Lipids by answekkkkkkkkkkkr ali lec.pptx

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1. The Lipids: Triglycerides, Phospholipids, & Sterols Chapter 5 Anwar A Shad 4/25/2024 10:19 PM Lipids: Chemistry and Nutritional Significance 1

2. Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 2

3. Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 4

4. Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 6 Numbering of carbon atoms. The systematic (IUPAC) C- x numbers are in blue. The ω− x " labels are in red. The Greek letter labels are in green. Note that unsaturated fatty acids with a cis configuration are actually "kinked" rather than straight.

5. Omega- 3 and Omega- 6 Fatty Acids Compared Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 7

6. Triglycerides Three fatty acids attached to a glycerol Formed via series of condensation reactions Usually contain mixture of fatty acids Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 8

7. Condensation of Glycerol and Fatty Acids to Form a Triglyceride Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 9

8. Diagram of Saturated and Unsaturated Fatty Acids Compared Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 10

9. Illustration of Hydrogenation Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 11

10. Cis - and Trans - Fatty Acids Compared Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 12

11. Phospholipids Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 13 Spingomyelins Phosphatidylcholine Phosphatidyl ethanolamine Phosphatidyl serine Phosphatidyl inositol Plasmalogens Cardiolipins

12. Lecithin Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 14

13. Phospholipids participate in the reverse cholesterol transport and thus help in the removal of cholesterol from the body. Phospholipids act as surfactants (agent lowering surface tension). Cephalins participat in blood clotting . Phospholipids( phosphatidyl inositoal ) involved in signal transmission across membranes.

14. Sterols Food sources Cholesterol Plant sterols Roles of sterols Made in the body Structural component of cell membranes Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 16

15. Cholesterol Related compounds : 7-dehydrocholesterol (functions as a cholesterol precursor in blood serum) gets converted in vivo (epidermal cells) to Vitamin D by the action of sunlight Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 17

16. Fat Digestion in the GI Tract Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 18

17. Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 19

18. Lipid Digestion in the Small Intestine Lipids: Chemistry and Nutritional Significance Cholecystokinin (CCK) Gall bladder releases bile Bile acts as emulsifier Pancreatic lipase Hydrolysis Triglycerides and phospholipids Bile routes Effect on blood cholesterol levels 4/25/2024 10:19 PM 20

19. Emulsification of Fat by Bile Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 21

20. Stepped Art - Fat Watery GI juices Fat In the stomach, the fat and watery GI juices tend to separate. The enzymes in the GI juices can’t get at the fat. When fat enters the small intestine, the gallbladder secretes bile. Bile has an affinity for both fat and water, so it can bring the fat into the water. Bile’s emulsifying action converts large fat globules into small droplets that repel each other. After emulsification, more fat is exposed to the enzymes, making fat digestion more efficient. Enzyme Emulsified fat Bile Enzymes Emulsified fat Emulsified fat 4/25/2024 10:19 PM Lipids: Chemistry and Nutritional Significance 22

21. Hydrolysis of a Triglyceride Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 23

22. Enterohepatic Circulation Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 24

23. Lipid Absorption Lipids: Chemistry and Nutritional Significance Directly into bloodstream Glycerol and short- and medium- chain fatty acids Lymphatic system Micelles diffuse into intestinal cells Reassembled into triglycerides Packed with proteins into transport vehicles called chylomicrons Bypass liver at first 4/25/2024 10:19 PM 25

24. Absorption of Fat Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 26

25. Lipid Transport Lipids: Chemistry and Nutritional Significance Four main types of lipoproteins Chylomicrons Largest and least dense Transport diet- derived lipids Liver removes remnants from blood Very-low- density lipoproteins (VLDL) Made in the liver Proportion of lipids shifts 4/25/2024 10:19 PM 27

26. Lipoprotein Types Lipids: Chemistry and Nutritional Significance Low- density lipoproteins (LDL) Cell needs Liver regulation High- density lipoproteins (HDL) Remove cholesterol from cells Carry cholesterol to liver for recycling Anti- inflammatory properties Health implications 4/25/2024 10:19 PM 28

27. Sizes and Compositions of the Lipoproteins Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 29

28. Lipid Transport via Lipoproteins Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 30

29. Roles of Triglycerides Lipids: Chemistry and Nutritional Significance Provide the cells with energy Virtually unlimited ability to store fat energy Adipose tissue stores body fat Secretes hormones (adipokines) Other uses of fat in the body Skin insulation Shock absorption Cell membrane material Cell signaling pathways 4/25/2024 10:19 PM 31

30. An Adipose Cell Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 32

31. Essential Fatty Acids Must be supplied by the diet Linoleic acid Linolenic acid Can be used to make other fatty acids Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 33

32. Omega- 6 and Omega- 3 Fatty Acids Lipids: Chemistry and Nutritional Significance Linoleic acid – Omega- 6 fatty acid Sources: vegetable oils and meats Linolenic acid – Omega- 3 fatty acid Cannot be made in the body Must be supplied by food DHA EPA 4/25/2024 10:19 PM 34

33. Eicosanoids Lipids: Chemistry and Nutritional Significance Eicosanoids “Hormonelike” Health benefits Omega- 6 to Omega- 3 ratio Fatty acid deficiencies Rare in the United States and Canada Symptoms 4/25/2024 10:19 PM 35

34. A Preview of Lipid Metabolism Lipids: Chemistry and Nutritional Significance Adipose cells store fat after meals Lipoprotein lipase Hydrolyzes triglycerides Triglycerides reassembled inside adipose cells Using fat for energy Fat supplies 60 percent of energy needs during rest Energy deprivation Fasting: fat and lean protein tissue used for energy 4/25/2024 10:19 PM 36

35. Health Effects of Saturated Fats, Trans Fats, and Cholesterol Lipids: Chemistry and Nutritional Significance Current American diet Excessive amounts of solid fats Blood lipid profile Heart disease Elevated LDL cholesterol a risk factor Saturated fats increase LDL cholesterol, promote blood clotting Dietary choices Trans fats – increase LDL cholesterol Dietary cholesterol 4/25/2024 10:19 PM 37

36. Fat Links to Cancer and Obesity Lipids: Chemistry and Nutritional Significance Cancer Dietary fat and cancer risk Differs for various types of cancer Promotion rather than initiation of cancer Obesity Cutting fat from diet reduces kcalories Dietary recommendations 4/25/2024 10:19 PM 38

37. Recommended Intakes of Saturated Fat, Trans Fat, and Cholesterol Lipids: Chemistry and Nutritional Significance DRI and Dietary Guidelines 20 to 35 percent of daily energy from fat Less than 10 percent of daily intake from saturated fat As little trans fat as possible Less than 300 mg cholesterol Avoid getting too little fat Recommendation: one teaspoon of fat with every meal 4/25/2024 10:19 PM 39

38. Health Effects of Monounsaturated and Polyunsaturated Fats Heart disease Replace saturated fats with unsaturated fats Regular consumption of omega- 3 fatty acids Suppresses inflammation Cancer Omega- 3 fatty acids from food Supplements Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 40

39. Replacing Saturated Fat with Unsaturated Fat Lipids: Chemistry and Nutritional Significance Portion sizes have been adjusted so that each of these foods provides approximately 100 kcalories. Notice that for a similar number of kcalories and grams of fat, the second choices offer less saturated fat and more unsaturated fat. Replace these foods… Saturated Fat (g) Unsaturated Fat (g) Total Fat (g) Butter (1 tbs) 7 4 11 Bacon (2 slices) 3 6 9 Potato chips (10 chips) 2 5 7 Cheese (1 slice) 4 4 8 Steak (1'/2 0z) 2 3 5 Totals 18 22 40 …with these foods Saturated Fat (g) Unsaturated Fat (g) Total Fat (g) Olive oil (1 tbs) 2 9 11 Sunflower seeds (2 tbs) 1 7 8 Mixed nuts (2 tbs) 1 8 9 Avocado (6 slices) 2 8 10 Salmon (2 oz) 1 3 4 Totals 7 35 42 4/25/2024 10:19 PM 41

40. Recommended Intakes of Mono- and Polyunsaturated Fats Lipids: Chemistry and Nutritional Significance 20 to 35 percent of kcalories from fat Includes essential fatty acids AI have been established DRI Linoleic acid: 5-10% of daily energy Linolenic acid: 0.6- 1.2% of daily energy 4/25/2024 10:19 PM 42

41. Selecting Groceries Lipids: Chemistry and Nutritional Significance Fat- soluble vitamins A, D, E, and K Flavor, texture, and palatability Protein foods Selections Milk and milk products Selections 4/25/2024 10:19 PM 43

42. Cutting Fat Cuts kCalories and Saturated Fat Lipids: Chemistry and Nutritional Significance 4/25/2024 10:19 PM 44

43. Grocery Choices Lipids: Chemistry and Nutritional Significance Vegetables, fruits, and grains Lowers consumption of various fats in the diet Provides phytochemicals Solid fats and oils Fried and baked goods Choose wisely Unprocessed foods 4/25/2024 10:20 PM 45

44. Food Labeling Lipids: Chemistry and Nutritional Significance Total fat, saturated fat, trans fat, and cholesterol Compare products Percent Daily Value versus percent kcalories from fat Fat replacers Types Risks 4/25/2024 10:20 PM 46

45. High- Fat Foods – Friend or Foe? Highlight 5 Lipids: Chemistry and Nutritional Significance 4/25/2024 10:20 PM 47

46. Guidelines for Fat Intake Lipids: Chemistry and Nutritional Significance Limit saturated fat and trans fat intake Moderate kcalories Enough fat for good health Not too much of the harmful fats DRI recommendations Compatible with low rates of disease 4/25/2024 10:20 PM 48

47. High- Fat Foods and Heart Health Lipids: Chemistry and Nutritional Significance Olive oil Benefits for heart health Replace saturated fats Nuts LDL cholesterol Fat composition Benefits for heart health Cautious advice for dietary inclusion 4/25/2024 10:20 PM 49

48. Fish Lipids: Chemistry and Nutritional Significance Omega- 3 fatty acids Benefits for heart health Environmental contaminants Farm raised versus wild Dietary recommendations 4/25/2024 10:20 PM 50

49. High- Fat Foods and Heart Disease Lipids: Chemistry and Nutritional Significance Saturated fat the top dietary determinant of LDL cholesterol Sources of saturated fat in the U.S. Meats Whole milk products Tropical oils Zero saturated fat is not possible Trans fat Limit hydrogenated foods 4/25/2024 10:20 PM 51

50. Two Meals Compared Lipids: Chemistry and Nutritional Significance 4/25/2024 10:20 PM 52

51. The Mediterranean Diet Lipids: Chemistry and Nutritional Significance Features of a traditional Mediterranean diet Low in saturated fat Very low in trans fat Rich in monounsaturated and polyunsaturated fat Rich in complex carbohydrate and fiber Rich in nutrients and phytochemicals Benefits for heart disease risk 4/25/2024 10:20 PM 53

52. Mediterranean Diet Pyramid Lipids: Chemistry and Nutritional Significance 4/25/2024 10:20 PM 54