Download presentation
Presentation is loading. Please wait.
Published byLoren Perry Modified over 9 years ago
1
PRESENTATIONS 9, 11, 16, 18, 23 MARCH
3
3 Carbohydrate/lipid/protein/alcohol 4/9/4/7 kcal/gram 17/37/17/29 kJ/gram Note alcohol = ethanol
4
4 Last time we talked about dietary carbohydrate in sports
5
5 Lecture 7 26 Jan. 2015 LIPIDS
6
6 OUTLINE OF LECTURE 7 1) LIPIDS DEFINED 2) STRUCTURES OF LIPIDS 3) LIPIDS IN FOODS 4) FUNCTIONS OF FATS IN FOODS 5) LIPID IDATME 6) FUNCTIONS OF LIPIDS ESSENTIAL OR NOT? HEALTHY AND UNHEALTHY METABOLISM
7
7 1)LIPIDS defined FAMILY OF COMPOUNDS THAT INCLUDES TRIGLYCERIDES (TG), PHOSPHOLIPIDS (PL) AND STEROLS OTHER DEFINITION WATER INSOLUBLE ORGANIC COMPOUNDS MADE UP OF C, H, AND O LIKE CARBOHYDRATES BUT LESS O AND THEREFORE 9 VS 4 KCAL/GM
8
8 2)STRUCTURES OF LIPIDS a)Triglycerides-fatty acids-structure, classification, in foods and function Structure Classification Organic acid Saturated 14:0 Monounsaturated 18:1 Polyunsaturated 18:2 n-6 18:3 n-3 18:3 n-6 (gamma-linolenic) 18:3 n-3 (alpha-linolenic) Glycerol Triglycerides Mixed triglycerides
9
9 REPLACE WITH FIG 5-2 ACETIC ACID Fig. 5-1, p. 140
10
p. 134
12
p. 135
16
16
17
17
18
18
19
Fig. 5-4, p. 137
20
20 TRIGLYCERIDES CONTINUED TRIGLYCERIDES IN FOOD Processed fat-fat manipulated mechanically or chemically Hydrogenation- -trans-fatty acids
21
Fig. 5-7, p. 138
22
Fig. 5-8, p. 139
23
23 FUNCTION OF FATTY ACIDS IN FOOD ESSENTIAL- LINOLEIC AND LINOLENIC
24
24 B) Phospholipids- structure, classification, in foods and function Structure- 2 FATTY ACIDS (FA) and polar head group-generally but exceptions Classification Choline-containing phospholipids Ethanolamine-containing phospholipids Phosphatidylserine Phospatidylinositol Sphingomyelin
25
Fig. 5-9, p. 140
26
26 PHOSPHOLIPIDS CONTINUED Foods- found naturally Function Membranes Lipoproteins Cell signalling
27
27 C) Sterols- structure, classification, in foods and function Structure-Ring structure Classification-Sterols
28
Fig. 5-11, p. 141
29
29 STEROLS CONTINUED Foods- found naturally-cholesterol vs phytosterol Function Membranes Lipoproteins Bile acids Hormones Vitamin D
30
30
31
31
32
32 3)Lipids in foods All lipid classifications we have discussed are in foods Animals and plants have free fatty acids, triglycerides, and phospholipids
33
33 LIPIDS IN FOODS CONTINUED Animal have cholesterols (free and cholesterol esters) Plants have phytosterols (free and esterified)
34
34 LIPIDS IN FOODS CONTINUED GRAINS BREADS/OATMEAL < 1 G FAT/SERVING CROISSANT 10 G FAT/MEDIUM VERY LITTLE FAT
35
35 LIPIDS in FOODS CONTINUED FRUITS AND VEGETABLES BOILED POTATO –TRACE HOMEMADE HASHBROWNS 11 G FAT/1/2 CUP APPLE 0.4 G FAT/MEDIUM AVOCADO15 G FAT/MEDIUM VERY LITTLE FAT OR NO FAT USUALLY
36
36 LIPIDS IN THE FOODS CONTINUED MILK, YOGURT AND CHEESE WHOLE MILK8 G/CUP REGULAR YOGURT4 G/CUP REGULAR CHEESE9 G/28G (1 OZ) GENERALLY MORE FAT THAN GRAINS, FRUITS AND VEGETABLES BUT CAN ALSO GET FAT FREE, REDUCED FAT AND WHOLE FAT VARIETIES
37
37 LIPIDS IN FOODS CONTINUED MEATS, POULTRY, FISH, PEAS, BEANS, LENTILS GENERALLY MORE FAT THAN MILK, YOGURT AND CHEESE BUT CAN ALSO GET LEAN MEATS CHUCK BLADE AND PORK 11 G/ 3 OZ (84 G) CHICKEN WITH SKIN 12 G/3 OZ (84 G) FISH – SALMON 5 G/3 OZ - COD 0.7 G/3 OZ NUTS 14-21 G/3 OZ
38
38 LIPIDS IN FOODS CONTINUED MODIFIED FOODS CARBOHYDRATE REPLACERS (PECTIN) PROTEIN REPLACERS (EG DERIVED FROM A CORN PROTEIN) FAT REPLACERS (EG OLESTRA)
39
39 LIPIDS IN FUNCTIONAL FOODS MARGARINES- BENECOL -BECEL-PRO-ACTIV -CORN OIL -FLAX OIL -CANOLA OIL CHICKEN FEED- OMEGA 3 AND OMEGA 6 FATTY ACIDS
40
40 LIPIDS IN FUNCTIONAL FOODS CONTINUED FISH CANOLA/FLAX SEA BUCKTHORN OIL- MIX OF OMEGA 3 AND OMEGA 6 FATTY ACIDS
41
Fig. 5-6, p. 138
42
42 4)FUNCTIONS OF FATS IN FOODS ABSORBING FLAVOURS AND AROMAS OF INGREDIENTS PROVIDING FLAVOUR OF ITS OWN CREAMY AND SMOOTH MOUTH TASTE TENDERIZING AND ADDING MOISTURE
43
43 5) LIPIDS IDATME
44
44 INGESTION OF LIPIDS MOUTH-CHEWING TUBE INTRAVENOUS
45
45 DIGESTION OF LIPIDS goal of fat digestion fats start out separated from enzymes in gi (gastrointestinal tract) -why? mouth digestion of fat-sublingual lipase-minor in adults -triglycerides
46
46 DIGESTION OF LIPIDS Small intestine -bile -pancreatic and intestinal lipases – triglycerides -phospholipases -sterols not digested Large intestine - no digestion of lipids
47
47 ABSORPTION OF LIPIDS small molecules short chain fatty acids medium chain fatty acids glycerol direct to blood larger molecules monoglycerides long chain fatty acids micelles formed in intestine micelles into intestinal wall cells chylomicrons formed and released into lymph file:///D:/Media/Animations/chapter5/Absorption_of_Fat/0517.html
48
48 TRANSPORT OF LIPIDS lipoproteins- chylomicrons (CM) (POST-PRANDIAL ONLY) - very low density lipoprotein (VLDL) - low density lipoprotein (LDL) - high density lipoprotein (HDL) - ALBUMIN density change due to 2 factors
49
49 LIPOPROTEIN METABOLISM Chylomicrons- made in small intestine – acted on by lipoprotein lipase in blood to give remnant particle which is taken up liver VLDL (very low density lipoprotein) made VIA LIVER VLDL acted on by lipoprotein lipase in blood to give remnant particle (intermediate density lipoprotein or IDL) which is taken up by liver- liver puts out low density lipoprotein (LDL) HDL ( high density lipoprotein) and albumin made by liver
50
Fig. 5-4, p. 137
52
FATTY ACIDS METABOLISED VIA KREB’S CYCLE TO GIVE LOTS OF ATP
53
53 LIPID EXCRETION -faeces-e.g. bile and undigested/unabsorbed lipid
54
54 6) FUNCTIONS OF LIPIDS- ESSENTIAL OR NOT?- HEALTHY AND UNHEALTHY METABOLISM
55
55 LIPIDS ESSENTIAL OR NOT ? YES-WHY ? HEALTHY ROLES
56
56 LIPIDS- ESSENTIAL OR NOT? YES - HEALTHY ROLES 1)INSULATION- HEALTHY ROLES Protective layer in body to help keep heat losses down
57
57 LIPIDS- ESSENTIAL OR NOT? YES HEALTHY ROLES 2)SUPPORT AND PROTECTION FOR INTERNAL ORGANS AND BONES Fat acts as support and cushioning for organs and cushioning for bones
58
58 LIPIDS- ESSENTIAL OR NOT? YES - HEALTHY ROLES 3)ABSORPTION OF FAT SOLUBLE VITAMINS Fat soluble vitamins cannot be absorbed without fat in the diet Why?
59
59 LIPIDS- ESSENTIAL OR NOT? YES - HEALTHY ROLES 4)CELL MEMBRANES Cholesterol and phospholipids are important in maintaining the structure and hence function of cell membranes What is a cell membrane?
60
60 LIPIDS- ESSENTIAL OR NOT? YES - HEALTHY ROLES 5) GIVES STRUCTURE TO MOLECULES Fatty acids give rise to triglycerides and phospholipids and cholesterol fatty acid complexes Structure of lipids in part dictates their function
61
61 LIPIDS- ESSENTIAL OR NOT? YES - HEALTHY ROLES 6)METABOLICALLY FAT STORED AS FAT- VERY EFFICIENT MAKING FAT FROM CARBOHYDRATE AND PROTEIN IS NOT VERY EFFICIENT ENERGY SOURCE-CAN STORE HUGE QUANITIES OF FAT
62
62 LIPIDS- ESSENTIAL OR NOT? YES - HEALTHY ROLES 7) IMPACT ON NUTRIENT ABSORPTION -GUT MOTILITY IS SLOWED -SLOWER RATE OF DIGESTION
63
63
64
64
65
65
66
66 FATS UNHEALTHY ROLES FAD DIETS NO FAT OR LESS THAN 10 % OF CALORIES AS LIPID IN DIET WITH ALL OR MOSTLY ALL OF ENERGY DIFFERENCE MADE UP WITH CARBOHYDRATE AVOID !!!
67
67 UNHEALTHY ROLES FAT TO FAT- OBESITY -OBESITY- TOUGH ON JOINTS, -MAY CONTRIBUTE TO ARTHRITIS -ELEVATES BLOOD PRESSURE- WHICH MAY GIVE ATHEROSCLEROSIS AND HEART ATTACKS AND STROKE
68
68 UNHEALTHY ROLES OBESITY CONTINUED -ELEVATES FREE FATTY ACIDS IN THE BLOOD WHICH MAY GIVE INSULIN RESISTANCE -IF EXCESS FAT IN THE DIET THIS MAY CROWD OUT OTHER NUTRIENT CLASSES
69
69 SUMMARY OF LECTURE 7 1) LIPIDS DEFINED 2) STRUCTURES OF LIPIDS 3) LIPIDS IN FOODS 4) FUNCTIONS OF FATS IN FOODS 5) LIPID IDATME 6) FUNCTIONS OF LIPIDS ESSENTIAL OR NOT? HEALTHY AND UNHEALTHY METABOLISM
70
70 NEXT TIME DIETARY LIPIDS IN SPORTS
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.