams of added sugar per day, about 17% of the average caloric
intake
Sugar consumption up 23% in past 30 years
Biggest source for many is soft drinks
Sucrose is added to other foods
a. Sugar is common ingredient of breakfast cereals
 Instructor Resources: Activity 12-2: Sugars in Breakfast Cereals
5.
F.
Simple sugars are in fruits and some vegetables
a. Fruits and vegetables provide many nutrients
6. Besides milk, animal products have no sugars
Added Sugars
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Instructor Resources: CNN Today Nutrition Vol. 2: Sugar Labels (1:50); Activity 12-3: Types of
Sugars
Sugar is added to food during food processing or preparation
Nutrition labels list total amount of sugar per serving
a. All simple sugars must be lumped together under “sweeteners” followed by a
parenthetical list itemizing each type in order of weight
b. Labels contain information on total sugars per serving and do not distinguish between
sugars naturally present in foods and added sugars
G. What’s So Bad about Sugar?
1. Foods with simple sugars are poor sources of nutrients
2. Simple sugars provide only calories
3. Many foods high in sugars are also high in fat
4. Likelihood diets will be insufficient in vitamins and minerals increases with sugar intake
5. Sweets consumption causes tooth decay
H. Sugar Fiction and Fact
1. Sugar has been falsely accused of:
a. Depleting the body of nutrients
b. Causing violent and criminal behavior
I.
c. Producing diabetes
d. Causing hyperactivity in children
2. Sugar actually:
a. Decreases kids’ activity level
b. Makes adults sleepy
c. Reduces appetite in the short-term
Advice on Sugar Intake
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Instructor Resources: Activity 12-8: How Many Treats Should You Have?
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J.
Enjoy sugars in limited amounts
a. DRIs say limit intake to below 25% of total calories
b. WHO and others recommend limiting added sugars to 10% of calories
2. Brush your teeth after eating sticky sweets
3. Replace regular soft drinks with water
What Are Alcohol Sugars?
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Instructor Resources: Activity 11 in Instructor’s Activity Book: Checking Out “Low-Carb” Food
Labels
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Alcohol sugars include a chemical component of alcohol
Alcohol sugars have a sweet taste
Xylitol is sweetest alcohol sugar, much sweeter than the other two, mannitol and sorbitol
Alcohol sugars are in small amounts in fruits
They are used to sweeten gums and candy
They do not promote tooth decay
III. Artificial sweetener facts
A. Why artificial sweeteners?
1. Unwanted calories in simple sugars
2. The connection of sucrose with tooth decay
3. Sugar substitute for people with diabetes
4. Sugar shortages
5. All provided incentives for developing sugar substitutes
B. Features
1. Artificial sweeteners in many prepared foods
2. None provide calories, promote tooth decay or raise blood glucose levels
3. None provide the taste qualities of sucrose
4. Whether artificial sweeteners lead to weight loss or prevention of weight gain is debated
a. Research results both support and refute a role for artificial sugars in weight loss
C. Saccharin
1. Saccharin was first artificial sweetener developed
2. It was discovered in the late 1800s
3. Saccharin 300 times sweeter than sucrose
4. Helped relieve sugar shortages during World Wars I and II
5. Saccharin taken off market when high doses caused cancer in lab animals
a. Saccharin was sole no-calorie sweetener available, its removal sparked public outcry
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b. Saccharin returned by Congress mandate
c. Saccharin was found safe in 2000, no clear evidence that it causes cancer in humans
Aspartame
1. Aspartame is 200 times sweeter than sucrose
2. Used in 4000 products worldwide, soft drinks, whipped toppings, jellies, cereals, puddings,
medicines
3. Products carry a label warning people with phenylketonuria (PKA) and others with liver
conditions about phenylalanine
a. PKA folks can’t use phenylalanine so it accumulates in blood
4. High temperatures break down aspartame, it is not used for heated products
5. Is Aspartame Safe?
a. Safe level defined as 50 mg/kg body weight per day in U.S. and 40 mg/kg body weight
per day in Canada
b. U.S. limit equals 20 aspartame-sweetened soft drinks or 55 desserts per day
c. Average intake in U.S., Canada, Germany, and Finland from 2 to 10 mg per day, safely
low
d. Claims of headaches, dizziness, or anxiety from small amounts not confirmed
Sucralose
1. Non-caloric sweetener from sucrose, safe and 600 times sweeter than sucrose
2. Does not leave a bitter aftertaste
3. Known as “Splenda” on product labels
4. Used in hot and cold food products, soft drinks, baked goods, frosting, pudding, and
chewing gum
Acesulfame Potassium
1. Acesulfame K, “Sunette” and “Sweet One”
2. It is added to 4000 foods in 90 countries
3. 200 times as sweet as sucrose
4. Provides zero calories
5. Does not break down when heated
FDA approved “neotame,” sweetener 7,000 times sweeter than sucrose
Cyclamate
1. Cyclamate widely used in U.S. up to 1960s
2. Banned in 1969 - large doses caused cancer in mice
3. Cyclamates available in over 50 countries
4. Several groups of experts have concluded that cyclamates are safe
IV. Complex Carbohydrate Facts
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Starches, glycogen, and dietary fiber are complex carbohydrates - polysaccharides
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Grains, potatoes, dried beans, and corn contain starch and dietary fiber, so are complex
carbohydrate sources
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Little glycogen in animal products

Instructor Resources: CNN Today Nutrition Vol. 3: The Lost Art of Baking (2:13)
A. Complex Carbohydrate Facts
1. Complex carbohydrates include whole grain breads, cereals, pastas, and crackers
2. Whole grain products provide more fiber than refined grain products
3. Whole grain foods reduce the risk of heart disease and some types of cancer
B. Dietary Fiber Facts

Instructor Resources: transparency #36: A Grain of Wheat; CNN Today Nutrition Vol. 2: Heart
Cereal (2:01); Activity 12-5: Fiber and Carbohydrate in the Pyramid; Handout 12-1: Food Guide
Pyramid; Activity 12-7: Increasing Dietary Fiber with Specific Food Choices
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Fiber intake in U.S. below the amount recommended
People get recommended amount from whole-grain breads, high-fiber cereal, and dried
beans and five servings of vegetables and fruits daily
Food sources same cooked, or raw
Fast foods are poor sources of fiber
Types of Fiber
a. Classification system for edible fibers is based on source
b. Fiber is not digested by human digestive enzymes
c. Fibers are classified as
1. Functional fiber
2. Dietary fiber
3. Total fiber
d. Functional fibers have beneficial functions in the body
1. Decrease food intake by a feeling of fullness
2. Reduce post-meal rises in blood glucose levels
3. Prevent constipation
4. Decrease fat and cholesterol absorption
e. Functional fiber is produced to fortify foods
f. Psyllium, pectin, gels, seed and plant gums, and meat connective tissues are functional
fibers
Be Cautious
a. High fiber diets cause diarrhea, bloating, and gas when too much fiber is added too
quickly
1. Bacteria in intestines use fiber and excrete gas
2. Gas causes bad feelings
b. Adding fiber gradually prevents side effects
c. Fluid intake should increase with dietary fiber
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V. Carbohydrates and Teeth

Instructor Resources: transparency #37: Diagram of a Healthy Tooth
A. Sugar and tooth decay related
1. Decay declined during WW I and II
2. Rebounded when sugar became available
3. Highest rates where sugar added to foods
4. Simple sugars come from starchy foods
5. Some countries have campaigns about cavity-promoting foods
B. Tooth decay prevention
1. Declines in tooth decay in U.S. from fluoride supplements, toothpastes, rinses and gels,
protective sealants, and improved dental hygiene and care
2. Lower rates of caries with reduced intake of sugars and sticky carbohydrates
3.
Fluoridation is safe, effective, and cheap
 Instructor Resources: Activity 12-9: Fluoride Opposition; Activity 12-10: Dental Health History
C. Baby Bottle Caries
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Instructor Resources: transparency #38: Baby Bottle Caries
Infants who fall asleep with a bottle (sugar water, milk, or formula) may develop severe
decay
Fluid collects, bathing teeth in sweet fluid for as long as the child sleeps
Foods with little carbohydrate or protein and high dietary fiber inhibit tooth decay