1. Useful Facts about Sugars, Starches, and Fiber
Unit 12

2. The Carbohydrates Carbohydrates
Chemical substances in foods that consist of a simple sugar molecule or multiples of them in various forms
Primary ingredient of staple foods (pasta, rice, cassava, beans, bread)

3. Three Types of Carbohydrates
Simple sugars
Complex carbohydrates (starches)
Total fiber

4. Carbohydrate Sources
Simple sugars (left), starch and fiber (right)

5. Carbohydrate Functions
Major source of energy
Recommended intake 45-65% of total calories
Simple sugars and complex carbohydrates supply 4 calories/gram
Dietary fiber indirectly supplies 2 calories/gram (when digested by bacteria in colon)
Other functions in immune and reproductive systems, blood clotting, DNA

6. Alcohol
Alcohol (ethanol) and alcohol sugars have similar structures

7. Simple Sugar Facts Simple sugars (sugars)
Carbohydrates that consist of a glucose, fructose, or galactose molecule, or a combination of glucose and either fructose or galactose
Also includes high-fructose corn syrup and alcohol sugars

8. Two Types of Simple Sugar
Monosaccharides
Consist of one sugar molecule
Glucose, fructose, galactose
Disaccharides
Consist of two monosaccharides linked together
Sucrose, maltose, lactose
Broken into monosaccharides by digestion

9. Disaccharides

10. Energy Production
Glucose is the only simple sugar the body can use to form energy
Fructose, galactose are converted to glucose
Excess glucose is converted to fat and glycogen
Body produces glucose by breaking down glycogen, amino acids, glycerol from fats
Cells in brain, blood, and kidneys require a constant supply of energy from glucose

11. Glycogen Glycogen Storage form of glucose Complex carbohydrate
Long chains of glucose molecules
Produced only by animals
Stored in liver and muscles

12. Body’s Sources of Glucose

13. Simple Sugar Intake
In US, total simple sugar intake averages 23% of total calories
17% of total calories from added sugars
Sucrose
High-fructose corn syrup

14. Simple Sugars in Foods Added sugars in candy, beverages, cereals
Natural sugars in milk, fruit, some vegetables

15. Nutrition Labeling of Sugars
Nutrition labels list total amounts of mono- and diglycerides per serving under “sugars”
All simple sugars must be listed in order of weight in the ingredients

16. Labeling Sugars

17. What’s So Bad About Sugar?
Simple sugars provide only calories
Sweetened foods are often high in fat, low in nutrients
Problems associated with high sugar intake:
Increased blood triglycerides
Excessive calorie intake
Tooth decay

18. Advice on Sugar Intake
Limit added sugars to 10% or less of total calorie intake

19. Alcohol Sugars Alcohol sugars (“polyols”) Examples:
Simple sugars containing an alcohol group in their molecular structure
Incompletely digested (~2 calories/gram)
Examples:
Xylitol, mannitol, sorbitol
Used as sweetening agents
Do not promote tooth decay

20. Products With Alcohol Sugars

21. Artificial Sweetener Facts
Artificial (non-nutritive) sweeteners
Not significant sources of energy or nutrients
160 to 13,000 time sweeter than sucrose
Do not promote tooth decay

22. Products with Artificial Sweeteners

23. Artificial Sweeteners

24. Artificial Sweeteners
Saccharin
First artificial sweetener (1800s)
300 times sweeter than sucrose
Aspartame (Nutrasweet)
Contains amino acids phenylalanine, aspartame
4 calories/gram
200 times sweeter than sucrose

25. Is Aspartame Safe?
Products containing aspartame must carry a warning for people with certain conditions
Phenylketonuria (PKU)
Genetic disorder
Lack of enzyme phenylalanine hydroxylase causes phenylalanine buildup in blood

26. Safe Limits for Aspartame
Safe levels of aspartame set at 50 mg/kg body weight/day
Some individuals report sensitivity to small amounts

27. Artificial Sweeteners cont.
Sucralose (Splenda)
Made from sucrose
600 times sweeter than sucrose
Acesulfame K (Sunette, Sweet One)
Acesulfame potassium
200 times sweeter than sucrose

28. Artificial Sweeteners cont.
Neotame
Like aspartame, made from phenylalanine and aspartame, but not harmful to people with PKU
7,000-13,000 times sweeter than sucrose
Rebiana (Reb-A, Truvia, Purevia)
Derived from herb stevia

29. Stevia-Based Sweeteners

30. Sweetness Rankings
Artificial and natural sweeteners, in order of sweetness

31. Complex Carbohydrate Facts
Complex carbohydrates
Form of carbohydrate found in starchy vegetables, grains, dried beans, and many types of dietary fiber
The most common form of starch is made of long chains of glucose units

32. Complex Carbohydrate Facts
Polysaccharides
Carbohydrates containing many molecules of monosaccharides linked together
3 major types: starch, glycogen, dietary fiber
Oligosaccharides
Polysaccharides consisting of 3 to 10 monosaccharides

33. Which Foods Have Carbohydrates?

34. Which Has More Calories?
4 oz baked potato
122 calories
3 oz lean hamburger
239 calories

35. US Fiber Facts
Fiber is low in calories, prevents constipation, and may lower risk of heart disease, obesity, and diabetes
Recommended intake grams/day
Fiber intake by US children and adults is low: about 15 grams of fiber/day

36. Good Sources of Fiber

37. Good Sources of Fiber

38. Types of Fiber
Edible fibers are classified based on source and effects on body processes
Functional fiber
Dietary fiber
Total fiber

39. Functional Fiber Functional fiber Effects:
Specific types of nondigestible carbohydrates that have beneficial effects on health
Examples: psyllium, pectin, gels, gums
Effects:
Feeling of fullness, slows glucose absorption, prevents constipation, decreases fat and cholesterol absorption

40. Dietary Fiber Dietary fiber
Naturally occurring, intact forms of nondigestible fiber in plants and “woody” plant cell walls
Contains nutrients and other plant substances
Found in oat and wheat bran; plant cellulose, fruits and vegetables, raffinose in beans

41. Dietary Fiber In Wheat Bran

42. Total Fiber
The recommended daily intake of fiber is based on total fiber
Total fiber
The sum of functional and dietary fiber

43. Soluble and Insoluble Fiber
Soluble fibers combine chemically with water
Found in oats, barley, fruit, psyllium
Slows glucose absorption
Reduces fat and cholesterol absorption
Insoluble fibers do not combine chemically with water
Found in bran, some legumes
Same health benefits as soluble fiber

44. Adding Fiber to Your Diet
Adding too much fiber to the diet too quickly can result in temporary side effects
Increase fluid intake along with fiber intake
Don’t add excessive fiber to children’s diets

45. Carbohydrates and Blood Glucose
Some types of simple and complex carbohydrates in foods elevate blood glucose levels more than others
Important to people with insulin resistance and type 2 diabetes

46. Key Terms Insulin resistance Type 2 diabetes
When cell membranes have reduced sensitivity to insulin, more insulin is required to transport a given amount of glucose into cells
Type 2 diabetes
High blood glucose levels due to the body’s inability to use insulin normally, or to produce enough insulin

47. Glycemic Index
Carbohydrate-containing foods are classified by how much they increase blood glucose
Glycemic index
Measure of how much blood glucose is raised by a 50-gram portion of a carbohydrate-containing food, compared to 50 grams of glucose or white bread

48. Glycemic Index of Foods
Some high glycemic-index foods:
Glucose, white bread, baked potatoes, jelly beans
Some low glycemic-index foods:
Fructose, xylitol, hummus, apples, all-bran cereal

49. Low Glycemic Index Diets
Diets with low glycemic index carbohydrates:
Improve blood glucose control
Reduce elevated blood cholesterol and triglycerides
Increase beneficial HDH cholesterol
Decrease risks of type 2 diabetes, some types of cancer, and heart disease

50. Carbohydrates and Your Teeth
Tooth decay did not become a problem until sugar became widely available
Tooth decay (dental caries, cavities)
Disintegration of teeth due to acids produced by bacteria in the mouth that feed on sugar

51. Sugars From Starchy Foods
Enzymes in the mouth break down starches into simple sugars
”Happy Tooth” symbol used in Europe to indicate foods safe for teeth

52. Tooth Decay: More Than Sugar
Stickiness and frequent consumption of sugary/starchy foods increases tooth decay
Eating sticky foods
Eating sugary foods between meals
Frequently sipping sweetened beverages
Chewing sugary gum

53. “Stickiness”

54. Sugar and Tooth Decay
Sugar feeds bacteria that live in the mouth and secrete acids that dissolve teeth
Plaque
Soft, sticky, white material on teeth
Formed by bacteria

55. Foods That Don’t Promote Decay

56. Water Fluoridation
Addition of fluoride to community drinking water supplies reduces the incidence of tooth decay by 50% or more
Fluoride is also added to toothpastes, rinses and gels, and to protective sealants

57. Baby Bottle Caries
Infants and small children who fall asleep while sucking a bottle may develop severe decay
Fluid pools around the upper front teeth