1. Chapter 5
Lipids

2. What Are Lipids? Hydrophobic/hydrophilic Lipophilic/lipophobic
Classes of lipids
Triglycerides
Phospholipids
Sterols
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3. Fatty Acids Are Key Building Blocks
Chain Length
4–24 carbons

4. Fatty Acids Are Key Building Blocks
Saturation
Saturated
All single bonds between carbons
Monounsaturated
One carbon-carbon double bond
Polyunsaturated
More than one carbon-carbon double bond

5. Fatty Acids Are Key Building Blocks
Geometric and Positional Isomers
Cis fatty acid
Trans fatty acids
Hydrogenation
Conjugated linoleic acid

6. Fatty Acids Are Key Building Blocks
Types of fatty acids
Omega-3
Omega-6
Omega-9

7. #6 Triglycerides Structure Functions Glycerol + 3 fatty acids
Energy source
Energy reserve
Insulation and protection
Carrier of fat-soluble compounds
Sensory qualities in food

8. Function of Triglycerides
Fat performs a number of essential functions in the body.
Fat is also a major energy source. When at rest, muscles prefer to use fat for fuel.

9. Triglycerides in Food Sources of omega-3 fatty acids
Soybean, canola, walnut, flaxseed oils
Salmon, tuna, mackerel
Sources of omega-6 fatty acids
Vegetable oils
Nuts and seeds
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10. #2 Fat vs Oil Fat – solid at room temp Oil – liquid at room temp
Butter, Lard, Crisco, Coconut oil
Olive oil, canola oil

11. #3 Fatty acids
Saturated fatty acid – full saturated with hydrogen, solid fats
Monounsaturated – one double bond, liquid oil
Polyunsaturated – two or more double bonds, liquid oil
Trans fatty acid – lab made fat, solid fat like crisco

12. # 4 Essential Fatty Acids
Characteristics of Omega 3 and 6
Essential (EFA)- Have to consume in diet
Unsaturated fats
Deficiency is rare – leads to scaly skin rash, dermatitis, poor growth, lower immune system
Characteristics of Omega 9
Nonessential – body can synthesize

13. #5 Functions of Fatty Acids
Omega 6 Fats
Too much (eicosanoids) may promote inflammation, constrict blood vessels and cause clotting.
18:6 Fat sources
Nuts, seeds and corn oil

14. #5 Functions of Fatty Acids
Omega 3 Fats
Improves inflammatory conditions: arthritis, psoriasis, asthma and skin conditions
Improves ulcerativie colitis and Chron’s disease
Lowers Triglycerides and Raises HDL, reduces clotting, lowers blood pressure
Reduces insulin resistance, lowers Diabetes risk
Preserves renal function and reduces vascular access thromobosis in dialysis patients.
Reduces severity of Alzheimers, deperssion, and bipolar
Improves growth and development of brain

15. Omega 3 sources Omega 3 sources Fatty fish
Canola, soybean, walnut and flaxseed oil

16. #8 Fats in our foods Saturated Fat pg 190
Butter Coconut oil
Lard
Beef Tallow

17. #8 Fats in our Foods Monounsaturated Fats
Olive oil
Peanut oil
Safflower

18. #8 Fats in Our Foods Polyunsaturated fats pg 190
Sunflower oil
Corn oil
Soybean oil
Cotton seed oil

19. Top Foods with Trans Fats
1. Spreads. Margarine
Stick margarine has 2.8 grams of trans fat per tablespoon, and 2.1 grams of saturated fat.
Tub margarine has 0.6 grams of trans fat per tablespoon, and 1.2 grams of saturated fat.
Shortening has 4.2 grams of trans fat per tablespoon, and 3.4 grams of saturated fat.
2. Processed foods: shelf stable cookies, donuts, cornbread mixes, pancake mixes, crackers and chips
3. Non dairy creamers, whipped topping, gravy mixes, salad dressings

20. Video Facts about Fats

21. #12, 13 Phospholipids Structure Functions Food sources
Glycerol + 2 fatty acids + phosphate group
Functions
Component of cell membranes
Lipid transport as part of lipoproteins
Emulsifiers
Food sources
Egg yolks, liver, soybeans, peanuts

22. #14, 21 Transport Lipids in the Body
Lipoproteins carry lipids around the body
Chylomicrons
Delivers dietary lipids from intestines to cells and liver

23. #14, 21 Transport Lipids in the Body
Very low density lipoproteins (VLDLs)
Deliver triglycerides to cells
Intermediate-density lipoproteins
Remove some phospholipids
Low-density lipoproteins (LDLs)
Deliver cholesterol to cells
High-density lipoproteins (HDLs)
Pick up cholesterol for removal or recycling

24. #15-17 Sterols: Cholesterol
Structure - multi ring Functions
Component of cell membranes
Precursor to other substances
Sterol hormones
Vitamin D
Bile acids
Synthesis
Made in the liver-1000mg/day
Food sources
Found only in animal foods
Cholesterol and Vitamin D occur in foods

25. Cholesterol in the diet
mg per large egg yolk
324 mg in 3 oz beef liver
24 mg in whole milk, 5mg in skim milk
31 mg in 1 TBSP butter
73 mg per 3 oz lean pork
76 mg per 3 oz ground beef
Breastmilk is high in cholesterol for brain development
Daily recommendation is <300mg/day

26. #18-20 Lipid Digestion and Absorption
Mouth and stomach
Minimal digestion of triglycerides
Small intestine
Emulsified by phospholipids
Digested by pancreatic lipase
Absorbed into intestinal cells
Formed into chylomicrons and moved into lymphatic system

27. #19 Lipid Digestion/Absorption
CCK – hormone cholecystokinin Is released from small intestine
Bile – CCK signals gallbladder to contract to release BILE into duodenum and emulsifies fats
Lipase – Pancreatic lipase digests TG
Know how many grams of fat you need a day to make the gallbladder contract? 10 grams a day

28. #21 Lipid Digestion and Absorption
Digestibility
Steatorrhea – fatty, frothy stools indicate fat malabsorption, pancreatic issues
<7grams of fat should be in stools in a 24 hour time frame
Most fat absorption takes place in Duodenum or jejunum in Small intestine
Cholesterol carried out with soluble fiber

29. #22 Negative Health Effects of Lipids
Obesity
High-fat diets promote weight gain
Heart disease
High saturated and trans fat intake raises LDL cholesterol
Cancer

30. #22 Positive Health Effects of Lipids
Omega 3 Fats:
Reduce inflammation
Reduce heart disease risk
To increase Omega 3 :
1.5-2 tsp canola or soybean oil each day
4 meals containing fatty fish each week.
Mackerel, tuna, salmon, trout, herring or cod liver oil

31. #23 Fat Recommendations in the Diet
Recommended intake
Consume at least two weekly servings of oily fish
Balance of calories from fat and carbohydrate
Reduce sat and trans fat intake
Total fat: 20–35 percent of calories
Need ~2 percent of calories as essential fatty acids
Improve balance of omega-3: omega-6 fatty acids

32. AHA Position on Omega-3 Fatty Acids
The American Heart Association recommends eating fish (particularly fatty fish) at least two times a week. Fish is a good source of protein and doesn’t have high saturated fat that fatty meat products do.
Fatty fish such as mackerel, lake trout, herring, sardines, albacore tuna, and salmon are high in two kinds of omega-3 fatty acids: eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

33. Lipids in the Diet Fat substitutes
The Olestra Controversy: Are Fat Replacers Safe? composition
Sucrose + fatty acids
Indigestible – provides zero kcals and causes diarrhea
Reduces absorption of fat-soluble vitamins

34. A Healthy Balance
An appropriate balance of calories from fat and carbohydrates can have multiple health benefits aside from controlling weight.
These include cholesterol levels, vitamin intake, etc.

35. Recommended Fat Intake
The Dietary Guidelines for Americans recommends a fat intake of 20 to 35 percent of total calories.
Saturated fat should supply no more than 10 percent of our total calories, or about one-third of our fat calories.

36. NCEP Tips for Healthful Eating Out
Choose restaurants that have low-fat, low-cholesterol menu items.
Don’t be afraid to ask for foods that follow your eating pattern.
Select poultry, fish, or meat that is broiled, grilled, baked, steamed, or poached rather than fried.

37. Adult Cholesterol Level Recommendations
Total Cholesterol : <200 mg/dL
>240 mg/dL is High blood cholesterol. A person with this level has more than twice the risk of coronary heart disease as someone whose cholesterol is below 200 mg/dL.
Soluble fiber, exercise, and heart healthy diet improve total cholesterol

38. Adult Cholesterol Level:
HDL – High Density Lipoprotein
The GOOD cholesterol
>60 mg/dL
Improve levels by exercise, heart healthy diet, fatty fish, and
Lethicin supplement (1200mg 3 x day)
Lethicin converts LDL to HDL

39. Adult Cholesterol Level:
LDL : BAD
<100mg/dL
Improve levels by exercise, low saturated/trans fat diet, lethicin supplement

40. Adult Cholesterol Levels
Triglycerides
<150 mg/dL
Avoiding high sugar foods, pastries, sodas, alcohol,
Control weight