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Chapter 10 – The Water-Soluble Vitamins: B Vitamins and Vitamin C
MULTIPLE CHOICE
1. Which of the following is a feature of vitamins?
a. Many serve in the role of enzyme inhibitors.
b. Structurally, many are found linked together.
c. Several may be oxidized to yield 4 kcalories per gram.
d. The quantities present in foods are measured in micrograms or milligrams.
e. Some are both water- and fat-soluble.
ANS: D
DIF: Bloom's: Remember
REF: 10.1 The Vitamins—an
Overview
OBJ: UNUT.WHRO.16.10.1 Describe how vitamins differ from the energy nutrients and how
fat-soluble vitamins differ from water-soluble vitamins.
2. What is a precursor?
a. A conditionally essential vitamin
b. A sign or symptom of a clinical vitamin deficiency disorder
c. A substance that is used to synthesize another compound
d. A substance that is recycled through the liver and intestines
e. A sign or symptom of a subclinical vitamin deficiency disorder
ANS: C
DIF: Bloom's: Remember
REF: 10.1 The Vitamins—an
Overview
OBJ: UNUT.WHRO.16.10.1 Describe how vitamins differ from the energy nutrients and how
fat-soluble vitamins differ from water-soluble vitamins.
3. What is meant by the bioavailability of a vitamin in food?
a. The total amount available from plant and animal food
b. The amount absorbed and subsequently used by the body
c. The amount that escapes destruction from food processing
d. The number of different chemical forms of the same vitamin
e. The number of kcal that can be produced from the vitamin
ANS: B
DIF: Bloom's: Remember
REF: 10.1 The Vitamins—an
Overview
OBJ: UNUT.WHRO.16.10.1 Describe how vitamins differ from the energy nutrients and how
fat-soluble vitamins differ from water-soluble vitamins.
4. Milk and milk products provide much of the ____ in people’s diets.
a. Thiamin
b. Vitamin A
c. Riboflavin
d. Vitamin B12
e. Vitamin C
ANS: C
DIF: Bloom's: Remember
REF: 10.1 The Vitamins—an
Overview
OBJ: UNUT.WHRO.16.10.1 Describe how vitamins differ from the energy nutrients and how
fat-soluble vitamins differ from water-soluble vitamins.
5. What is the primary excretory route for the water-soluble vitamins?
a. Bile
b.
c.
d.
e.
Kidney
Intestine
Perspiration
Feces
ANS: B
DIF: Bloom's: Remember
REF: 10.1 The Vitamins—an
Overview
OBJ: UNUT.WHRO.16.10.1 Describe how vitamins differ from the energy nutrients and how
fat-soluble vitamins differ from water-soluble vitamins.
6. What is a chief function of the B vitamins?
a. Antioxidation
b. Anticoagulation
c. Antibody stabilization
d. Coenzyme participation
e. Reproductive support
ANS: D
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
7. Which of the following functions has a requirement for thiamin?
a. Blood coagulation
b. Formation of red blood cells
c. Energy release from energy-yielding nutrients
d. Formation of epithelial cell mucopolysaccharides
e. Production of histamine
ANS: C
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
8. Which of the following is the coenzyme form of thiamin?
a. Thiaminacide
b. Thiamin pyrophosphate
c. Thiamin adenine dinucleotide
d. Thiamin mononucleotide
e. Thiamin flavin
ANS: B
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
9. Beriberi results from a deficiency of
a. niacin.
b. thiamin.
c. vitamin C.
d. vitamin B12.
e. riboflavin.
ANS: B
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
10. Which of the following diets is most likely to lead to beriberi?
a.
b.
c.
d.
e.
High intakes of white rice
Low intakes of whole grains
High intakes of unrefined rice
Low intakes of enriched grains
High intakes of corn
ANS: A
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
11. The Wernicke-Korsakoff syndrome may be treated with supplements of
a. folacin.
b. thiamin.
c. vitamin C.
d. vitamin B12.
e. niacin.
ANS: B
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
12. Which of the following is a characteristic of thiamin nutrition?
a. It contains pyrosulfate.
b. It is required for regeneration of folate
c. It is required for regeneration of niacin
d. It is an integral part of the nerve cell membrane
e. It is integral in carrying activated carbon dioxide.
ANS: D
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
13. Which of the following provides the most thiamin per serving size?
a. Ham
b. Squash
c. Whole milk
d. Whole-grain breads
e. Cheddar cheese
ANS: A
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
14. How does the method of cooking affect thiamin stability?
a. Microwaving the food conserves much of the thiamin.
b. Prolonged heating of the food has little, if any, effect on the thiamin.
c. Boiling the food tends to conserve thiamin by forming a stable, hydrated complex.
d. Steaming the food can lead to substantial thiamin loss due to the high heat needed to form
the steam.
e. Blanching the food before cooking it will preserve thiamin content.
ANS: A
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
15. Which of the following contains the highest concentration of thiamin?
a. Pork
b. Fish
c. Beef
d. Chicken
e. Tofu
ANS: A
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
16. Which of the following is indicative of a dietary deficiency of riboflavin?
a. Beriberi
b. Diarrhea
c. Keratomalacia
d. Inflamed mouth membranes
e. Facial clefts
ANS: D
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
17. Which of the following contains the highest amount of riboflavin when expressed per kcalorie?
a. Cheddar cheese
b. Pinto beans
c. Tuna (in water)
d. Liver
e. Strawberries
ANS: D
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
18. The signs and symptoms of riboflavin deficiency are known collectively as
a. pellagra.
b. antiflavonosis.
c. ariboflavinosis.
d. flavin adenine dinucleosis.
e. beriberi.
ANS: C
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
19. Riboflavin needs are more difficult to meet when the diet is low in
a. meats.
b. grains.
c. vegetables.
d. dairy foods.
e. fruits.
ANS: D
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
20. The coenzyme FAD is formed from what vitamin?
a. Niacin
b. Choline
c. Thiamin
d. Riboflavin
e. Pantothenic acid
ANS: D
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
21. Of the following commonly eaten foods, which makes the greatest contribution to riboflavin intake?
a. Milk
b. Potatoes
c. Orange juice
d. Peanut butter
e. Carrots
ANS: A
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
22. A deficiency of what vitamin produces a characteristic cracking and redness at the corners of the
mouth?
a. Biotin
b. Niacin
c. Riboflavin
d. Ascorbic acid
e. B6
ANS: C
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
23. Which of the following is a property of riboflavin in nutrition?
a. Stability to heat is good.
b. Deficiency leads to beriberi.
c. Requirements are proportional to body weight.
d. Significant amounts are found in citrus products.
e. Stability to irradiation is good.
ANS: A
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
24. Which of the following is a property of niacin in nutrition?
a. It is susceptible to destruction in foods exposed to light
b. It participates primarily in reactions involving amino acids
c. It is soluble in both water and lipids depending upon its chemical form
d. It can be synthesized in the body from the essential amino acid tryptophan
e. It can increase LDL and decrease HDL in large doses.
ANS: D
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
25. When the diet contains an adequate amount of protein, what amino acid can be used by the body to
synthesize niacin?
a. Lysine
b. Valine
c. Tryptophan
d. Phenylalanine
e. Glycine
ANS: C
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
26. Which of the following nutrients functions to prevent the appearance of a bilateral, symmetrical
dermatitis, primarily on areas exposed to the sun?
a. Niacin
b. Choline
c. Inositol
d. Riboflavin
e. Vitamin C
ANS: A
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
27. What vitamin deficiency disease appeared in people who had subsisted on a diet high in corn and low
in protein?
a. Scurvy
b. Pellagra
c. Wet beriberi
d. Pernicious anemia
e. Scaly dermatitis
ANS: B
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
28. Which of the following overt side effect(s) is likely to appear after a person ingests a high quantity of
nicotinic acid?
a. Constipation
b. Mental confusion
c. Painful, tingling, itching sensation
d. Hair loss, bloating, and photophobia
e. Sudden increase in blood pressure
ANS: C
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
29. Which of the following is a feature of niacin nutrition?
a. Low doses may lead to kidney stones.
b. High doses may lower blood cholesterol.
c. Low doses may lead to heartburn and low blood pressure.
d. High doses may elevate red blood cell count in mildly anemic individuals.
e. High doses may cause hypoglycemia.
ANS: B
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
30. Your friend Jane just returned from the doctor, who diagnosed her with a specific vitamin B toxicity.
However, she doesn't recall the name of the vitamin. Which of the following is the only possible
culprit associated with toxicity symptoms?
a. Niacin
b. Biotin
c. Riboflavin
d. Vitamin B12
e. Thiamin
ANS: A
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
31. Among the following, which would be the best source of niacin equivalents?
a. Milk
b. Broccoli
c. Chicken
d. Strawberries
e. Whole wheat bread
ANS: C
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
32. Which of the following is a feature of pantothenic acid in nutrition?
a. Absorption from foods is inhibited by aspirin.
b. A deficiency or a toxicity shows similar symptoms.
c. Deficiencies are seen primarily in children ages 4-10 years.
d. It functions in the metabolism of amino acids, glucose, and fatty acids.
e. It is possible to develop toxic levels on pantothenic acid if too much is ingested.
ANS: D
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
33. Which of the following foods contains a protein that decreases bioavailability of biotin?
a. Aged wine
b. Aged cheese
c. Raw egg whites
d. Raw cauliflower
e. Citrus fruits
ANS: C
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
34. Biotin can be synthesized by
a. avidin.
b. the skin.
c. the liver.
d. intestinal bacteria.
e. bone marrow.
ANS: D
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
35. Which of the following vitamins is known to sustain substantial losses during processing of food?
a. Biotin
b. Niacin
c. Vitamin B12
d. Pantothenic acid
e. Inositol
ANS: D
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
36. Which of the following vitamins is stored primarily in muscle tissue?
a. Biotin
b. Folate
c. Vitamin B6
d. Pantothenic acid
e. Thiamin
ANS: C
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
37. What vitamin is involved intensively in amino acid metabolism?
a. Biotin
b. Vitamin A
c. Vitamin B6
d. Riboflavin
e. Vitamin C
ANS: C
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
38. A common drug for the treatment of tuberculosis is known to markedly interfere in the metabolism of
vitamin
a. B2.
b. B6.
c. B12.
d. C.
e. D.
ANS: B
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
39. Irreversible nerve damage has been reported in people taking large doses of vitamin
a. B1.
b. B2.
c. B6.
d. B7.
e. B12.
ANS: C
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
40. In what major way does alcohol intake affect vitamin B6 metabolism?
a. It reduces acetaldehyde formation.
b. It increases fecal excretion of the vitamin.
c. It dislodges the PLP coenzyme from its enzyme.
d. It interferes with synthesis of the PLP coenzyme.
e. It increases urinary excretion of B6.
ANS: C
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
41. On a per-kcalorie basis, which of the following foods is richest in vitamin B6?
a. Meats
b. Fruits
c. Legumes
d. Grains
e. Dairy
ANS: B
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
42. Pteroylglutamic acid is known as
a. folate.
b. choline.
c. inositol.
d. pyridoxamine.
e. niacin.
ANS: A
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
43. Which of the following vitamins undergoes significant enterohepatic circulation?
a. Folate
b. Niacin
c. Thiamin
d. Pyridoxine
e. Pantothenic acid
ANS: A
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
44.
Which of the following vitamins is usually found in a form that is bound to one or more
pteroylglutamic acid molecules in food?
a. Folate
b.
c.
d.
e.
Thiamin
Vitamin B6
Ascorbic acid
Vitamin B12
ANS: A
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
45. A person with a disorder that limits absorption of bile is at increased risk for deficiency of
a. folate.
b. niacin.
c. riboflavin.
d. ascorbic acid.
e. pantothenic acid
ANS: A
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
46. Research has shown that the risk for neural tube defects is lowered by taking supplements of
a. niacin.
b. folate.
c. vitamin C.
d. vitamin B12.
e. thiamin.
ANS: B
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
47. Which of the following is true regarding B vitamins and homocysteine metabolism?
a. Folate catabolyzes homocysteine
b. Biotin supplements reduce blood homocysteine levels
c. Excessive homocysteine intake reduces vitamin B12 absorption
d. High blood homocysteine levels correlate with reduced incidence of colon cancer
e. High folate levels are necessary for the synthesis of homocysteine
ANS: A
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
48. What vitamin contains cobalt?
a. A
b. B6
c. B12
d. Pantothenic acid
e. Ascorbic acid
ANS: C
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
49. A deficiency of which of the following vitamins results in accumulation of homocysteine in the blood?
a. Folate
b.
c.
d.
e.
Biotin
Niacin
Vitamin K
Vitamin C
ANS: A
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
50. What vitamin is involved mainly with the replacement of red blood cells and digestive tract cells?
a. Folate
b. Niacin
c. Thiamin
d. Riboflavin
e. Choline
ANS: A
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
51. Which of the following is representative of folate availability in foods?
a. Good sources are dairy products and meats.
b. Poor sources are fruit juices and vegetable juices.
c. Much of the vitamin is lost due to heat and oxidation.
d. Only about 10% of the amount in foods is bioavailable.
e. Legumes, nuts, and seeds have very little folate.
ANS: C
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
52. Which of the following foods is highest in folate?
a. Meats
b. Starches
c. Dairy products
d. Green, leafy vegetables
e. Fruits
ANS: D
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
53. What is the most likely reason for the development of a vitamin B12 deficiency?
a. Inadequate intake
b. Increased excretion
c. Inadequate absorption
d. Increased losses in food preparation
e. Inadequate digestion
ANS: C
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
54. Pernicious anemia results from a deficiency of
a. folate.
b.
c.
d.
e.
selenium.
vitamin B12.
iron and copper.
vitamin B6.
ANS: C
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
55. The absorption of which of the following vitamins is most affected by the disorder atrophic gastritis?
a. Choline
b. Vitamin C
c. Vitamin B12
d. Pantothenic acid
e. Vitamin E
ANS: C
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
56. Normally, the body's storage and re-utilization of vitamin B12 prevents a primary or secondary
deficiency from occurring until after about
a. 3 days.
b. 3 weeks.
c. 3 months.
d. 1 year.
e. 3 years.
ANS: E
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
57. Of the following foods, which would be the only source of vitamin B12?
a. Pecans
b. Hot dog
c. Cauliflower
d. Whole-grain bread
e. Plain soy or rice milk
ANS: B
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
58. Which of the following vitamins has an RDA?
a. Biotin
b. Choline
c. Cobalamin
d. Pantothenic acid
e. Carnitine
ANS: C
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
59. Which of the following is a feature of choline in nutrition?
a.
b.
c.
d.
e.
It is an analog of ascorbic acid.
It is abundant in green leafy vegetables.
The body can synthesize it from cysteine.
Average intakes in the United States are lower than recommended.
There is no RDA for it.
ANS: D
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
60. What is a free radical?
a. An inactive vitamin
b. An unphosphorylated vitamin
c. A molecule of unbound cobalamins
d. A molecule with at least one unpaired electron
e. A nonbound vitamin
ANS: D
DIF: Bloom's: Remember
REF: 10.3 Vitamin C
OBJ: UNUT.WHRO.16.10.3 Identify the main roles, deficiency symptoms, and food sources for
vitamin C.
61. Which of the following is a general function of vitamin C?
a. Antiviral agent
b. Antifungal agent
c. Anticancer agent
d. Antioxidant agent
e. Emulsifying agent
ANS: D
DIF: Bloom's: Remember
REF: 10.3 Vitamin C
OBJ: UNUT.WHRO.16.10.3 Identify the main roles, deficiency symptoms, and food sources for
vitamin C.
62. The synthesis of collagen requires both vitamin C and
a. iron.
b. zinc.
c. cobalamin.
d. beta-carotene.
e. copper.
ANS: A
DIF: Bloom's: Remember
REF: 10.3 Vitamin C
OBJ: UNUT.WHRO.16.10.3 Identify the main roles, deficiency symptoms, and food sources for
vitamin C.
63. What organ stores the highest concentration of vitamin C?
a. Liver
b. Muscle
c. Thyroid gland
d. Adrenal glands
e. Hypothalamus
ANS: D
DIF: Bloom's: Remember
REF: 10.3 Vitamin C
OBJ: UNUT.WHRO.16.10.3 Identify the main roles, deficiency symptoms, and food sources for
vitamin C.
64. Why might vitamin C supplements be beneficial in treating the common cold?
a.
b.
c.
d.
e.
They deactivate histamine.
They reduce episodes of diarrhea.
They destroy intestinal pathogens.
They alter hypothalamic control of body temperature.
They improve blood oxygenation.
ANS: A
DIF: Bloom's: Remember
REF: 10.3 Vitamin C
OBJ: UNUT.WHRO.16.10.3 Identify the main roles, deficiency symptoms, and food sources for
vitamin C.
65. Which of the following is an early sign of vitamin C deficiency?
a. Bleeding gums
b. Pernicious anemia
c. Appearance of a cold
d. Hysteria and depression
e. Oily skin
ANS: A
DIF: Bloom's: Remember
REF: 10.3 Vitamin C
OBJ: UNUT.WHRO.16.10.3 Identify the main roles, deficiency symptoms, and food sources for
vitamin C.
66. Which of the following food groups is a rich source of vitamin C?
a. Milk group
b. Meat group
c. Fruit group
d. Grains group
e. Oils group
ANS: C
DIF: Bloom's: Remember
REF: 10.3 Vitamin C
OBJ: UNUT.WHRO.16.10.3 Identify the main roles, deficiency symptoms, and food sources for
vitamin C.
67. Which of the following would be a very good source of vitamin C for the lacto-ovo-vegetarian?
a. Milk
b. Eggs
c. Broccoli
d. Whole-grain bread
e. Bananas
ANS: C
DIF: Bloom's: Remember
REF: 10.3 Vitamin C
OBJ: UNUT.WHRO.16.10.3 Identify the main roles, deficiency symptoms, and food sources for
vitamin C.
68. Approximately what percentage of the U.S. population takes a multivitamin-mineral supplement
regularly?
a. 10
b. 20
c. 30
d. 40
e. 50
ANS: D
DIF: Bloom's: Remember
REF: H-10 Vitamin and Mineral Supplements
OBJ: UNUT.WHRO.16.10.4 Present arguments for and against the use of dietary supplements
69. What nutrient is responsible for causing the most accidental ingestion deaths in children?
a. Iron
b. Calcium
c. Vitamin A
d. Vitamin D
e. Magnesium
ANS: A
DIF: Bloom's: Remember
REF: H-10 Vitamin and Mineral Supplements
OBJ: UNUT.WHRO.16.10.4 Present arguments for and against the use of dietary supplements
70. If a dietary supplement poses a significant risk of illness to consumers, what agency must prove harm
before removing the product from the market?
a. FDA
b. CDC
c. USDA
d. USPHS
e. DHHS
ANS: A
DIF: Bloom's: Remember
REF: H-10 Vitamin and Mineral Supplements
OBJ: UNUT.WHRO.16.10.4 Present arguments for and against the use of dietary supplements
MATCHING
a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
Pork
Corn
Dairy
Folate
Biotin
Niacin
Choline
Anemia
Collagen
Beriberi
k.
l.
m.
n.
o.
p.
q.
r.
s.
t.
Broccoli
Riboflavin
Vitamin B6
Vitamin B12
Tryptophan
Iron overload
Ascorbic acid
Intrinsic factor
Ultraviolet light
Pantothenic acid
Name of thiamin deficiency disease
A food unusually rich in thiamin
Exposure to this leads to destruction of riboflavin
A food source that supplies a substantial amount of people's riboflavin intake
Deficiency of this vitamin leads to cracks and redness at corners of the mouth
Used for synthesis of niacin
Overconsumption of this food has resulted in pellagra
High doses are known to lower LDL cholesterol
Deficiency of this vitamin is induced by feeding raw egg whites
This vitamin is a component of acetyl CoA
Toxicity from this vitamin is known to cause nerve damage and inability to walk
Prevention of neural tube defects is related to increased intake of this substance by pregnant women
One of the first symptoms of folate deficiency
Required to maintain nerve fiber sheath
Required for absorption of vitamin B12
Made in the body from methionine
17.
18.
19.
20.
The antiscorbutic factor
Vitamin C is required for the synthesis of this substance
Excess intake of vitamin C may aggravate this disorder
A concentrated source of vitamin C
1. ANS: J
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
2. ANS: A
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
3. ANS: S
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
4. ANS: C
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
5. ANS: L
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
6. ANS: O
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
7. ANS: B
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
8. ANS: F
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
9. ANS: E
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
10. ANS: T
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
11. ANS: M
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
12. ANS: D
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
13. ANS: H
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
14. ANS: N
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
15. ANS: R
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
16. ANS: G
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, & food sources for each of
the B vitamins.
17. ANS: Q
DIF: Bloom's: Remember
REF: 10.3 Vitamin C
OBJ: UNUT.WHRO.16.10.3 Identify the main roles, deficiency symptoms, and food sources for
vitamin C.
18. ANS: I
DIF: Bloom's: Remember
REF: 10.3 Vitamin C
OBJ: UNUT.WHRO.16.10.3 Identify the main roles, deficiency symptoms, and food sources for
vitamin C.
19. ANS: P
DIF: Bloom's: Remember
REF: 10.3 Vitamin C
OBJ: UNUT.WHRO.16.10.3 Identify the main roles, deficiency symptoms, and food sources for
vitamin C.
20. ANS: K
DIF: Bloom's: Remember
REF: 10.3 Vitamin C
OBJ: UNUT.WHRO.16.10.3 Identify the main roles, deficiency symptoms, and food sources for
vitamin C.
COMPLETION
1. Compounds that can be converted to vitamins in the body are called ____________________.
ANS: precursors; provitamins
DIF: Bloom's: Remember
REF: 10.1 The Vitamins—an Overview
OBJ: UNUT.WHRO.16.10.1 Describe how vitamins differ from the energy nutrients and how
fat-soluble vitamins differ from water-soluble vitamins.
2. Water-soluble vitamins are absorbed directly into ____________________.
ANS: blood
DIF: Bloom's: Remember
REF: 10.1 The Vitamins—an Overview
OBJ: UNUT.WHRO.16.10.1 Describe how vitamins differ from the energy nutrients and how
fat-soluble vitamins differ from water-soluble vitamins.
3. Prolonged thiamin deficiency can result in the disease ____________________.
ANS: beriberi
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, and food sources for each
of the B vitamins.
4. The niacin-deficiency disease, ____________________, produces the symptoms of diarrhea,
dermatitis, dementia, and eventually death
ANS: pellagra
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, and food sources for each
of the B vitamins.
5. In order to protect against ____________________, all women of childbearing age who are capable of
becoming pregnant should consume 0.4 milligram of folate daily.
ANS: neural tube defects
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, and food sources for each
of the B vitamins.
6. Of all the vitamins, ____________________ appears to be most vulnerable to interactions with drugs,
which can also lead to a secondary deficiency.
ANS: folate
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, and food sources for each
of the B vitamins.
7. Older adults with B12 deficiencies may develop ____________________, a condition that damages the
cells of the stomach.
ANS: atrophic gastritis
DIF: Bloom's: Remember
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, and food sources for each
of the B vitamins.
8. A(n) ____________________ is a molecule with one or more unpaired electrons, which makes it
unstable and highly reactive.
ANS: free radical
DIF: Bloom's: Remember
REF: 10.3 Vitamin C
OBJ: UNUT.WHRO.16.10.3 Identify the main roles, deficiency symptoms, and food sources for
vitamin C.
9. Vitamin C helps to form the fibrous structural protein of connective tissues known as
____________________.
ANS: collagen
DIF: Bloom's: Remember
REF: 10.3 Vitamin C
OBJ: UNUT.WHRO.16.10.3 Identify the main roles, deficiency symptoms, and food sources for
vitamin C.
10. When vitamin C concentrations fall to about a fifth of optimal levels symptoms of
____________________ appear.
ANS: scurvy
DIF: Bloom's: Remember
REF: 10.3 Vitamin C
OBJ: UNUT.WHRO.16.10.3 Identify the main roles, deficiency symptoms, and food sources for
vitamin C.
ESSAY
1. Provide a brief definition of a vitamin.
ANS:
The vitamins differ from carbohydrates, fats, and proteins in the following ways:
Structure. Vitamins are individual units; they are not linked together (as are molecules of glucose or
amino acids).
Function. Vitamins do not yield energy when metabolized; many of them do, however, assist the
enzymes that participate in the release of energy from carbohydrates, fats, and proteins.
Food contents. The amounts of vitamins people ingest from foods and the amounts they require daily
are measured in micrograms (µg) or milligrams (mg), rather than grams (g).
DIF: Bloom's: Understand
REF: 10.1 The Vitamins—an Overview
OBJ: UNUT.WHRO.16.10.1 Describe how vitamins differ from the energy nutrients and how
fat-soluble vitamins differ from water-soluble vitamins.
2. What is meant by the bioavailability of a vitamin? How is it determined?
ANS:
Some water-soluble vitamins are synthesized by GI tract bacteria and absorbed by the large intestine,
but not in quantities great enough to meet the body’s needs; foods must supply these essential
nutrients. The amount of vitamins available from foods depends not only on the quantity provided by a
food but also on the amount absorbed and used by the body—referred to as the vitamins’
bioavailability. The quantity of vitamins in a food can be determined relatively easily. Researchers
analyze foods to determine the vitamin contents and publish the results in tables of food composition.
Determining the bioavailability of a vitamin is a more complex task because it depends on many
factors, including:
Efficiency of digestion and time of transit through the GI tract
Previous nutrient intake and nutrition status
Method of food preparation (raw, cooked, or processed)
Source of the nutrient (synthetic, fortified, or naturally occurring)
Other foods consumed at the same time
DIF: Bloom's: Understand
REF: 10.1 The Vitamins—an Overview
OBJ: UNUT.WHRO.16.10.1 Describe how vitamins differ from the energy nutrients and how
fat-soluble vitamins differ from water-soluble vitamins.
3. Discuss thiamin nutrition including functions, risk factors for deficiency, symptoms of deficiency,
food sources, and stability.
ANS:
Thiamin is the vitamin part of the coenzyme TPP (thiamin pyrophosphate) that assists in energy
metabolism. The TPP coenzyme participates in the conversion of pyruvate to acetyl CoA. Besides
playing these pivotal roles in energy metabolism, thiamin occupies a special site on the membranes of
nerve cells. Consequently, nerve activity and muscle activity in response to nerves depend heavily on
thiamin.
People who fail to eat enough food to meet energy needs risk nutrient deficiencies, including thiamin
deficiency. Inadequate thiamin intakes have been reported among the nation’s malnourished and
homeless people. Similarly, people who derive most of their energy from empty-kcalorie foods and
beverages risk thiamin deficiency. Alcohol provides a good example of how empty kcalories can lead
to thiamin deficiency. Alcohol contributes energy but provides few, if any, nutrients and often
displaces food. In addition, alcohol impairs thiamin absorption and enhances thiamin excretion in the
urine, doubling the risk of deficiency. An estimated four out of five alcoholics are thiamin deficient,
which damages the brain’s structure and impairs its function.
Prolonged thiamin deficiency can result in the disease beriberi, which was first observed in Indonesia
when the custom of polishing rice became widespread. Rice provided 80 percent of the energy intake
of the people of that area, and the germ and bran of the rice grain was their principal source of thiamin.
When the germ and bran were removed in the preparation of white rice, beriberi became rampant.
Meats in the pork family are exceptionally rich in thiamin. Grains— whole grains or enriched—are a
reliable source of thiamin.
Prolonged cooking can destroy thiamin. Also, like other water-soluble vitamins, thiamin leaches into
water when foods are boiled or blanched. Cooking methods that require little or no water such as
steaming and microwave heating conserve thiamin and other water-soluble vitamins.
DIF: Bloom's: Understand
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, and food sources for each
of the B vitamins.
4. Discuss riboflavin nutrition including functions, risk factors for deficiency, symptoms of deficiency,
food sources, and stability.
ANS:
Like thiamin, riboflavin serves as a coenzyme in many reactions, most notably in energy metabolism.
The coenzyme forms of riboflavin are FMN (flavin mononucleotide) and FAD (flavin adenine
dinucleotide); both can accept and then donate two hydrogens.
Riboflavin deficiency most often accompanies other nutrient deficiencies. Lack of the vitamin causes
inflammation of the membranes of the mouth, skin, eyes, and GI tract. Excesses of riboflavin appear to
cause no harm, and no UL has been established.
The greatest contributions of riboflavin come from milk and milk products. Whole-grain or enriched
grains are also valuable sources because of the quantities people typically consume. When riboflavin
sources are ranked by nutrient density (per kcalorie), many dark green, leafy vegetables (such as
broccoli, turnip greens, asparagus, and spinach) appear high on the list.
Ultraviolet light and irradiation destroy riboflavin. For these reasons, milk is sold in cardboard or
opaque plastic containers, instead of clear glass bottles. In contrast, riboflavin is stable to heat, so
cooking does not destroy it.
DIF: Bloom's: Understand
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, and food sources for each
of the B vitamins.
5. What factors are associated with vitamin B12 inadequacy other than low intake?
ANS:
Most vitamin B12 deficiencies reflect inadequate absorption, not poor intake. Inadequate absorption
typically occurs for one of two reasons: a lack of hydrochloric acid or a lack of intrinsic factor.
Without hydrochloric acid, the vitamin is not released from the dietary proteins and so is not available
for binding with the intrinsic factor. Without the intrinsic factor, the vitamin cannot be absorbed.
DIF: Bloom's: Understand
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, and food sources for each
of the B vitamins.
6. Discuss through the use of examples the importance of folate in development of the neural tube during
the early weeks of pregnancy.
ANS:
The brain and spinal cord develop from the neural tube, and defects in its orderly formation during the
early weeks of pregnancy may result in various central nervous system disorders and death.
Folate supplements taken 1 month before conception and continued throughout the first trimester of
pregnancy can help prevent neural tube defects. For this reason, all women of childbearing age who
are capable of becoming pregnant should consume 0.4 milligram (400 micrograms) of folate
daily–easily accomplished by eating folate-rich foods, folate-fortified foods, and a multivitamin
supplement daily. Because half of the pregnancies each year are unplanned and because neural tube
defects occur early in development before most women realize they are pregnant, the Food and Drug
Administration (FDA) has mandated that grain products be fortified to deliver folate to the U.S.
population. Labels on fortified products may claim that “adequate intake of folate has been shown to
reduce the risk of neural tube defects.” Fortification has improved folate status in women of
childbearing age and lowered the prevalence rate of neural tube defects.
Some research suggests that folate taken before and during pregnancy may also prevent congenital
birth defects, such as cleft lip and cleft palate, and neurodevelopmental disorders, such as autism. Such
findings strengthen recommendations for women to pay attention to their folate needs.
DIF: Bloom's: Understand
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, and food sources for each
of the B vitamins.
7. What are the associations between folate intake and development and progression of certain cancers?
ANS:
Because the synthesis of DNA and the transfer of methyl groups depend on folate, its relationships
with cancer are complex, depending on the type of cancer and the timing of folate supplementation.
Some research suggests that sufficient folate may protect against the initiation of cancer, whereas other
studies report that high intakes may enhance progression once cancer has begun. In general, foods
containing folate probably reduce the risk of pancreatic cancer. Limited evidence suggests that folate
may also reduce the risk of esophageal and colorectal cancer.
DIF: Bloom's: Understand
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, and food sources for each
of the B vitamins.
8. Discuss the association between marginal vitamin B12 deficiency and cognitive function.
ANS:
Marginal vitamin B12 deficiency impairs cognition. Advanced neurological symptoms include a
creeping paralysis that begins at the extremities and works inward and up the spine. Early detection
and correction are necessary to prevent permanent nerve damage and paralysis. With sufficient folate
in the diet, the neurological symptoms of vitamin B12 deficiency can develop without evidence of
anemia and the cognitive decline is especially rapid. Such interactions between folate and vitamin B12
highlight some of the safety issues surrounding the use of supplements and the fortification of foods.
No adverse effects have been reported for excess vitamin B12, and no UL has been set.
DIF: Bloom's: Understand
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, and food sources for each
of the B vitamins.
9. Discuss the essentiality of choline, including chief functions and major food sources.
ANS:
Although not defined as a vitamin, choline is an essential nutrient that is commonly grouped with the
B vitamins. The body uses choline to make the neurotransmitter acetylcholine and the phospholipid
lecithin. During fetal development, choline supports the structure and function of the brain and spinal
cord, by supporting neural tube closure and enhancing learning performance.
Choline is found in a variety of common foods such as milk, eggs, and peanuts and as part of lecithin,
a food additive commonly used as an emulsifying agent.
DIF: Bloom's: Understand
REF: 10.2 The B Vitamins
OBJ: UNUT.WHRO.16.10.2 Identify the main roles, deficiency symptoms, and food sources for each
of the B vitamins.
10. Explain the modes of action of vitamin C.
ANS:
As an antioxidant: Vitamin C loses electrons easily, a characteristic that allows it to perform as an
antioxidant. In the body, antioxidants defend against free radicals. A free radical is a molecule with
one or more unpaired electrons, which makes it unstable and highly reactive. Antioxidants can
neutralize free radicals by donating an electron or two. In doing so, antioxidants protect other
substances from free radical damage.
As a cofactor in collagen formation: Vitamin C helps to form the fibrous structural protein of
connective tissues known as collagen. Collagen serves as the matrix on which bones and teeth are
formed. When a person is wounded, collagen glues the separated tissues together, forming scars. Cells
are held together largely by collagen; this is especially important in the walls of the blood vessels,
which must withstand the pressure of blood surging with each beat of the heart.
As a cofactor in other reactions: Vitamin C also serves as a cofactor in the synthesis of several other
compounds. As in collagen formation, vitamin C helps in the hydroxylation of carnitine, a compound
that transports fatty acids, especially long-chain fatty acids, across the inner membrane of
mitochondria in cells. It also participates in the conversions of the amino acids tryptophan and tyrosine
to the neurotransmitters serotonin and norepinephrine, respectively. Vitamin C also assists in the
making of hormones, including thyroxine, which regulates the metabolic rate; when metabolism
speeds up in times of extreme physical stress, the body’s use of vitamin C increases.
In stress: Among the stresses known to increase vitamin C needs are infections; burns; extremely high
or low temperatures; intakes of toxic heavy metals such as lead, mercury, and cadmium; the chronic
use of certain medications, including aspirin, barbiturates, and oral contraceptives; and cigarette
smoking. During stress, the adrenal glands—which contain more vitamin C than any other organ in the
body—release vitamin C and hormones into the blood.
In the prevention and treatment of the common cold: Vitamin C has been a popular option for the
prevention and treatment of the common cold for decades, but research supporting such claims has
been conflicting and controversial. Some studies find no relationship between vitamin C and the
occurrence of the common cold, whereas others report modest benefits—fewer colds, fewer days, and
shorter duration of severe symptoms, especially for those exposed to physical and environmental
stresses. A review of the research on vitamin C in the treatment and prevention of the common cold
reveals a slight, but consistent reduction in the duration of the common cold in favor of those taking a
daily dose of at least 200 milligrams of vitamin C.
In disease prevention: Whether vitamin C may help in preventing or treating cancer, heart disease,
cataract, and other diseases is still being studied
DIF: Bloom's: Understand
REF: 10.3 Vitamin C
OBJ: UNUT.WHRO.16.10.3 Identify the main roles, deficiency symptoms, and food sources for
vitamin C.
11. In what ways have vitamin C supplements been shown to affect nasal congestion from a cold?
ANS:
In the prevention and treatment of the common cold: Vitamin C has been a popular option for the
prevention and treatment of the common cold for decades, but research supporting such claims has
been conflicting and controversial. Some studies find no relationship between vitamin C and the
occurrence of the common cold, whereas others report modest benefits—fewer colds, fewer days, and
shorter duration of severe symptoms, especially for those exposed to physical and environmental
stresses. A review of the research on vitamin C in the treatment and prevention of the common cold
reveals a slight, but consistent reduction in the duration of the common cold in favor of those taking a
daily dose of at least 200 milligrams of vitamin C.
Discoveries about how vitamin C works in the body provide possible links between the vitamin and
the common cold. Anyone who has ever had a cold knows the discomfort of a runny or stuffed-up
nose. Nasal congestion develops in response to elevated blood histamine, and people commonly take
antihistamines for relief. Like an antihistamine, vitamin C comes to the rescue and deactivates
histamine.
DIF: Bloom's: Understand
REF: 10.3 Vitamin C
OBJ: UNUT.WHRO.16.10.3 Identify the main roles, deficiency symptoms, and food sources for
vitamin C.
12. Describe the potential hazards of excessive vitamin C intake.
ANS:
The availability of vitamin C supplements and the publication of books recommending vitamin C to
prevent colds and cancer have led many people to take large doses of vitamin C. Not surprisingly, side
effects of vitamin C supplementation such as gastrointestinal distress and diarrhea have been reported.
The UL for vitamin C was established based on these symptoms.
Several instances of interference with medical regimens are also known. Large amounts of vitamin C
excreted in the urine obscure the results of tests used to detect glucose or ketones in the diagnosis of
diabetes. In some instances, excess vitamin C gives a false positive result; in others, a false negative.
People taking anticlotting medications may unwittingly counteract the effect if they also take massive
doses of vitamin C. Those with kidney disease, a tendency toward gout, or a genetic abnormality that
alters vitamin C’s breakdown to its excretion products are prone to forming kidney stones if they take
large doses of vitamin C. Vitamin C supplements may adversely affect people with iron overload.
Vitamin C enhances iron absorption and releases iron from body stores; too much free iron causes the
kind of cellular damage typical of free radicals. These adverse consequences illustrate how vitamin C
can act as a prooxidant when quantities exceed the body’s needs.
DIF: Bloom's: Understand
REF: 10.3 Vitamin C
OBJ: UNUT.WHRO.16.10.3 Identify the main roles, deficiency symptoms, and food sources for
vitamin C.
13. List population groups that have a physiological need for vitamin/mineral supplements.
ANS:
Correct Overt Deficiencies
In the United States, adults rarely suffer nutrient deficiency diseases such as scurvy, pellagra, and
beriberi, but nutrient deficiencies do still occur. To correct an overt deficiency disease, a physician
may prescribe therapeutic doses two to ten times the RDA (or AI) of a nutrient. At such high doses, the
supplement is having a pharmacological effect and acting as a drug.
Support Increased Nutrient Needs
Nutrient needs increase during certain stages of life, making it difficult to meet some of those needs
without supplementation. For example, women who lose a lot of blood and therefore a lot of iron
during menstruation each month may need an iron supplement. Women of childbearing age need folate
supplements to reduce the risks of neural tube defects. Similarly, pregnant women and women who are
breastfeeding their infants have exceptionally high nutrient needs and so usually need special
supplements. Newborns routinely receive a single dose of vitamin K at birth to prevent abnormal
bleeding. Infants may need other supplements as well, depending on whether they are breastfed or
receiving formula, and on whether the water they drink contains fluoride.
Improve Nutrition Status
In contrast to the classical deficiencies, which present a multitude of symptoms and are relatively easy
to recognize, subclinical deficiencies are subtle and easy to overlook—and they are also more likely to
occur. Without fortification or supplementation, many adults in the United States fall short of
recommended intakes for several vitamins and minerals. People who do not eat enough food to deliver
the needed amounts of nutrients, such as habitual dieters and the elderly, risk developing subclinical
deficiencies. Similarly, vegetarians who restrict their use of entire food groups without appropriate
substitutions may fail to fully meet their nutrient needs. If there is no way for these people to eat
enough nutritious foods to meet their needs, then vitamin-mineral supplements may be appropriate to
help prevent nutrient deficiencies.
Improve the Body’s Defenses
Health-care professionals may provide special supplementation to people being treated for addictions
to alcohol or other drugs and to people with prolonged illnesses, extensive injuries, or other severe
stresses such as surgery. Illnesses that interfere with appetite, eating, or nutrient absorption impair
nutrition status. For example, the stomach condition atrophic gastritis often creates a vitamin B12
deficiency. In addition, nutrient needs are often heightened by diseases or medications. In all these
cases, supplements are appropriate.
Reduce Disease Risks
Few people consume the optimal amounts of all the vitamins and minerals by diet alone. Inadequate
intakes have been linked to chronic diseases such as heart disease, some cancers, and osteoporosis. For
this reason, some physicians recommend that all adults take vitamin- mineral supplements. Such
regular supplementation would provide an optimum intake to enhance metabolic harmony and prevent
disease at relatively little cost. Others recognize the lack of conclusive evidence and the potential harm
of supplementation and advise against such a recommendation. A statement from the National
Institutes of Health acknowledges that evidence is insufficient to recommend either for or against the
use of supplements to prevent chronic diseases.
DIF: Bloom's: Remember
REF: H-10 Vitamin and Mineral Supplements
OBJ: UNUT.WHRO.16.H-10 Present arguments for and against the use of dietary supplements.
14. What type of testing is done by the U.S. Pharmacopeia to assure the quality and safety of certain
vitamin and mineral supplements?
ANS:
Supplements with a USP verification logo have been tested by the US Pharmacopeia (USP) to ensure
that the supplement:
Contains the declared ingredients and amounts listed on the label
Does not contain harmful levels of contaminants
Will disintegrate and release ingredients in the body
Was made under safe and sanitary conditions
DIF: Bloom's: Remember
REF: H-10 Vitamin and Mineral Supplements
OBJ: UNUT.WHRO.16.H-10 Present arguments for and against the use of dietary supplements.
15. Explain the major provisions of the Dietary Supplement Health and Education Act of 1994.
ANS:
Details of supplement regulation are defined in the Dietary Supplement Health and Education Act of
1994, which was intended to enable consumers to make informed choices about dietary supplements.
The act subjects supplements to the same general labeling requirements that apply to foods.
Specifically:
Nutrition labeling for dietary supplements is required.
Labels may make nutrient claims (as “high” or “low”) according to specific criteria (for
example, “an excellent source of vitamin C”).
Labels may claim that the lack of a nutrient can cause a deficiency disease, but if they do, they
must also include the prevalence of that deficiency disease in the United States.
Labels may make health claims that are supported by significant scientific agreement and are not
brand specific (for example, “folate protects against neural tube defects”).
Labels may claim to diagnose, treat, cure, or relieve common complaints such as menstrual
cramps or memory loss, but may not make claims about specific diseases (except as noted
previously).
Labels may make structure-function claims about the role a nutrient plays in the body, how the
nutrient performs its function, and how consuming the nutrient is associated with general
well-being. The manufacturer is responsible for ensuring that the claims are truthful and not
misleading. Claims must be accompanied by an FDA disclaimer statement: “This statement has
not been evaluated by the Food and Drug Administration. This product is not intended to
diagnose, treat, cure, or prevent any disease.”
DIF: Bloom's: Remember
REF: H-10 Vitamin and Mineral Supplements
OBJ: UNUT.WHRO.16.H-10 Present arguments for and against the use of dietary supplements.