Understanding Nutrition 14th Edition by Eleanor Noss Whitney- Sharon Rady Rolfes - Test Bank

Understanding Nutrition 14th Edition by Eleanor Noss Whitney- Sharon Rady Rolfes – Test Bank

 

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Sample Questions Are Posted Below

 

Chapter 5 – The Lipids: Triglycerides, Phospholipids, and Sterols

 

MULTIPLE CHOICE

 

1. In which form are most dietary lipids found?

a.	Sterols
b.	Glycerols
c.	Triglycerides
d.	Monoglycerides
e.	Polyglycerides

 

 

ANS:  C                    DIF:    Bloom’s: Remember

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

2. Lipids that are solid at room temperature are known as ____.

a.	oils
b.	fats
c.	omegas
d.	glycerols
e.	phospholipids

 

 

ANS:  B                    DIF:    Bloom’s: Remember

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

3. Lipids that are liquid at room temperature are known as ____.

a.	oils
b.	fats
c.	omegas
d.	glycerols
e.	phospholipids

 

 

ANS:  A                    DIF:    Bloom’s: Remember

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

4. What is the chemical composition of fats?

a.	Hexose polymers
b.	Glycogen granules
c.	Fatty acids and glycerol
d.	Combinations of long-chain fatty acids
e.	Esters of carbon and hydrogen

 

 

ANS:  C                    DIF:    Bloom’s: Remember

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

5. Which item is a chief source of short-chain and medium-chain fatty acids?

a.	Fish
b.	Eggs
c.	Dairy
d.	Soybeans
e.	Fruit

 

 

ANS:  C                    DIF:    Bloom’s: Remember

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

6. Lipids differ in their degree of saturation or unsaturation due to their number of ____.

a.	amino acids
b.	double bonds
c.	saccharide units
d.	peptide linkages
e.	oxygen atoms

 

 

ANS:  B                    DIF:    Bloom’s: Understand

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

7. What is a common dietary saturated fatty acid?

a.	Oleic acid
b.	Stearic acid
c.	Linolenic acid
d.	Arachidonic acid
e.	Lineolic acid

 

 

ANS:  B                    DIF:    Bloom’s: Remember

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

8. Which compound is missing four or more hydrogen atoms?

a.	Monounsaturated fatty acid
b.	Polyunsaturated fatty acid
c.	Long-chain saturated fatty acid
d.	Short-chain saturated fatty acid
e.	Triglycerides

 

 

ANS:  B                    DIF:    Bloom’s: Remember

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

9. The easiest way to increase intake of oleic acid is to consume more ____.

a.	lard oil
b.	corn oil
c.	olive oil
d.	safflower oil
e.	tallow oil

 

 

ANS:  C                    DIF:    Bloom’s: Understand

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

10. What product has the highest percentage of its fat in saturated form?

a.	Butter
b.	Walnut oil
c.	Beef tallow
d.	Coconut oil
e.	Chicken fat

 

 

ANS:  D                    DIF:    Bloom’s: Understand

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

11. Which product has the highest percentage of its fat in polyunsaturated form?

a.	Butter
b.	Corn oil
c.	Beef tallow
d.	Coconut oil
e.	Palm oil

 

 

ANS:  B                    DIF:    Bloom’s: Remember

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

12. Which product provides abundant amounts of omega-3 fatty acids?

a.	Palm oil
b.	Walnut oil
c.	Soybean oil
d.	Flaxseed oil
e.	Corn oil

 

 

ANS:  D                    DIF:    Bloom’s: Remember

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

13. Which product is considered a major source of polyunsaturated fat?

a.	Corn oil
b.	Palm oil
c.	Peanut oil
d.	Chicken fat
e.	Olive oil

 

 

ANS:  A                    DIF:    Bloom’s: Remember

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

14. What is a conjugated linoleic acid?

a.	A type of cis-fatty acid
b.	A partially hydrogenated omega-6 lipid
c.	A fatty acid with the chemical make-up of linoleic acid but with a different configuration
d.	A fatty acid resulting from the partial hydrolysis of dietary phospholipids in the intestinal tract
e.	A nitrogen-containing compound found in foods and made in the body from the amino acid methionine.

 

 

ANS:  C                    DIF:    Bloom’s: Understand

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

15. Which statement describes a feature of trans-fatty acids?

a.	In nature, most double bonds are trans.
b.	Hydrogenation converts trans-fatty acids to cis-fatty acids.
c.	The conversion of cis-fatty acids to trans-fatty acids is inhibited by the presence of antioxidants.
d.	In the body, trans-fatty acids are metabolized more like saturated fats than like unsaturated fats.
e.	The hydrogen atoms are located on the same side of a double bond.

 

 

ANS:  D                    DIF:    Bloom’s: Understand

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

16. What type of compound is lecithin?

a.	Bile salt
b.	Glycolipid
c.	Lipoprotein
d.	Phospholipid
e.	Sterol

 

 

ANS:  D                    DIF:    Bloom’s: Remember

REF:   5.2 The Chemist’s View of Phospholipids and Sterols

OBJ: UNUT.WHRO.16.5.2 Describe the chemistry, food sources, and roles of phospholipids and sterols.

 

17. Which statement describes is a feature of choline?

a.	It is a part of lecithin.
b.	It is a type of cis-fatty acid.
c.	It is a type of trans-fatty acid.
d.	It is attached to omega-3 fatty acids.
e.	It has a multiple ring structure.

 

 

ANS:  A                    DIF:    Bloom’s: Remember

REF:   5.2 The Chemist’s View of Phospholipids and Sterols

OBJ: UNUT.WHRO.16.5.2 Describe the chemistry, food sources, and roles of phospholipids and sterols.

 

18. About how much cholesterol is synthesized by the liver every day?

a.	100 to 300 mg
b.	300 to 500 mg
c.	500 to 800 mg
d.	800 to 1500 mg
e.	1500 to 2500 mg

 

 

ANS:  D                    DIF:    Bloom’s: Remember

REF:   5.2 The Chemist’s View of Phospholipids and Sterols

OBJ: UNUT.WHRO.16.5.2 Describe the chemistry, food sources, and roles of phospholipids and sterols.

 

19. Which food contains cholesterol?

a.	Corn
b.	Olives
c.	Roasted turkey
d.	Roasted peanuts
e.	Boiled potatoes

 

 

ANS:  C                    DIF:    Bloom’s: Remember

REF:   5.2 The Chemist’s View of Phospholipids and Sterols

OBJ: UNUT.WHRO.16.5.2 Describe the chemistry, food sources, and roles of phospholipids and sterols.

 

20. What is the major source of “good” cholesterol?

a.	Fatty fish
b.	Fatty meat
c.	Endogenous synthesis
d.	Monounsaturated and polyunsaturated fatty acids
e.	Dairy foods

 

 

ANS:  C                    DIF:    Bloom’s: Remember

REF:   5.2 The Chemist’s View of Phospholipids and Sterols

OBJ: UNUT.WHRO.16.5.2 Describe the chemistry, food sources, and roles of phospholipids and sterols.

 

21. Which of the following is a characteristic of cholesterol?

a.	It is absorbed directly into the blood
b.	It is a precursor for bile and vitamin D synthesis
c.	It is not formed in the body when provided by the diet
d.	It is found in abundance in tropical fats such as palm oil
e.	It has no functions in the healthy body.

 

 

ANS:  B                    DIF:    Bloom’s: Understand

REF:   5.2 The Chemist’s View of Phospholipids and Sterols

OBJ: UNUT.WHRO.16.5.2 Describe the chemistry, food sources, and roles of phospholipids and sterols.

 

22. What term may be used to describe a hydrophobic substance?

a.	Lipophilic
b.	Lipophobic
c.	Glycerophilic
d.	Glycerophobic
e.	Emulsifiable

 

 

ANS:  A                    DIF:    Bloom’s: Remember

REF:   5.2 The Chemist’s View of Phospholipids and Sterols

OBJ: UNUT.WHRO.16.5.2 Describe the chemistry, food sources, and roles of phospholipids and sterols.

 

23. Which statement characterizes the lipase enzymes?

a.	Gastric lipase plays a significant role in fat digestion in adults
b.	Intestinal mucosal lipase is responsible for most dietary fat digestion
c.	Salivary gland lipase (lingual lipase) plays an active role in fat digestion in infants
d.	Pancreatic lipase hydrolyzes most dietary triglycerides completely to glycerol and free fatty acids
e.	Pancreatic lipase forms emulsified fats from monoglycerides

 

 

ANS:  C                    DIF:    Bloom’s: Understand

REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

24. In the digestion of fats, emulsifiers function as ____.

a.	enzymes
b.	hormones
c.	detergents
d.	chylomicrons
e.	macrophages

 

 

ANS:  C                    DIF:    Bloom’s: Remember

REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

25. What part of the gastrointestinal tract is the predominant site of dietary fat hydrolysis?

a.	Mouth
b.	Stomach
c.	Small intestine
d.	Large intestine
e.	Esophagus

 

 

ANS:  C                    DIF:    Bloom’s: Remember

REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

26. Chylomicrons are synthesized within the ____.

a.	liver
b.	intestinal cells
c.	lymphatic system
d.	storage compartment of plant seeds
e.	spleen

 

 

ANS:  B                    DIF:    Bloom’s: Remember

REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

27. How is soluble fiber in the diet thought to help lower blood cholesterol level?

a.	It denatures cholesterol in the stomach.
b.	It hydrolyzes cholesterol in the intestinal tract.
c.	It traps cholesterol in the intestinal tract and thus inhibits its absorption.
d.	It enhances excretion of bile leading to increased cholesterol turnover.
e.	It binds to the fats and denatures them.

 

 

ANS:  D                    DIF:    Bloom’s: Understand

REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

 

28. Bile is known to assist in the absorption of ____.

a.	fat
b.	carbohydrate
c.	protein
d.	vitamins
e.	minerals

 

 

ANS:  A                    DIF:    Bloom’s: Remember

REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

29. Spherical complexes of emulsified fats are known as ____.

a.	micelles
b.	chylomicrons
c.	monolipomicrons
d.	endogenous bilayer aggregates
e.	polymerized lipids

 

 

ANS:  A                    DIF:    Bloom’s: Remember

REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

30. Which example characterizes enterohepatic circulation?

a.	Chylomicron conversion to LDLs and HDLs
b.	Recycling of bile from the intestine to the liver
c.	Hormonal control of pancreatic digestive secretions
d.	Liver secretion of eicosanoids that promote absorption of eicosanoid precursors
e.	Cholesterol that is made from bile in the small intestine and transported to the liver

 

 

ANS:  B                    DIF:    Bloom’s: Understand

REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

31. In comparison to a low-density lipoprotein, a high-density lipoprotein contains ____.

a.	less lipid
b.	less protein
c.	more cholesterol
d.	more carbohydrate
e.	more triglyceride

 

 

ANS:  A                    DIF:    Bloom’s: Understand

REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

32. Which lipoprotein contains the highest percentage of cholesterol?

a.	Chylomicron
b.	Low-density lipoprotein
c.	High-density lipoprotein
d.	Very-low-density lipoprotein
e.	Very-high density lipoprotein

 

 

ANS:  B                    DIF:    Bloom’s: Remember

REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

33. After a fat-containing meal is absorbed, about how many hours does it take the body to remove the chylomicrons from the blood?

a.	2
b.	5
c.	10
d.	14
e.	16

 

 

ANS:  D                    DIF:    Bloom’s: Remember

REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

34. What tissue contains special receptors for removing low-density lipoproteins from the circulation?

a.	Liver
b.	Adipose
c.	Arterial walls
d.	Skeletal muscle
e.	Smooth muscle

 

 

ANS:  A                    DIF:    Bloom’s: Remember

REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

35. A high risk of heart attack correlates with high blood levels of ____.

a.	free fatty acids
b.	high-density lipoproteins
c.	low-density lipoproteins
d.	very low-density lipoproteins
e.	omega-3 fatty acids

 

 

ANS:  C                    DIF:    Bloom’s: Remember

REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

36. What are the substances resistin and adiponectin?

a.	Glycolipids that regulate synthesis of lipoproteins
b.	Intestinal cell hormones that regulate secretion of bile
c.	Intestinal cell hormones that trigger secretion of pancreatic juice
d.	Proteins secreted from fat cells that help regulate energy balance
e.	Substances that dampen inflammation and decrease insulin resistance

 

 

ANS:  D                    DIF:    Bloom’s: Remember                        REF:   5.4 Lipids in the Body

OBJ: UNUT.WHRO.16.5.4 Outline the major roles of fats in the body, including a discussion of essential fatty acids and the omega fatty acids.

 

37. An important function of fat in the body is to ____.

a.	build muscle tissue
b.	regulate blood glucose levels
c.	protect vital organs against shock
d.	provide precursors for glucose synthesis
e.	facilitate reproduction

 

 

ANS:  C                    DIF:    Bloom’s: Understand                       REF:   5.4 Lipids in the Body

OBJ: UNUT.WHRO.16.5.4 Outline the major roles of fats in the body, including a discussion of essential fatty acids and the omega fatty acids.

 

38. Which lipid is an essential nutrient?

a.	Lecithin
b.	Cholesterol
c.	Stearic acid
d.	Linoleic acid
e.	Adipokine

 

 

ANS:  D                    DIF:    Bloom’s: Remember                        REF:   5.4 Lipids in the Body

OBJ: UNUT.WHRO.16.5.4 Outline the major roles of fats in the body, including a discussion of essential fatty acids and the omega fatty acids.

 

39. Which acid is an omega-3 fat?

a.	Acetic acid
b.	Palmitic acid
c.	Linoleic acid
d.	Docosahexaenoic acid
e.	Arachidonic acid

 

 

ANS:  D                    DIF:    Bloom’s: Remember                        REF:   5.4 Lipids in the Body

OBJ: UNUT.WHRO.16.5.4 Outline the major roles of fats in the body, including a discussion of essential fatty acids and the omega fatty acids.

 

40. What is the immediate precursor for the eicosanoids?

a.	Glucose
b.	Hormones
c.	Fatty acids
d.	Cholesterol
e.	Lipases

 

 

ANS:  C                    DIF:    Bloom’s: Remember                        REF:   5.4 Lipids in the Body

OBJ: UNUT.WHRO.16.5.4 Outline the major roles of fats in the body, including a discussion of essential fatty acids and the omega fatty acids.

 

41. Aspirin works to reduce the symptoms of infection or pain by retarding the synthesis of

a.	arachidonic acid.
b.	certain eicosanoids.
c.	certain saturated fatty acids.
d.	certain unsaturated fatty acids.
e.	certain adipokines

 

 

ANS:  B                    DIF:    Bloom’s: Understand                       REF:   5.4 Lipids in the Body

OBJ: UNUT.WHRO.16.5.4 Outline the major roles of fats in the body, including a discussion of essential fatty acids and the omega fatty acids.

 

42. What are the precursors for synthesis of the eicosanoids?

a.	Steroids
b.	Short-chain fatty acids
c.	Medium-chain saturated fatty acids
d.	Long-chain polyunsaturated fatty acids
e.	Monounsaturated fatty acids

 

 

ANS:  D                    DIF:    Bloom’s: Remember                        REF:   5.4 Lipids in the Body

OBJ: UNUT.WHRO.16.5.4 Outline the major roles of fats in the body, including a discussion of essential fatty acids and the omega fatty acids.

 

43. What is the function of lipoprotein lipase?

a.	Synthesizes lipoproteins in liver cells
b.	Synthesizes triglycerides in adipose cells
c.	Assembles lipid particles into chylomicrons
d.	Hydrolyzes blood triglycerides for uptake into cells
e.	Stimulates the release of triglycerides from the liver

 

 

ANS:  D                    DIF:    Bloom’s: Remember                        REF:   5.4 Lipids in the Body

OBJ: UNUT.WHRO.16.5.4 Outline the major roles of fats in the body, including a discussion of essential fatty acids and the omega fatty acids.

 

44. What is the function of adipose cell hormone-sensitive lipase?

a.	Hydrolyzes hormones involved in fat breakdown
b.	Synthesizes new adipose cells from simple fatty acids
c.	Hydrolyzes triglycerides to provide fatty acids for other cells
d.	Synthesizes long-chain fatty acids to provide precursors for other cells
e.	Regulation of blood pressure and blood clotting

 

 

ANS:  C                    DIF:    Bloom’s: Remember                        REF:   5.4 Lipids in the Body

OBJ: UNUT.WHRO.16.5.4 Outline the major roles of fats in the body, including a discussion of essential fatty acids and the omega fatty acids.

 

45. Approximately what percentage of the body’s energy needs at rest is supplied by fat?

a.	5
b.	25
c.	40
d.	60
e.	75

 

 

ANS:  D                    DIF:    Bloom’s: Remember                        REF:   5.4 Lipids in the Body

OBJ: UNUT.WHRO.16.5.4 Outline the major roles of fats in the body, including a discussion of essential fatty acids and the omega fatty acids.

 

46. How much energy does one gram of fat provide?

a.	3 kcal
b.	5 kcal
c.	7 kcal
d.	9 kcal
e.	11 kcal

 

 

ANS:  D                    DIF:    Bloom’s: Remember                        REF:   5.4 Lipids in the Body

OBJ: UNUT.WHRO.16.5.4 Outline the major roles of fats in the body, including a discussion of essential fatty acids and the omega fatty acids.

 

47. The results of blood tests that reveal a person’s total cholesterol and triglycerides are called a ____.

a.	lipid profile
b.	circulating fat count
c.	personal lipids count
d.	degenerative disease assessment
e.	lipid balance ratio

 

 

ANS:  A                    DIF:    Bloom’s: Remember

REF:   5.5 Health Effects and Recommended Intakes of Saturated Fats, Trans Fats, and Cholesterol

OBJ: UNUT.WHRO.16.5.5 Explain the relationships among saturated fat, trans fat, and cholesterol and chronic diseases, noting recommendations.

 

48. Which source of lipids should be substituted for saturated fats to help lower blood cholesterol levels?

a.	Butter
b.	Canola oil
c.	Coconut oil
d.	Stick margarine
e.	Shortening

 

 

ANS:  B                    DIF:    Bloom’s: Understand

REF:   5.5 Health Effects and Recommended Intakes of Saturated Fats, Trans Fats, and Cholesterol

OBJ: UNUT.WHRO.16.5.6 Explain the relationships between monounsaturated and polyunsaturated fats and health, noting recommendations.

 

49. Which statement best describes the nutritional value of eggs?

a.	Eggs are high in both cholesterol and saturated fat.
b.	High omega-3 fat eggs are now available by prescription only.
c.	Although it is high in cholesterol, the egg is low in saturated fat.
d.	Even in people with a healthy lipid profile, consumption of one egg/day is detrimental.
e.	Egg substitutes often have higher levels of cholesterol than do eggs.

 

 

ANS:  C                    DIF:    Bloom’s: Understand

REF:   5.5 Health Effects and Recommended Intakes of Saturated Fats, Trans Fats, and Cholesterol

OBJ: UNUT.WHRO.16.5.6 Explain the relationships between monounsaturated and polyunsaturated fats and health, noting recommendations.

 

50. Which statement is true of the relationship fat intake and health?

a.	Intake of saturated fat raises blood cholesterol more than intake of cholesterol
b.	High intakes of fish oil lower bleeding time and improve diabetes and wound healing
c.	High intakes of short- and medium-chain fatty acids raise high-density lipoprotein levels
d.	Trans-fatty acids contained in polyunsaturated fats but not in monounsaturated fats alter blood cholesterol levels
e.	Trans-fatty acids are not as dangerous as once believed

 

 

ANS:  A                    DIF:    Bloom’s: Understand

REF:   5.5 Health Effects and Recommended Intakes of Saturated Fats, Trans Fats, and Cholesterol

OBJ: UNUT.WHRO.16.5.5 Explain the relationships among saturated fat, trans fat, and cholesterol and chronic diseases, noting recommendations.

 

51. What is the approximate average daily trans-fatty acid intake in the United States?

a.	500 mg
b.	2 g
c.	5 g
d.	12 g
e.	18 g

 

 

ANS:  C                    DIF:    Bloom’s: Remember

REF:   5.5 Health Effects and Recommended Intakes of Saturated Fats, Trans Fats, and Cholesterol

OBJ: UNUT.WHRO.16.5.5 Explain the relationships among saturated fat, trans fat, and cholesterol and chronic diseases, noting recommendations.

 

52. When consumed regularly, which fatty acid helps prevent the formation of blood clots?

a.	Oleic acid
b.	Stearic acid
c.	Arachidonic acid
d.	Eicosapentaenoic acid
e.	Linoleic acid

 

 

ANS:  D                    DIF:    Bloom’s: Remember

REF:   5.6 Health Effects and Recommended Intakes of Monounsaturated and Polyunsaturated Fats

OBJ: UNUT.WHRO.16.5.6 Explain the relationships between monounsaturated and polyunsaturated fats and health, noting recommendations.

 

53. Approximately how much saturated fat is in 8 ounces of whole milk?

a.	2 g
b.	5 g
c.	8 g
d.	12 g
e.	15 g

 

 

ANS:  B                    DIF:    Bloom’s: Remember

REF:   5.6 Health Effects and Recommended Intakes of Monounsaturated and Polyunsaturated Fats

OBJ: UNUT.WHRO.16.5.6 Explain the relationships between monounsaturated and polyunsaturated fats and health, noting recommendations.

 

54. Approximately how much saturated fat is in a plain baked potato?

a.	0 g
b.	1 g
c.	2 g
d.	3 g
e.	4 g

 

 

ANS:  A                    DIF:    Bloom’s: Remember

REF:   5.6 Health Effects and Recommended Intakes of Monounsaturated and Polyunsaturated Fats

OBJ: UNUT.WHRO.16.5.6 Explain the relationships between monounsaturated and polyunsaturated fats and health, noting recommendations.

 

55. A lacto-ovo vegetarian wishing to ensure a liberal intake of linolenic acid should consume ____.

a.	eggs and milk	c.	safflower oil margarine
b.	canola oil and walnuts	d.	corn oil and sunflower oil

 

 

ANS:  B                    DIF:    Bloom’s: Understand

REF:   5.6 Health Effects and Recommended Intakes of Monounsaturated and Polyunsaturated Fats

OBJ: UNUT.WHRO.16.5.6 Explain the relationships between monounsaturated and polyunsaturated fats and health, noting recommendations.

 

56. A person who regularly consumes fish such as shark, king mackerel, and swordfish is at risk for ingesting potentially toxic amounts of ____.

a.	EPA
b.	DHA
c.	mercury
d.	cadmium
e.	dioxins

 

 

ANS:  C                    DIF:    Bloom’s: Remember

REF:   5.6 Health Effects and Recommended Intakes of Monounsaturated and Polyunsaturated Fats

OBJ: UNUT.WHRO.16.5.6 Explain the relationships between monounsaturated and polyunsaturated fats and health, noting recommendations.

 

57. Which product is a good source of eicosapentaenoic acid?

a.	Tuna
b.	Butter
c.	Salad oil
d.	Shortening
e.	Corn oil

 

 

ANS:  A                    DIF:    Bloom’s: Understand

REF:   5.6 Health Effects and Recommended Intakes of Monounsaturated and Polyunsaturated Fats

OBJ: UNUT.WHRO.16.5.6 Explain the relationships between monounsaturated and polyunsaturated fats and health, noting recommendations.

 

58. The oils found in walnuts, soybeans, flaxseed, and wheat germ represent a good source of preformed ____.

a.	eicosanoids
b.	linolenic acid
c.	docosahexaenoic acid
d.	eicosapentaenoic acid
e.	linoleic acid

 

 

ANS:  B                    DIF:    Bloom’s: Understand

REF:   5.6 Health Effects and Recommended Intakes of Monounsaturated and Polyunsaturated Fats

OBJ: UNUT.WHRO.16.5.6 Explain the relationships between monounsaturated and polyunsaturated fats and health, noting recommendations.

 

59. Which statement describes a recognized relationship between dietary fat and cancer?

a.	Fat from milk does not increase risk for cancer.
b.	Dietary fat initiates rather than promotes cancer formation.
c.	High intakes of omega-3 fatty acids promote cancer development in animals.
d.	The evidence linking fat intake with cancer is stronger than that linking it with heart disease.
e.	There is a strong link between breast cancer incidence and dietary fat.

 

 

ANS:  A                    DIF:    Bloom’s: Understand

REF:   5.5 Health Effects and Recommended Intakes of Saturated Fats, Trans Fats, and Cholesterol

OBJ: UNUT.WHRO.16.5.5 Explain the relationships among saturated fat, trans fat, and cholesterol and chronic diseases, noting recommendations.

 

60. According to the Dietary Guidelines, what should be the maximum total fat intake as a percentage of energy intake?

a.	10
b.	20
c.	35
d.	50
e.	60

 

 

ANS:  C                    DIF:    Bloom’s: Remember

REF:   5.5 Health Effects and Recommended Intakes of Saturated Fats, Trans Fats, and Cholesterol

OBJ: UNUT.WHRO.16.5.5 Explain the relationships among saturated fat, trans fat, and cholesterol and chronic diseases, noting recommendations.

 

61. For most adults, what is the recommended minimum amount of fat that should be consumed, as a percentage of total energy intake?

a.	5
b.	15
c.	20
d.	35
e.	45

 

 

ANS:  C                    DIF:    Bloom’s: Remember

REF:   5.5 Health Effects and Recommended Intakes of Saturated Fats, Trans Fats, and Cholesterol

OBJ: UNUT.WHRO.16.5.5 Explain the relationships among saturated fat, trans fat, and cholesterol and chronic diseases, noting recommendations.

 

62. What is the recommended range of daily fat consumption for an individual on a 2000 calorie diet?

a.	5 to 15 grams
b.	20 to 35 grams
c.	45 to 75 grams
d.	80 to 100 grams
e.	125 to 150 grams

 

 

ANS:  C                    DIF:    Bloom’s: Remember

REF:   5.5 Health Effects and Recommended Intakes of Saturated Fats, Trans Fats, and Cholesterol

OBJ: UNUT.WHRO.16.5.5 Explain the relationships among saturated fat, trans fat, and cholesterol and chronic diseases, noting recommendations.

 

63. Surveys show that U.S. adults’ average intake of fat as a percentage of total energy intake is ____.

a.	14%
b.	24%
c.	34%
d.	44%
e.	54%

 

 

ANS:  C                    DIF:    Bloom’s: Remember

REF:   5.5 Health Effects and Recommended Intakes of Saturated Fats, Trans Fats, and Cholesterol

OBJ: UNUT.WHRO.16.5.5 Explain the relationships among saturated fat, trans fat, and cholesterol and chronic diseases, noting recommendations.

 

64. The average daily cholesterol intake of U.S. women is about ____.

a.	134 mg
b.	184 mg
c.	224 mg
d.	274 mg
e.	304 mg

 

 

ANS:  C                    DIF:    Bloom’s: Remember

REF:   5.5 Health Effects and Recommended Intakes of Saturated Fats, Trans Fats, and Cholesterol

OBJ: UNUT.WHRO.16.5.5 Explain the relationships among saturated fat, trans fat, and cholesterol and chronic diseases, noting recommendations.

 

65. Which statement is true of fat in the diet of athletes?

a.	A minimum of 20% fat energy in the diet is needed.
b.	Energy derived from fat has very little bearing on performance.
c.	Optimal performance is found with a high-carbohydrate, 15% total fat kcalories diet.
d.	Diets with at least 10% total kcalories from fat are still able to provide the recommended amounts of micronutrients.
e.	It is especially important for female athletes to keep their fat intake to less than 15% of their total kcal.

 

 

ANS:  A                    DIF:    Bloom’s: Understand

REF:   5.5 Health Effects and Recommended Intakes of Saturated Fats, Trans Fats, and Cholesterol

OBJ: UNUT.WHRO.16.5.5 Explain the relationships among saturated fat, trans fat, and cholesterol and chronic diseases, noting recommendations.

 

66. Which statement describes the lipid content of livestock?

a.	The meat from grass-fed animals is similar in composition to soy protein.
b.	Grass-fed animals contain more omega-3 fats in the meat than grain-fed animals.
c.	Grain-fed animals contain more polyunsaturated fatty acids in the meat compared with grass-fed animals.
d.	Grain-fed animals contain lower concentrations of fat in the meat compared with grass-fed animals.
e.	There are no significant differences between the fat composition of grass and grain fed cattle.

 

 

ANS:  B                    DIF:    Bloom’s: Understand

REF:   5.6 Health Effects and Recommended Intakes of Monounsaturated and Polyunsaturated Fats

OBJ: UNUT.WHRO.16.5.6 Explain the relationships between monounsaturated and polyunsaturated fats and health, noting recommendations.

 

67. What dietary advice is appropriate for reducing fat intake?

a.	Limit intake of all fried foods because they contain abundant fat.
b.	Substitute crackers and cornbread for other starches because they are likely lower in fat.
c.	Consume foods with more invisible fat because this type of fat is not absorbed well from the digestive tract.
d.	Increase consumption of soups, such as cream-of-mushroom soup prepared with water, because the fat content is usually very low.
e.	Increase dairy consumption while decreasing consumption of fats from other sources, because dairy fats do not contribute to disease.

 

 

ANS:  A                    DIF:    Bloom’s: Understand

REF:   5.6 Health Effects and Recommended Intakes of Monounsaturated and Polyunsaturated Fats

OBJ: UNUT.WHRO.16.5.6 Explain the relationships between monounsaturated and polyunsaturated fats and health, noting recommendations.

 

68. Which statement describes a drawback of olestra consumption?

a.	It yields 9 kcalories per gram.
b.	It imparts off-flavors to foods.
c.	It raises blood glucose levels.
d.	It inhibits absorption of vitamin E.
e.	It can cause severe constipation.

 

 

ANS:  D                    DIF:    Bloom’s: Understand

REF:   5.6 Health Effects and Recommended Intakes of Monounsaturated and Polyunsaturated Fats

OBJ: UNUT.WHRO.16.5.6 Explain the relationships between monounsaturated and polyunsaturated fats and health, noting recommendations.

 

69. Of the total fat content of the most commonly eaten nuts in the United States, what is the approximate percentage of monounsaturated fat?

a.	29
b.	39
c.	49
d.	59
e.	69

 

 

ANS:  D                    DIF:    Bloom’s: Remember

REF:   H-5 High-Fat Foods—Friend or Foe?

OBJ: UNUT.WHRO.16.H-5 Identify which fats support health and which impair it.

 

70. A major feature of the Mediterranean diet is liberal intake of ____.

a.	eggs
b.	olive oil
c.	lean meat
d.	fortified butter
e.	cheese

 

 

ANS:  B                    DIF:    Bloom’s: Understand

REF:   H-5 High-Fat Foods—Friend or Foe?

OBJ: UNUT.WHRO.16.H-5 Identify which fats support health and which impair it.

 

COMPLETION

 

1. All ____________________ have the same basic structure—a chain of carbon and hydrogen atoms with an acid group (COOH) at one end and a methyl group (CH3) at the other end.

 

ANS:  fatty acids

 

DIF:    Bloom’s: Remember

REF:   The Chemist’s View of Fatty acids and Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

2. Triglycerides are composed of three fatty acids attached to a(n) ____________________.

 

ANS:  glycerol

 

DIF:    Bloom’s: Remember

REF:   The Chemist’s View of Fatty acids and Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

3. During ____________________, some or all of the points of unsaturation are saturated by adding hydrogen molecules.  .

 

ANS:  hydrogenation

 

DIF:    Bloom’s: Remember

REF:   The Chemist’s View of Fatty acids and Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

4. The best-known phospholipid is ____________________.

 

ANS:  lecithin

 

DIF:    Bloom’s: Remember                        REF:   5.2 The Chemist’s View of Phospholipids and Sterols

OBJ: UNUT.WHRO.16.5.2 Describe the chemistry, food sources, and roles of phospholipids and sterols.

 

5. Cholesterol from outside the body is called ____________________ cholesterol.

 

ANS:  exogenous

 

DIF:    Bloom’s: Remember                        REF:   5.2 The Chemist’s View of Phospholipids and Sterols

OBJ: UNUT.WHRO.16.5.2 Describe the chemistry, food sources, and roles of phospholipids and sterols.

 

6. Monoglycerides and long-chain fatty acids are emulsified by bile, forming spherical complexes known as ____________________.

 

ANS:  micelles

 

DIF:    Bloom’s: Remember                        REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

7. The ____________________ are the largest and least dense of the lipoproteins.

 

ANS:  chylomicrons

 

DIF:    Bloom’s: Remember                        REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

8. Adipose tissue actively secretes several hormones known as ____________________—proteins that help regulate energy balance and influence several body functions.

 

ANS:  adipokines

 

DIF:    Bloom’s: Remember                        REF:   5.4 Lipids in the Body

OBJ: UNUT.WHRO.16.5.4 Outline the major roles of fats in the body, including a discussion of essential fatty acids and the omega fatty acids.

 

9. The body uses the longer omega-3 and omega-6 fatty acids to make substances known as ____________________.

 

ANS:  eicosanoids

 

DIF:    Bloom’s: Remember                        REF:   5.4 Lipids in the Body

OBJ: UNUT.WHRO.16.5.4 Outline the major roles of fats in the body, including a discussion of essential fatty acids and the omega fatty acids.

 

10. The DRI suggest that linoleic acid provide ____________________ of the daily energy intake and linolenic acid ____________________.

 

ANS:  5 to 10 percent; 0.6 to 1.2 percent

 

DIF:    Bloom’s: Remember

REF:   5.6 Health Effects and Recommended Intakes of Monounsaturated and Polyunsaturated Fats

OBJ: UNUT.WHRO.16.5.6 Explain the relationships between monounsaturated and polyunsaturated fats and health, noting recommendations.

 

 

 

MATCHING

 

 

a.	Liver	k.	Oleic acid
b.	Olestra	l.	Stearic acid
c.	Micelle	m.	Cholesterol
d.	Aspirin	n.	Potato chips
e.	Lecithin	o.	Tropical oils
f.	Corn oil	p.	Chylomicron
g.	Olive oil	q.	Linolenic acid
h.	Sardines	r.	Cholecystokinin
i.	Pancreas	s.	High-density lipoprotein
j.	Canola oil	t.	Very-low density lipoprotein

 

 

1. An 18-carbon monounsaturated fatty acid

 

2. A source of medium-chain saturated fatty acids

 

3. A long-chain saturated fatty acid

 

4. A good source of monounsaturated fats

 

5. A phospholipid

 

6. Major dietary precursor for vitamin D synthesis

 

7. Source of bile

 

8. Signals the release of bile

 

9. Major source of lipase

 

10. Structure assisting absorption of long-chain fats

 

11. A lipoprotein synthesized within intestinal absorptive cells

 

12. A lipoprotein made primarily by the liver

 

13. The lipoprotein type with the highest percentage of protein

 

14. Slows the synthesis of eicosanoids

 

15. An essential fatty acid

 

16. Common source of trans-fatty acids

 

17. Good food source of omega-3 fatty acids

 

18. Good food source of omega-6 fatty acids

 

19. Fat replacement product made from fat

 

20. Oil that is characteristic of the Mediterranean diet

 

1. ANS:  K                    DIF:    Bloom’s: Remember

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

2. ANS:  O                    DIF:    Bloom’s: Remember

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

3. ANS:  L                    DIF:    Bloom’s: Remember

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

4. ANS:  J                     DIF:    Bloom’s: Remember

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

5. ANS:  E                    DIF:    Bloom’s: Remember

REF:   5.2 The Chemist’s View of Phospholipids and Sterols

OBJ: UNUT.WHRO.16.5.2 Describe the chemistry, food sources, and roles of phospholipids and sterols.

 

6. ANS:  M                   DIF:    Bloom’s: Remember

REF:   5.2 The Chemist’s View of Phospholipids and Sterols

OBJ: UNUT.WHRO.16.5.2 Describe the chemistry, food sources, and roles of phospholipids and sterols.

 

7. ANS:  A                    DIF:    Bloom’s: Remember

REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

8. ANS:  R                    DIF:    Bloom’s: Remember

REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

9. ANS:  I                     DIF:    Bloom’s: Remember

REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

10. ANS:  C                    DIF:    Bloom’s: Remember

REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

11. ANS:  P                    DIF:    Bloom’s: Remember

REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

12. ANS:  T                    DIF:    Bloom’s: Remember

REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

13. ANS:  S                    DIF:    Bloom’s: Remember

REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

14. ANS:  D                    DIF:    Bloom’s: Remember                        REF:   5.4 Lipids in the Body

OBJ: UNUT.WHRO.16.5.4 Outline the major roles of fats in the body, including a discussion of essential fatty acids and the omega fatty acids.

 

15. ANS:  Q                    DIF:    Bloom’s: Remember                        REF:   5.4 Lipids in the Body

OBJ: UNUT.WHRO.16.5.4 Outline the major roles of fats in the body, including a discussion of essential fatty acids and the omega fatty acids.

 

16. ANS:  N                    DIF:    Bloom’s: Remember

REF:   5.5 Health Effects and Recommended Intakes of Saturated Fats, Trans Fats, and Cholesterol

OBJ: UNUT.WHRO.16.5.5 Explain the relationships among saturated fat, trans fat, and cholesterol and chronic diseases, noting recommendations.

 

17. ANS:  H                    DIF:    Bloom’s: Remember

REF:   5.6 Health Effects and Recommended Intakes of Monounsaturated and Polyunsaturated Fats

OBJ: UNUT.WHRO.16.5.6 Explain the relationships between monounsaturated and polyunsaturated fats and health, noting recommendations.

 

18. ANS:  F                    DIF:    Bloom’s: Remember

REF:   5.6 Health Effects and Recommended Intakes of Monounsaturated and Polyunsaturated Fats

OBJ: UNUT.WHRO.16.5.6 Explain the relationships between monounsaturated and polyunsaturated fats and health, noting recommendations.

 

19. ANS:  B                    DIF:    Bloom’s: Remember

REF:   5.6 Health Effects and Recommended Intakes of Monounsaturated and Polyunsaturated Fats

OBJ: UNUT.WHRO.16.5.6 Explain the relationships between monounsaturated and polyunsaturated fats and health, noting recommendations.

 

20. ANS:  G                    DIF:    Bloom’s: Remember

REF:   H-5 High-Fat Foods—Friend or Foe?

OBJ: UNUT.WHRO.16.H-5 Identify which fats support health and which impair it.

 

ESSAY

 

1. What methods are used by the food industry to inhibit rancidity of the unsaturated lipids in foods?

 

ANS:

Manufacturers can protect fat-containing products against rancidity in three ways—none of which are perfect. First, products may be sealed in air-tight, non- metallic containers, protected from light, and refrigerated—an expensive and inconvenient storage system. Second, manufacturers may add antioxidants to compete for the oxygen and thus protect the oil (examples are the additives BHA and BHT and vitamin E). Third, products may undergo a process known as hydrogenation.

 

DIF:    Bloom’s: Understand

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

2. Describe the process of fat hydrogenation and discuss its advantages and disadvantages.

 

ANS:

During hydrogenation, some or all of the points of unsaturation are saturated by adding hydrogen molecules. Hydrogenation offers two advantages. First, it protects against oxidation (thereby prolonging shelf life) by making polyunsaturated fats more saturated. Second, it alters the texture of foods by making liquid vegetable oils more solid (as in margarine and shortening).  Hydrogenated fats improve the texture of foods, making margarines spreadable, pie crusts flaky, and puddings creamy. Total hydrogenation rarely occurs during food processing. Most often, a fat is partially hydrogenated, and some of the double bonds that remain after processing change their configuration from cis to trans.

 

In nature, most double bonds are cis—meaning that the hydrogens next to the double bonds are on the same side of the carbon chain. Only a few fatty acids (notably a small percentage of those found in milk and meat products) naturally occur as trans-fatty acids—meaning that the hydrogens next to the double bonds are on opposite sides of the carbon chain. In the body, trans-fatty acids behave more like saturated fats, increasing blood cholesterol and the risk of heart disease

 

DIF:    Bloom’s: Understand

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

 

3. Discuss the meaning and significance of trans-fatty acids in the diet. List four common food sources.

 

ANS:

In nature, most double bonds are cis—meaning that the hydrogens next to the double bonds are on the same side of the carbon chain. Only a few fatty acids (notably a small percentage of those found in milk and meat products) naturally occur as trans-fatty acids—meaning that the hydrogens next to the double bonds are on opposite sides of the carbon chain. In the body, trans-fatty acids behave more like saturated fats, increasing blood cholesterol and the risk of heart disease.

 

Some research suggests that both naturally occurring and commercially created trans fats change blood lipids similarly; other research suggests that the negative effects are specific to only the commercial trans fats. In any case, the important distinction is that a relatively small amount of trans-fat in the diet comes from natural sources. At current levels of consumption, natural trans fats have little, if any, effect on blood lipids. Some naturally occurring trans-fatty acids, known as conjugated linoleic acids, may even have health benefits. Conjugated linoleic acids are not counted as trans fats on food labels.

 

In the body, trans fats alter blood cholesterol the same way some saturated fats do: they raise LDL cholesterol and lower HDL cholesterol. Limiting the intake of trans fats can improve blood cholesterol and lower the risk of heart disease. To that end, many restaurants and manufacturers have taken steps to eliminate or greatly reduce trans fats in foods. The decrease in trans-fatty acids in the food supply is apparent in a decrease in plasma concentrations of trans-fatty acids in consumers.

 

DIF:    Bloom’s: Understand

REF:   5.1 The Chemist’s View of Fatty acids & Triglycerides | Health Effects and Recommended Intakes of Saturated Fats, Trans Fats, and Cholesterol

OBJ: UNUT.WHRO.16.5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats. | 5.5 Explain the relationships among saturated fat, trans fat, and cholesterol and chronic diseases, noting recommendations.

 

4. Discuss the role of dietary cholesterol and the endogenous production of cholesterol and heart disease. What is meant by “good” and “bad” cholesterol?

 

ANS:

Foods derived from both plants and animals contain sterols, but only those from animals contain significant amounts of cholesterol—meats, eggs, seafood, poultry, and dairy products. Some people, confused about the distinction between dietary cholesterol and blood cholesterol, have asked which foods contain the “good” cholesterol. “Good” cholesterol is not a type of cholesterol found in foods, but it refers to the way the body transports cholesterol in the blood, as explained in a later section of this chapter.

 

Sterols other than cholesterol are naturally found in plants. Being structurally similar to cholesterol, plant sterols interfere with cholesterol absorption. By inhibiting cholesterol absorption, a diet rich in plant sterols lowers blood cholesterol levels. Food manufacturers have fortified foods such as margarine with plant sterols, creating a functional food that helps to reduce blood cholesterol.

 

Many vitally important body compounds are sterols. Among them are bile acids, the sex hormones (such as testosterone androgen, and estrogen), the adrenal hormones (such as cortisol cortisone, and aldosterone), and vitamin D, as well as cholesterol itself. Cholesterol in the body can serve as the starting material for the synthesis of these compounds or as a structural component of cell membranes; more than 90 percent of all the body’s cholesterol is found in the cells. Despite common misconceptions, cholesterol is not a villain lurking in some evil foods—it is a compound the body makes and uses. The chemical structure is the same, but cholesterol that is made in the body is referred to as endogenous, whereas cholesterol from outside the body (from foods) is referred to as exogenous. Right now, as you read, your liver is manufacturing cholesterol from fragments of carbohydrate, protein, and fat. In fact, the liver makes about 800 to 1500 milligrams of cholesterol per day, thus contributing much more to the body’s total than does the diet. For perspective, the Daily Value on food labels for cholesterol is 300 milligrams per day.

 

Cholesterol’s harmful effects in the body occur when it accumulates in the artery walls and contributes to the formation of plaque. These plaque deposits lead to atherosclerosis, a disease that causes heart attacks and strokes.

 

DIF:    Bloom’s: Understand

REF:   5.2 The Chemist’s View of Phospholipids and Sterols | Lipids in the Body

OBJ: UNUT.WHRO.16.5.2 Describe the chemistry, food sources, and roles of phospholipids and sterols. | 5.3 Summarize fat digestion, absorption, and transport.

 

5. Discuss in detail the digestion, absorption, and transport of dietary lipids, including the sterols.

 

ANS:

Fat digestion starts off slowly in the mouth, with some hard fats beginning to melt when they reach body temperature. A salivary gland at the base of the tongue releases an enzyme (lingual lipase) that plays an active role in fat digestion in infants, but a relatively minor role in adults. In infants, this enzyme efficiently digests the short- and medium-chain fatty acids found in milk.

 

In a quiet stomach, fat would float as a layer above the watery components of swallowed food. But whenever food is present, the stomach becomes active. The strong muscle contractions of the stomach propel its contents toward the pyloric sphincter. Some chyme passes through the pyloric sphincter periodically, but the remaining partially digested food is propelled back into the body of the stomach. This churning grinds the solid pieces to finer particles, mixes the chyme, and disperses the fat into small droplets. These actions help to expose the fat for attack by the gastric lipase enzyme—an enzyme that performs best in the acidic environment of the stomach. Still, little fat digestion takes place in the stomach; most of the action occurs in the small intestine.

 

When fat enters the small intestine, it triggers the release of the hormone cholecystokinin (CCK), which signals the gallbladder to release its stores of bile. (Remember that the liver makes bile, and the gallbladder stores bile until it is needed.) Among bile’s many ingredients are bile acids, which are made in the liver from cholesterol and have a similar structure. In addition, bile acids often pair up with an amino acid (a building block of protein). The amino acid end is hydrophilic, and the sterol end is hydrophobic. This structure enables bile to act as an emulsifier, drawing fat molecules into the surrounding watery fluids. There, the fats are fully digested as they encounter lipase enzymes from the pancreas and small intestine.

 

Most of the hydrolysis of triglycerides occurs in the small intestine. The major fat-digesting enzymes are pancreatic lipases; some intestinal lipases are also active. These enzymes remove each of a triglyceride’s outer fatty acids one at a time, leaving a monoglyceride. Occasionally, enzymes remove all three fatty acids, leaving a free molecule of glycerol.

 

Phospholipids are digested similarly—that is, their fatty acids are removed by hydrolysis. The two fatty acids and the remaining glycerol and phosphate fragments are then absorbed. Most sterols can be absorbed as is; if any fatty acids are attached, they are first hydrolyzed off.

 

Most of the bile is reabsorbed from the small intestine and recycled. The other possibility is that some of the bile can be trapped by dietary fibers in the large intestine and excreted. Because cholesterol is needed to make bile, the excretion of bile effectively reduces blood cholesterol. The dietary fibers most effective at lowering blood cholesterol this way are the soluble fibers commonly found in fruits, whole grains, and legumes.

 

Small molecules (glycerol and short- and medium-chain fatty acids) can diffuse easily into the intestinal cells; they are absorbed directly into the bloodstream. Larger molecules (monoglycerides and long-chain fatty acids) are emulsified by bile, forming spherical complexes known as micelles. The micelles diffuse into the intestinal cells, where the monoglycerides and long-chain fatty acids are reassembled into new triglycerides. Within the intestinal cells, the newly made triglycerides and other lipids (cholesterol and phospholipids) are packed with protein into transport vehicles known as chylomicrons. The intestinal cells then release the chylomicrons into the lymphatic system. The chylomicrons glide through the lymph until they reach a point of entry into the bloodstream at the thoracic duct near the heart. The blood carries these lipids to the rest of the body for immediate use or storage. A look at these lipids in the body reveals the kinds of fat the diet has been delivering. The blood, fat stores, and muscle cells of people who eat a diet rich in unsaturated fats, for example, contain more unsaturated fats than those of people who select a diet high in saturated fats.

 

The chylomicrons are one of several clusters of lipids and proteins that are used as transport vehicles for fats. As a group, these vehicles are known as lipoproteins, and they solve the body’s challenge of transporting fat through the watery bloodstream. The body makes four main types of lipoproteins, distinguished by their size and density. Each type contains different kinds and amounts of lipids and proteins. The more lipids, the less dense; the more proteins, the more dense.

 

The chylomicrons are the largest and least dense of the lipoproteins. They transport diet-derived lipids (mostly triglycerides) from the small intestine (via the lymph system) to the rest of the body. Cells all over the body remove triglycerides from the chylomicrons as they pass by, so the chylomicrons get smaller and smaller. Within 14 hours after absorption, most of the triglycerides have been depleted, and only a few remnants of protein, cholesterol, and phospholipid remain. Special protein receptors on the membranes of the liver cells recognize and remove these chylomicron remnants from the blood.

 

Meanwhile, in the liver—the most active site of lipid synthesis—cells are making cholesterol, fatty acids, and other lipid compounds. Ultimately, the lipids made in the liver and those collected from chylomicron remnants are packaged with proteins as a VLDL (very-low-density lipoprotein) and shipped to other parts of the body. As the VLDL travel through the body, cells remove triglycerides. As they lose triglycerides, the VLDL shrink and the proportion of lipids shifts. Cholesterol becomes the predominant lipid, and the lipoprotein becomes smaller and denser. As this occurs, the VLDL becomes an LDL (low-density lipoprotein), loaded with cholesterol, but containing relatively few triglycerides.

 

The LDL circulate throughout the body, making their contents available to the cells of all tissues—muscles (including the heart muscle), fat stores, the mammary glands, and others. The cells take triglycerides, cholesterol, and phospholipids to use for energy, make hormones or other compounds, or build new membranes. Special LDL receptors on the liver cells play a crucial role in the control of blood cholesterol concentrations by removing LDL from circulation.

 

The liver makes HDL (high-density lipoprotein) to remove cholesterol from the cells and carry it back to the liver for recycling or disposal. By efficiently clearing cholesterol, HDL lowers the risk of heart disease. In addition, HDL have anti-inflammatory properties that seem to keep artery-clogging plaque from breaking apart and causing heart attacks.

 

DIF:    Bloom’s: Understand                       REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

6. Compare and contrast the digestion-absorption mechanisms for long-chain vs. short-chain fatty acids.

 

ANS:

Most of the hydrolysis of triglycerides occurs in the small intestine. The major fat-digesting enzymes are pancreatic lipases; some intestinal lipases are also active. These enzymes remove each of a triglyceride’s outer fatty acids one at a time, leaving a monoglyceride. Occasionally, enzymes remove all three fatty acids, leaving a free molecule of glycerol.

 

Phospholipids are digested similarly—that is, their fatty acids are removed by hydrolysis. The two fatty acids and the remaining glycerol and phosphate fragments are then absorbed. Most sterols can be absorbed as is; if any fatty acids are attached, they are first hydrolyzed off.

 

Small molecules (glycerol and short- and medium-chain fatty acids) can diffuse easily into the intestinal cells; they are absorbed directly into the bloodstream. Larger molecules (monoglycerides and long-chain fatty acids) are emulsified by bile, forming spherical complexes known as micelles. The micelles diffuse into the intestinal cells, where the monoglycerides and long-chain fatty acids are reassembled into new triglycerides. Within the intestinal cells, the newly made triglycerides and other lipids (cholesterol and phospholipids) are packed with protein into transport vehicles known as chylomicrons. The intestinal cells then release the chylomicrons into the lymphatic system. The chylomicrons glide through the lymph until they reach a point of entry into the bloodstream at the thoracic duct near the heart. The blood carries these lipids to the rest of the body for immediate use or storage. A look at these lipids in the body reveals the kinds of fat the diet has been delivering. The blood, fat stores, and muscle cells of people who eat a diet rich in unsaturated fats, for example, contain more unsaturated fats than those of people who select a diet high in saturated fats.

 

The chylomicrons are one of several clusters of lipids and proteins that are used as transport vehicles for fats. As a group, these vehicles are known as lipoproteins, and they solve the body’s challenge of transporting fat through the watery bloodstream. The body makes four main types of lipoproteins, distinguished by their size and density. Each type contains different kinds and amounts of lipids and proteins. The more lipids, the less dense; the more proteins, the more dense.

 

The chylomicrons are the largest and least dense of the lipoproteins. They transport diet-derived lipids (mostly triglycerides) from the small intestine (via the lymph system) to the rest of the body. Cells all over the body remove triglycerides from the chylomicrons as they pass by, so the chylomicrons get smaller and smaller. Within 14 hours after absorption, most of the triglycerides have been depleted, and only a few remnants of protein, cholesterol, and phospholipid remain. Special protein receptors on the membranes of the liver cells recognize and remove these chylomicron remnants from the blood.

 

Meanwhile, in the liver—the most active site of lipid synthesis—cells are making cholesterol, fatty acids, and other lipid compounds. Ultimately, the lipids made in the liver and those collected from chylomicron remnants are packaged with proteins as a VLDL (very-low-density lipoprotein) and shipped to other parts of the body. As the VLDL travel through the body, cells remove triglycerides. As they lose triglycerides, the VLDL shrink and the proportion of lipids shifts. Cholesterol becomes the predominant lipid, and the lipoprotein becomes smaller and denser. As this occurs, the VLDL becomes an LDL (low-density lipoprotein), loaded with cholesterol, but containing relatively few triglycerides.

 

The LDL circulate throughout the body, making their contents available to the cells of all tissues—muscles (including the heart muscle), fat stores, the mammary glands, and others. The cells take triglycerides, cholesterol, and phospholipids to use for energy, make hormones or other compounds, or build new membranes. Special LDL receptors on the liver cells play a crucial role in the control of blood cholesterol concentrations by removing LDL from circulation.

 

The liver makes HDL (high-density lipoprotein) to remove cholesterol from the cells and carry it back to the liver for recycling or disposal. By efficiently clearing cholesterol, HDL lowers the risk of heart disease. In addition, HDL have anti-inflammatory properties that seem to keep artery-clogging plaque from breaking apart and causing heart attacks.

 

DIF:    Bloom’s: Understand                       REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

7. Discuss the composition and function of the major circulating lipoproteins.

 

ANS:

The chylomicrons are the largest and least dense of the lipoproteins. They transport diet-derived lipids (mostly triglycerides) from the small intestine (via the lymph system) to the rest of the body. Cells all over the body remove triglycerides from the chylomicrons as they pass by, so the chylomicrons get smaller and smaller. Within 14 hours after absorption, most of the triglycerides have been depleted, and only a few remnants of protein, cholesterol, and phospholipid remain. Special protein receptors on the membranes of the liver cells recognize and remove these chylomicron remnants from the blood.

 

Meanwhile, in the liver—the most active site of lipid synthesis—cells are making cholesterol, fatty acids, and other lipid compounds. Ultimately, the lipids made in the liver and those collected from chylomicron remnants are packaged with proteins as a VLDL (very-low-density lipoprotein) and shipped to other parts of the body. As the VLDL travel through the body, cells remove triglycerides. As they lose triglycerides, the VLDL shrink and the proportion of lipids shifts. Cholesterol becomes the predominant lipid, and the lipoprotein becomes smaller and denser. As this occurs, the VLDL becomes an LDL (low-density lipoprotein), loaded with cholesterol, but containing relatively few triglycerides.

 

The LDL circulate throughout the body, making their contents available to the cells of all tissues—muscles (including the heart muscle), fat stores, the mammary glands, and others. The cells take triglycerides, cholesterol, and phospholipids to use for energy, make hormones or other compounds, or build new membranes. Special LDL receptors on the liver cells play a crucial role in the control of blood cholesterol concentrations by removing LDL from circulation.

 

The liver makes HDL (high-density lipoprotein) to remove cholesterol from the cells and carry it back to the liver for recycling or disposal. By efficiently clearing cholesterol, HDL lowers the risk of heart disease. In addition, HDL have anti-inflammatory properties that seem to keep artery-clogging plaque from breaking apart and causing heart attacks.

 

DIF:    Bloom’s: Understand                       REF:   5.3 Digestion, Absorption, and Transport of Lipids

OBJ: UNUT.WHRO.16.5.3 Summarize fat digestion, absorption, and transport.

 

8. Discuss the functions of lipids in the body. What is the role of the liver in metabolizing and processing fats?

 

ANS:

First and foremost, triglycerides—either from food or from the body’s fat stores—provide the cells with energy. When a person dances all night, her dinner’s triglycerides provide some of the fuel that keeps her moving. When a person loses his appetite, his stored triglycerides fuel much of his body’s work until he can eat again.

 

Linoleic acid is an essential fatty acid and the primary member of the omega-6 fatty acid family. When the body receives linoleic acid from the diet, it can make other members of the omega-6 family—such as the 20-carbon polyunsaturated fatty acid, arachidonic acid. Should a linoleic acid deficiency develop, arachidonic acid, and all other omega-6 fatty acids that derive from linoleic acid, would also become essential and have to be obtained from the diet. A nonessential nutrient (such as arachidonic acid) that must be supplied by the diet in special circumstances (as in a linoleic acid deficiency) is considered a conditionally essential nutrient. Normally, vegetable oils and meats supply enough omega-6 fatty acids to meet the body’s needs.

 

Linolenic acid is an essential fatty acid and the primary member of the omega-3 fatty acid family. Like linoleic acid, linolenic acid cannot be made in the body and must be supplied by foods. Given the 18-carbon linolenic acid, the body can make small amounts of the 20- and 22-carbon members of the omega-3 family, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), respectively. These omega-3 fatty acids play critical roles in the optimal structure and function of cells. Found abundantly in the eyes and brain, the omega-3 fatty acids are essential for normal growth, visual acuity, and cognitive development. They may also play an important role in the prevention and treatment of heart disease.

 

The body uses the longer omega-3 and omega-6 fatty acids to make substances known as eicosanoids. Eicosanoids are a diverse group of more than 100 compounds. Sometimes described as “hormonelike,” eicosanoids differ from hormones in important ways. For one, hormones are secreted in one location and travel to affect cells all over the body, whereas eicosanoids appear to affect only the cells in which they are made or nearby cells in the same localized environment. For another, hormones elicit the same response from all their tar- get cells, whereas eicosanoids often have different effects on different cells.

 

DIF:    Bloom’s: Understand                       REF:   5.4 Lipids in the Body

OBJ: UNUT.WHRO.16.5.4 Outline the major roles of fats in the body, including a discussion of essential fatty acids and the omega fatty acids.

 

9. List the essential fatty acids (EFA) for human beings. What are the signs of EFA deficiency? What is the minimum amount of EFA required to prevent a deficiency? What foods are rich sources of EFA?

 

ANS:

The human body needs fatty acids, and it can make all but two of them—linoleic acid (the 18-carbon omega-6 fatty acid) and linolenic acid (the 18-carbon omega-3 fatty acid). These two fatty acids must be sup- plied by the diet and are therefore essential fatty acids. The cells do not possess the enzymes to make any of the omega-6 or omega-3 fatty acids from scratch, nor can they convert an omega-6 fatty acid to an omega-3 fatty acid or vice versa. Cells can, however, use the 18-carbon member of an omega family from the diet to make the longer fatty acids of that family by forming double bonds (desaturation) and lengthening the chain two carbons at a time (elongation). This is a slow process because the omega-3 and omega-6 families compete for the same enzymes. Too much of a fatty acid from one family can create a deficiency of the other family’s longer fatty acids, which becomes critical only when the diet fails to deliver adequate supplies. Therefore, the most effective way to maintain body supplies of all the omega-6 and omega-3 fatty acids is to obtain them directly from foods—most notably, from vegetable oils, seeds, nuts, fish, and other seafoods.

 

Most diets in the United States and Canada meet the minimum essential fatty acid requirement adequately. Historically, deficiencies have developed only in infants and young children who have been fed fat-free milk and low-fat diets or in hospital clients who have been mistakenly fed formulas that provided no polyunsaturated fatty acids for long periods of time. Classic deficiency symptoms include growth retardation, reproductive failure, skin lesions, kidney and liver disorders, and subtle neurological and visual problems.

 

DIF:    Bloom’s: Understand

REF:   5.4 Lipids in the Body | Health Effects and Recommended Intakes of Monounsaturated and Polyunsaturated Fats

OBJ: UNUT.WHRO.16.5.4 Outline the major roles of fats in the body, including a discussion of essential fatty acids and the omega fatty acids. | 5.6 Explain the relationships between monounsaturated and polyunsaturated fats and health, noting recommendations.

 

10. Discuss the roles of hormone-sensitive lipase and lipoprotein lipase in the metabolism of fats.

 

ANS:

When meals deliver more energy than the body needs, the excess is stored as fat in the adipose cells for later use. An enzyme—lipoprotein lipase (LPL)—hydrolyzes triglycerides from circulating lipoproteins, releasing fatty acids, diglycerides, and monoglycerides into the adipose cells. Enzymes inside the adipose cells reassemble these fatty acids, diglycerides, and mono-glycerides into triglycerides again for storage.

 

After meals, the blood delivers chylomicrons and VLDL loaded with triglycerides to the body’s cells for energy. Fat supplies about 60 percent of the body’s ongoing energy needs during rest.

 

During prolonged light to moderately intense exercise or extended periods of food deprivation, fat may make a slightly greater contribution to energy needs. During energy deprivation, several lipase enzymes (most notably hormone-sensitive lipase) inside the adipose cells respond by dismantling stored triglycerides and releasing the glycerol and fatty acids directly into the blood. Energy-hungry cells anywhere in the body can then capture these compounds and take them through a series of chemical reactions to yield energy, carbon dioxide, and water.

 

A person who fasts (drinking only water) will rapidly metabolize body fat. Even with abundant fat supplies, the person has to obtain some energy from lean protein tissue because the brain, nerves, and red blood cells need glucose—and without carbohydrate, only protein and the small glycerol molecule of a triglyceride can be converted to glucose; fatty acids cannot be. Still, in times of severe hunger and starvation, a fatter person can survive longer than a thinner person thanks to this energy reserve.

 

DIF:    Bloom’s: Understand                       REF:   5.4 Lipids in the Body

OBJ: UNUT.WHRO.16.5.4 Outline the major roles of fats in the body, including a discussion of essential fatty acids and the omega fatty acids.

 

11. Explain the possible links between dietary fat intake and cancer.

 

ANS:

The links between dietary fats and cancer are not as evident as they are for heart disease. Dietary fat does not seem to initiate cancer development but, instead, may promote cancer once it has arisen. Stronger risk factors for cancer include smoking, alcohol, and environmental contaminants.

 

The relationship between dietary fat and the risk of cancer differs for various types of cancers. In the case of breast cancer, evidence has been weak and inconclusive. Some studies indicate an association between dietary fat and breast cancer; more convincing evidence indicates that body fatness contributes to the risk. In the case of colon cancer, limited evidence suggests a harmful association with foods containing animal fats.

 

The relationship between dietary fat and the risk of cancer differs for various types and combinations of fats as well. The increased risk in cancer from fat appears to be due primarily to saturated fats or dietary fat from meats (which is mostly saturated). Fat from milk or fish has not been implicated in cancer risk. Olive oil seems to have a protective effect.

 

DIF:    Bloom’s: Understand

REF:   5.5 Health Effects and Recommended Intakes of Saturated Fats, Trans Fats, and Cholesterol

OBJ: UNUT.WHRO.16.5.5 Explain the relationships among saturated fat, trans fat, and cholesterol and chronic diseases, noting recommendations.

 

12. Discuss the relationship of dietary fats to atherosclerosis. What dietary changes bring about the greatest reductions in blood lipids?

 

ANS:

As mentioned earlier, elevated LDL cholesterol is a major risk factor for cardiovascular disease (CVD). As LDL cholesterol accumulates in the arteries, blood flow becomes restricted and blood pressure rises. The consequences are deadly; in fact, heart disease is the nation’s number-one killer of adults. LDL cholesterol is often used to predict the likelihood of a person’s suffering a heart attack or stroke; the higher the LDL, the earlier and more likely the tragedy. Much of the effort to prevent and treat heart disease focuses on lowering LDL cholesterol.

 

Saturated fats are most often implicated in raising LDL cholesterol. In general, the more saturated fat in the diet, the more LDL cholesterol in the blood. Not all saturated fats have the same cholesterol-raising effect, however. Most notable among the saturated fatty acids that raise blood cholesterol are lauric, myristic, and palmitic acids (12, 14, and 16 carbons, respectively). In contrast, stearic acid (18 carbons) seems to have little or no effect on blood cholesterol. Making such distinctions may be impractical in diet planning, however, because these saturated fatty acids typically appear together in the same foods. In addition to raising blood cholesterol, saturated fatty acids contribute to heart disease by promoting blood clotting. Fats from animal sources (meats, milk, and milk products) are the main sources of saturated fats in most people’s diets. Selecting lean cuts of meat, skinless poultry, and fat-free milk products helps to lower saturated fat intake and the risk of heart disease.

 

Research also suggests an association between dietary trans fats and heart disease. In the body, trans fats alter blood cholesterol the same way some saturated fats do: they raise LDL cholesterol and lower HDL cholesterol. Limiting the intake of trans fats can improve blood cholesterol and lower the risk of heart disease. To that end, many restaurants and manufacturers have taken steps to eliminate or greatly reduce trans fats in foods. The decrease in trans fatty acids in the food supply is apparent in a decrease in plasma concentrations of trans fatty acids in consumers.

 

Unlike saturated fat and trans fat, dietary cholesterol raises blood cholesterol very little, if at all. Less clear is its role in heart disease.

 

Replacing saturated fats with unsaturated fats reduces LDL cholesterol and lowers the risk of heart disease. To replace saturated fats with unsaturated fats, sauté foods in olive oil instead of butter, garnish salads with sunflower seeds instead of bacon, snack on mixed nuts instead of potato chips, use avocado instead of cheese on a sandwich, and eat salmon instead of steak.

 

Research on the different types of fats has spotlighted the many beneficial effects of the omega-3 polyunsaturated fatty acids. Regular consumption of omega-3 fatty acids may help to prevent blood clots, protect against irregular heartbeats, improve blood lipids, and lower blood pressure, especially in people with hypertension or atherosclerosis. In addition, omega-3 fatty acids support a healthy immune system and suppress inflammation.

 

A diet that uses olive oil instead of other fats, especially butter, stick margarine, and meat fats, offers numerous health benefits. Olive oil, canola oil, and other oils rich in monounsaturated fatty acids help to protect against heart disease and stroke by:

Lowering total and LDL cholesterol and not lowering HDL cholesterol or raising triglycerides

Lowering LDL cholesterol susceptibility to oxidation

Lowering blood-clotting factors

Providing phytochemicals that act as antioxidants

Lowering blood pressure

Interfering with the inflammatory response

 

Tree nuts and peanuts are traditionally excluded from low-fat diets, and for good reasons. Nuts provide up to 80 percent of their kcalories from fat, and a quarter cup (about an ounce) of mixed nuts provides more than 200 kcalories. Frequent nut consumption (1-ounce serving of nuts on five or more days a week), however, protects against heart disease.

 

Research into the health benefits of the long-chain omega-3 poly-unsaturated fatty acids began with a simple observation: the native peoples of Alaska, northern Canada, and Greenland, who eat a traditional diet rich in omega-3 fatty acids, notably EPA (eicosapentaenoic acid) and DHA (docosaheaenoic acid), have a remarkably low rate of heart disease even though their diets are relatively high in fat. These omega-3 fatty acids help to protect against heart disease by:

Reducing blood triglycerides

Stabilizing plaque

Lowering blood pressure and resting heart rate

Reducing inflammation

Serving as precursors to eicosanoids

 

The number-one dietary determinant of LDL cholesterol is saturated fat. Each 1 percent increase in energy from saturated fatty acids in the diet produces a 2 percent jump in heart disease risk by elevating LDL cholesterol. Conversely, reducing saturated fat intake by  1 percent can be expected to produce a 2 percent drop in heart disease risk by the same mechanism. Even a 2 percent drop in LDL represents a significant improvement for heart health. Like saturated fats, trans fats also raise heart disease risk by elevating LDL cholesterol. A heart-healthy diet limits foods rich in these two types of fat.

 

DIF:    Bloom’s: Understand

REF:   5.4 Lipids in the Body | Health Effects and Recommended Intakes of Saturated Fats, Trans Fats, and Cholesterol | Health Effects and Recommended Intakes of Monounsaturated and Polyunsaturated Fats

OBJ: UNUT.WHRO.16.5.4 Outline the major roles of fats in the body, including a discussion of essential fatty acids and the omega fatty acids. | 5.5 Explain the relationships among saturated fat, trans fat, and cholesterol and chronic diseases, noting recommendations. | 5.6 Explain the relationships between monounsaturated and polyunsaturated fats and health, noting recommendations.

 

13. Explain the position of the American Heart Association concerning intake of butter and margarine.

 

ANS:

The American Heart Association has stated that because butter is rich in both saturated fat and cholesterol whereas margarine is made from vegetable fat with no dietary cholesterol, margarine is still preferable to butter. Be aware that soft margarines (liquid or tub) are less hydrogenated and relatively lower in trans-fatty acids; consequently, they do not raise blood cholesterol as much as the saturated fats of butter or the trans fats of hard (stick) margarines do. Many manufacturers are now offering nonhydrogenated margarines that are “trans-fat free.” In addition, manufacturers have developed margarines fortified with plant sterols that lower blood cholesterol.

 

DIF:    Bloom’s: Understand

REF:   5.6 Health Effects and Recommended Intakes of Monounsaturated and Polyunsaturated Fats

OBJ: UNUT.WHRO.16.5.6 Explain the relationships between monounsaturated and polyunsaturated fats and health, noting recommendations.

 

14. How are omega-3 fats thought to protect against heart disease?

 

ANS:

Research into the health benefits of the long-chain omega-3 poly- unsaturated fatty acids began with a simple observation: the native peoples of Alaska, northern Canada, and Greenland, who eat a traditional diet rich in omega-3 fatty acids, notably EPA (eicosapentaenoic acid) and DHA (docosaheaenoic acid), have a remarkably low rate of heart disease even though their diets are relatively high in fat. These omega-3 fatty acids help to protect against heart disease by:

Reducing blood triglycerides

Stabilizing plaque

Lowering blood pressure and resting heart rate

Reducing inflammation

Serving as precursors to eicosanoids

 

Research studies have provided strong evidence that increasing omega-3 fatty acids in the diet supports heart health and lowers the rate of deaths from heart disease. For this reason, the American Heart Association recommends including fish in a heart-healthy diet. People who eat some fish each week can lower their risks of heart attack and stroke.

 

DIF:    Bloom’s: Understand                       REF:   H-5 High-Fat Foods—Friend or Foe?

OBJ: UNUT.WHRO.16.H-5 Identify which fats support health and which impair it.

 

15. Describe the content of traditional Mediterranean diets and explain the benefits of these foods to cardiovascular health.

 

ANS:

The links between good health and traditional Mediterranean eating patterns of the mid-1900s were introduced earlier with regard to olive oil. For people who eat these diets, the incidence of heart disease, some cancers, diabetes, and other chronic inflammatory diseases is low, and life expectancy is high. Some research suggests that the health benefits of the Mediterranean eating pattern are partially due to its favorable effects on body weight.

Although each of the many countries that border the Mediterranean Sea has its own culture, traditions, and dietary habits, their similarities are much greater than the use of olive oil alone. In fact, no one factor alone can be credited with reducing disease risks—the association holds true only when the overall eating pattern is present. Apparently, each of the foods contributes small benefits that harmonize to produce either a substantial cumulative or synergistic effect.

The Mediterranean eating pattern features fresh, whole foods. The people select crusty breads, whole grains, potatoes, and pastas; a variety of vegetables (including wild greens) and legumes; feta and mozzarella cheeses and yogurt; nuts; and fruits (especially grapes and figs). They eat some fish, other seafood, poultry, a few eggs, and little meat. Along with olives and olive oil, their principal sources of fat are nuts and fish; they rarely use butter or encounter hydrogenated fats. They commonly use herbs and spices instead of salt. Consequently, traditional Mediterranean diets are:

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 that support good health

 

As a result, lipid profiles improve, inflammation diminishes, and the risk of heart disease declines. People following the traditional Mediterranean diet can receive as much as 40 percent of a day’s kcalories from fat, but their limited consumption of milk and milk products and meats provides less than 10 percent from saturated fats. In addition, because the animals in the Mediterranean region pasture-graze, the meat, milk and milk products, and eggs are richer in omega-3 fatty acids than those from animals fed grain.

 

DIF:    Bloom’s: Understand                       REF:   H-5 High-Fat Foods—Friend or Foe?

OBJ: UNUT.WHRO.16.H-5 Identify which fats support health and which impair it.