Presentation is loading. Please wait.

Presentation is loading. Please wait.

The Carbohydrates Sugars Starches Fiber Copyright 2005 Wadsworth Group, a division of Thomson Learning.

Similar presentations


Presentation on theme: "The Carbohydrates Sugars Starches Fiber Copyright 2005 Wadsworth Group, a division of Thomson Learning."— Presentation transcript:

1

2 The Carbohydrates Sugars Starches Fiber Copyright 2005 Wadsworth Group, a division of Thomson Learning

3 Appendix B

4 Carbohydrates (CH 2 O) n Simple carbohydrates –Monosaccharides –C 6 H 12 O 6 Glucose Fructose Galactose –Disaccharides Complex carbohydrates Copyright 2005 Wadsworth Group, a division of Thomson Learning

5 Glucose Copyright 2005 Wadsworth Group, a division of Thomson Learning

6 Simplified Diagrams of Glucose The lines representing some of the bonds and the carbons at the corners are not shown. In this and other illustrations throughout this book, glucose is represented as a blue hexagon. Another way to look at glucose is to notice that its six carbon atoms are all connected. Now the single hydrogens are not shown, but lines still extend upward or downward from the ring to show where they belong.

7 Fructose & Galactose

8 Condensation Copyright 2005 Wadsworth Group, a division of Thomson Learning

9 Hydrolysis Copyright 2005 Wadsworth Group, a division of Thomson Learning

10 Disaccharides Maltose =____________ +____________ Sucrose =____________ +____________ Lactose =____________ +____________ Copyright 2005 Wadsworth Group, a division of Thomson Learning

11 Complex Carbohydrates Polysaccharides –Animal (Human) Polysaccharide Glycogen –Storage product in animals (Made up of glucose) –Enough storage for less than a day at rest or few hours of exercise –Synthesized in liver and muscle –Liver glycogen is available to the rest of the body but muscle tends to use its own glycogen (more in Ch. 7)

12 Complex Carbohydrates Polysaccharides (Plant) –Starches Storage product in plants Made up of glucose –Fibers Provides structure (rigidity) to stems, roots, leaves etc Made up of a variety of monosaccharides and other carbohydrate derivatives

13 Glycogen & Starch Molecules Compared (small Segments) Copyright 2005 Wadsworth Group, a division of Thomson Learning

14 Complex Carbohydrates Fibers (Structure) –Cellulose Made up of glucose Different type of bond –Hemicelluloses Found in Cereal Fibers Various monosaccharides –Pectins One type of monosaccharide Form gels Used to thicken jelly (jams) Copyright 2005 Wadsworth Group, a division of Thomson Learning Link cannot be broken by human digestive enzymes

15 Complex Carbohydrates Fibers –Gums and mucilages Guar Gum, Gum arabic (Gums) Psyllium, Carrageenan (Mucilages) –Lignin Carrots Seeds of strawberries –Resistant starches Whole legumes Raw potatoes Unripe bananas Copyright 2005 Wadsworth Group, a division of Thomson Learning

16 Complex Carbohydrates Fibers –Soluble fibers Viscous Fermentable –Insoluble fibers Nonviscous (Phytic acid) –Not classed as fiber –Reduces absorption of minerals (e.g. iron in cereals may not be absorbed well) Everything you want to know about fibre –http://www.nlm.nih.gov/medlineplus/dietaryfiber.htmlhttp://www.nlm.nih.gov/medlineplus/dietaryfiber.html –http://www.hsph.harvard.edu/nutritionsource/fiber.htmlhttp://www.hsph.harvard.edu/nutritionsource/fiber.html Copyright 2005 Wadsworth Group, a division of Thomson Learning

17 Fiber Fiber health benefit –Managing IBS ( normalizes bowel function i.e. keeps you regular –Shown to lower LDL ("bad") blood cholesterol levels, –Reduce the risk of heart disease, –Minimize colon cancer risks (This has been questioned recently) –Slow the absorption of fats and carbohydrates into the bloodstream, which »improves glycemic control »helps prevent the formation of free radicals. »lowers insulin requirements. Commercial fiber products –Acacia is gum arabic, Metamucil and Fybogel contain psyllium, Citrucel contains methylcellulose, Equalactin and Fibercon contains calcium polycarbophil, Benefiber contains guar gum, and FiberChoice contains inulin. Copyright 2005 Wadsworth Group, a division of Thomson Learning

18 Digestion Mouth –Salivary amylase Stomach –Fibers and satiety Small intestine –Maltase, sucrase, lactase Pancreas –Pancreatic amylase Large intestine –Fermentation of viscous fibers Water, gas, short-chain fatty acid production Copyright 2005 Wadsworth Group, a division of Thomson Learning

19 Digestion Available carbohydrates vs. unavailable carbohydrates (fiber) Copyright 2005 Wadsworth Group, a division of Thomson Learning

20 Carbohydrate Digestion in the GI Tract Copyright 2005 Wadsworth Group, a division of Thomson Learning

21 Absorption Copyright 2005 Wadsworth Group, a division of Thomson Learning

22 Lactose Intolerance Symptoms –Bloating, abdominal discomfort, diarrhea Causes –Lactase deficiency Prevalence –Less among Northern Europeans –More among Native North Americans and Southeast Asians Dietary changes –Does not require the elimination of milk/milk products –Can use fermented milk products Yogurt and Acidophilus milk Copyright 2005 Wadsworth Group, a division of Thomson Learning

23 Glucose in the Body Energy Glycoproteins Glycolipids Copyright 2005 Wadsworth Group, a division of Thomson Learning

24 Carbohydrate Metabolism Storing glucose as glycogen Using glucose for energy Copyright 2005 Wadsworth Group, a division of Thomson Learning

25 Complex Carbohydrates Polysaccharides –Animal (Human) Polysaccharide Glycogen –Storage product in animals (Made up of glucose) –Enough storage for less than a day at rest or few hours of exercise –Synthesized in liver and muscle –Liver glycogen is available to the rest of the body but muscle tends to use its own glycogen (more in Ch. 7)

26 Carbohydrate Metabolism Making glucose from protein –Gluconeogenesis –Protein-sparing action of carbohydrates Copyright 2005 Wadsworth Group, a division of Thomson Learning

27 Carbohydrate Metabolism Making ketone bodies from fat fragments –Ketone bodies Ketosis –Acid-base balance Copyright 2005 Wadsworth Group, a division of Thomson Learning

28 Carbohydrate Metabolism Converting glucose to fat –Energetically expensive Copyright 2005 Wadsworth Group, a division of Thomson Learning

29 Constancy of Blood Glucose Regulating hormones –Insulin –Glucagon –Epinephrine Copyright 2005 Wadsworth Group, a division of Thomson Learning

30 Maintaining Blood Glucose Homeostasis Copyright 2005 Wadsworth Group, a division of Thomson Learning

31 Constancy of Blood Glucose Diabetes –Type 1 diabetes Failure of insulin production –Type 2 diabetes Obesity Copyright 2005 Wadsworth Group, a division of Thomson Learning

32 Constancy of Blood Glucose Hypoglycemia –Rare in healthy people Copyright 2005 Wadsworth Group, a division of Thomson Learning

33 Constancy of Blood Glucose Glycemic response –Glycemic index Copyright 2005 Wadsworth Group, a division of Thomson Learning

34 Sugars Added sugars –Sucrose, invert sugar, corn syrups, etc. Health effects of sugars –Nutrient deficiencies Copyright 2005 Wadsworth Group, a division of Thomson Learning

35

36

37 Sugars Health effects of sugars –Dental caries Dental plaque Copyright 2005 Wadsworth Group, a division of Thomson Learning

38 Accusations Against Sugars Sugar causes obesity Sugar causes heart disease Sugar causes misbehavior in children and criminal behavior in adults DRI –No more than 25% of total daily energy intake Copyright 2005 Wadsworth Group, a division of Thomson Learning

39 Accusations Against Sugars Sugar causes cravings and addictions –serotonin Copyright 2005 Wadsworth Group, a division of Thomson Learning

40 Starch and Fiber Health effects –Heart disease –Diabetes –GI health Copyright 2005 Wadsworth Group, a division of Thomson Learning

41 Starch and Fiber Health effects –Cancer –Weight management –Harmful effects of excessive fiber intake Copyright 2005 Wadsworth Group, a division of Thomson Learning

42 Viscous Fibers Soluble and more fermentable Gums and mucilages Pectins Psyllium Some hemicelluloses Copyright 2005 Wadsworth Group, a division of Thomson Learning

43 Viscous Fibers Sources –Whole-grains, fruits, legumes, seeds and husks, vegetables –Extracted and used as food additives Copyright 2005 Wadsworth Group, a division of Thomson Learning

44 Viscous Fibers Lower blood cholesterol Slow glucose absorption Slow transit of food through upper GI tract Copyright 2005 Wadsworth Group, a division of Thomson Learning

45 Viscous Fibers Holds moisture in stools, softening them Yield small fat molecules that the colon can use for energy Copyright 2005 Wadsworth Group, a division of Thomson Learning

46 Viscous Fibers Lower risk of heart disease Lower risk of diabetes Copyright 2005 Wadsworth Group, a division of Thomson Learning

47 Viscous Fibers Copyright 2005 Wadsworth Group, a division of Thomson Learning

48 Nonviscous Fibers Insoluble and less fermentable Cellulose Lignins Psyllium Resistant starch Many hemicelluloses Copyright 2005 Wadsworth Group, a division of Thomson Learning

49 Nonviscous Fibers Sources –Brown rice, fruits, legumes, seeds, vegetables, wheat bran, whole grains –Extracted and used as food additives Copyright 2005 Wadsworth Group, a division of Thomson Learning

50 Nonviscous Fibers Increase fecal weight Speed fecal passage through colon Provide bulk and feelings of fullness Copyright 2005 Wadsworth Group, a division of Thomson Learning

51 Nonviscous Fibers Alleviate constipation Lower risks of diverticulosis, hemorrhoids, appendicitis May help with weight management Copyright 2005 Wadsworth Group, a division of Thomson Learning

52 Nonviscous Fibers Copyright 2005 Wadsworth Group, a division of Thomson Learning

53 Starch and Fiber RDA for carbohydrate –130 g/day –45% - 65% total daily energy intake Daily Value: 300 g/day Copyright 2005 Wadsworth Group, a division of Thomson Learning

54 Starch and Fiber Fiber –Daily Value: 25 g/day –AI: 14 g/1000 kcal/day Copyright 2005 Wadsworth Group, a division of Thomson Learning

55 Guidelines to Groceries Grains Copyright 2005 Wadsworth Group, a division of Thomson Learning

56 Guidelines to Groceries Vegetables Fruits Copyright 2005 Wadsworth Group, a division of Thomson Learning

57

58 Guidelines to Groceries Milk and milk products Meats and meat alternatives Copyright 2005 Wadsworth Group, a division of Thomson Learning

59 Alternatives to Sugar Artificial sweeteners vs. sugar replacers (nutritive sweeteners) Copyright 2005 Wadsworth Group, a division of Thomson Learning

60

61

62 Alternatives to Sugar Saccharine and cancer Aspartame and PKU Copyright 2005 Wadsworth Group, a division of Thomson Learning

63

64 Metabolism of Aspartame

65 Alternatives to Sugar Stevia Copyright 2005 Wadsworth Group, a division of Thomson Learning

66 Alternatives to Sugar Acceptable Daily Intake (ADI) Artificial sweeteners and weight control Copyright 2005 Wadsworth Group, a division of Thomson Learning

67

68 Sugar Alternatives on Food Labels


Download ppt "The Carbohydrates Sugars Starches Fiber Copyright 2005 Wadsworth Group, a division of Thomson Learning."

Similar presentations


Ads by Google