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Chapter 11 – The Fat-Soluble Vitamins: A, D, E, and K
Learning Objectives
After completing Chapter 11, the student will be able to:
11.1 Identify the main roles, deficiency symptoms, and food sources for vitamin A.
11.2 Identify the main roles, deficiency symptoms, and sources for vitamin D.
Assignments and Other Instructional Materials
The following ready-to–use assignments are available in this chapter of the instructor’s manual:
• New! Case Study 11-1: Supplemental Vitamin A
• Case Study 11-2: Low Serum Vitamin D
• Worksheet 11-1: Fat-Soluble Vitamins’ Equivalent Measurements
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• New! Worksheet 11-2: Chapter 11 Crossword Puzzle
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• Handout 11-2: The Actions of Free Radicals and Antioxidants
Lecture Presentation Outline
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Key to instructor resource annotations (shown to the right of or below outline topics):
TRA = Transparency acetates: 13e = 13th edition, 12e = 12th edition, 11e = 11th edition, 10e = 10th edition
Website = Available for download from book companion website: HN = student handout
IM = Included in this instructor’s manual: CS = case study, WS = worksheet, CA = classroom activity
Introductory/whole chapter resources: PL figure JPEGs; Test Bank; IM WS 11-1, 11-2, 11-3, HN 10-1
I. Vitamin A and Beta-Carotene (Figures 11-1 and 11-2) – Discuss the following: 10e TRA 118
A. Roles in the Body
1. Vitamin A in Vision (Figure 11-3) 10e TRA 119
a. Cornea
b. Retina
c. Rhodopsin
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2. Vitamin A in Protein Synthesis and Cell Differentiation
a. Cell differentiation
b. Epithelial cells
1. Skin
4. Beta-Carotene as an Antioxidant – Protects the body from diseases
B. Vitamin A Deficiency – Explain deficiency symptoms, including:
1. Infectious Diseases
2. Night Blindness (Figure 11-5)
3. Blindness (Xerophthalmia)
a. Xerophthalmia
b. Xerosis
c. Keratomalacia
4. Keratinization (Figure 11-6)
C. Vitamin A Toxicity – Explain the effects of toxicity Website HN 11-1
1. UL for adults: 3000 g/day
2. Bone Defects
D. Vitamin A Recommendations IM CS 11-1
1. Retinal activity equivalents (RAE)
2. RDA for men: 900 g RAE/day
3. RDA for women: 700 g RAE/day
E. Vitamin A in Foods (Figure 11-8) 10e TRA 121
1. Retinol is found in fortified milk, cheese, cream, butter, fortified margarine, and eggs
2. The Colors of Vitamin A Foods – Beta-carotene sources
a. Spinach and other dark green leafy vegetables
II. Vitamin D (Figure 11-9) – Discuss the following: 13e TRA 14
A. Roles in the Body
1. Vitamin D in Bone Growth
2. Vitamin D in Other Roles
a. Immune system
1. Discuss factors that contribute to deficiency
2. Rickets (Figure 11-10)
a. Affects mainly children worldwide
b. Describe deficiency symptoms
C. Vitamin D Toxicity
1. Discuss toxicity causes and symptoms
2. UL for adults: 100 g/day or 4000 IU/day
3. Toxicity disease is called hypervitaminosis D
D. Vitamin D Recommendations and Sources
1. Current recommendations:
2. Vitamin D in Foods
a. Fortified milk, butter, and margarine
4. Vitamin D from the Sun (Figure 11-11) 13e TRA 14; 10e TRA 124
5. Vitamin D from Supplements – beneficial for some elderly & others with inadequate skin synthesis
III. Vitamin E – Discuss the following:
A. Vitamin E as an Antioxidant 10e TRA 125, 126
1. Stops the chain reaction of free radicals
2. Protection of polyunsaturated fatty acids and vitamin A
3. Protects against the oxidation of LDLs
B. Vitamin E Deficiency
4. Fibrocystic breast disease and intermittent claudication seem to respond to vitamin E treatment
C. Vitamin E Toxicity
2. UL for adults: 1000 mg/day
3. May augment the effects of anticlotting medication
1. Polyunsaturated plant oils such as margarine, salad dressings, and shortenings
2. Leafy green vegetables
3. Wheat germ
IV. Vitamin K – Discuss the following:
A. Roles in the Body
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3. Without vitamin K, a hemorrhagic disease may develop
4. Hemophilia is a hereditary disorder and is not cured with vitamin K
5. Allows osteocalcin to bind to bone minerals
B. Vitamin K Deficiency
3. Newborn infants receive a single dose of vitamin K at birth because of a sterile intestinal tract
C. Vitamin K Toxicity
1. Uncommon
2. No known toxicity symptoms
3. High doses can decrease the effectiveness of anticlotting medications
D. Vitamin K Recommendations and Sources IM CA 11-1
1. AI for men: 120 g/day
V. Highlight: Antioxidant Nutrients in Disease Prevention
A. Free Radicals and Disease – Describe the role of free radicals in disease (Figure H11–1) 11e TRA 24
B. Defending against Free Radicals IM WS 11-4; Website HN 11-2
1. Limiting free radical formation
2. Destroying free radicals or their precursors
C. Defending against Cancer IM CA 11-2
1. Vitamin C seems to protect against esophageal cancer, but acts as a prooxidant at high doses
2. Vitamin E and carotenoids from foods might be protective
D. Defending against Heart Disease
1. Vitamin E reduces LDL oxidation, inflammation, arterial injuries, & blood clotting
2. Vitamin C may reduce LDL oxidation, raise LDL, & lower cholesterol & blood pressure
E. Food, Supplements, or Both?
1. Food and diet
a. Reduce saturated or trans-fat
2. Supplements IM CA 11-3
3. High-antioxidant foods IM CA 11-4
a. Fruits
b. Vegetables
c. Grains
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Case Studies
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Case Study 11-1: Supplemental Vitamin A
Beth H. is a 29-year-old professional woman with a family history of osteoporosis. She weighs 135 pounds and is 66
inches tall. She eats a varied diet that includes meat, fish, and poultry and she consumes at least 2 cups of low-fat
milk or yogurt most days. She drinks a small glass of orange juice every morning and typically eats about 2 cups of
vegetables daily. Every day she takes a daily multivitamin that contains 10,000 IU vitamin A (as beta-carotene), and
now she is wondering if this may be necessary or even harmful.
1. According to the current RDA for vitamin A included in this chapter, how much vitamin A does Beth need each
day?
2. Using the formula in this chapter, show how Beth can convert the vitamin A in her supplement into RAE units.
Then use this formula to calculate the amount of micrograms RAE Beth gets each day from her supplement.
3. Use Figure 11-8 to estimate how much vitamin A (in micrograms RAE) Beth can reasonably expect to receive
from her usual diet.
4. Considering her family history and age, what are reasons that Beth should avoid excessive intakes of vitamin A
in supplement form?
5. What might be Beth’s reasons to continue taking her multivitamin supplement, which contains vitamin A as
beta-carotene?
6. What might be her reasons not to continue taking this supplement?
Answer Key
1. 700 micrograms RAE
Case Study 11-2: Low Serum Vitamin D
Joan is a 90-year-old Caucasian woman who has recently been diagnosed with osteoporosis after a recent fall that
broke her hip. She is 5 feet 4 inches tall and weighs 115 pounds. Lately she has been complaining about muscle pain
in her legs. She eats a limited diet due to a chronic low appetite. A recent blood test shows Joan’s serum vitamin D
level is below normal. Her daily diet includes juice or fruit and toast with butter for breakfast; cottage cheese and
fruit for lunch; and salad or frozen vegetable with meat or poultry for dinner. She dislikes most fish except canned
tuna and she often drinks a glass of milk before going to bed at night. Although she lives in New Mexico, she spends
most days indoors. Joan has been taking a blood-thinning medication since she was discharged from the hospital.
She takes a daily multivitamin that contains 400 IU vitamin D and 15 mg vitamin E.
1. What may be some contributors to Joan’s low vitamin D status?
2. Suggest at least two practical ways for Joan to improve her vitamin D status.
3. Based on her medical history and current medications, what advice would you offer Joan regarding her current
intake of vitamin E? Explain.
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4. Which of the four fat-soluble vitamins discussed in this chapter play a role in bone health? List foods that are
good sources of each.
5. What cautions would you give Joan regarding her intake of high-vitamin K foods that pertain to her use of a
blood-thinning medication?
6. Using information in Highlight 11, explain some simple dietary strategies that could improve Joan’s intake of
antioxidants. Explain which supplements, if any, may be helpful as well.
Answer Key
1. Decreased ability of the skin, liver, and kidneys to make and activate vitamin D with advancing age; low intake
of vitamin D-fortified milk; limited sun exposure.
Suggested Classroom Activities
Like the water-soluble vitamins, the fat-soluble vitamins are endlessly fascinating. Outside reading from the recent
literature can give the class the latest on many interesting topics. The advertising emphasis on antioxidants to sell
supplements is a hot topic that will likely generate student interest. Several vitamin activities have been presented in
Chapter 10 of this manual that can also be used in the study of this chapter. Please see Classroom Activities 10-1
through 10-6.
Classroom Activity 11-1: Vitamin K and Coumadin Therapy (Meal Comparison)
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Key concepts: Vitamin K food sources; food-drug interactions Class size: Any
Instructions: Read the case scenario to students, present the two dinner meal plans to them, and use the discussion
questions to prompt them to consider the vitamin K content of the plans.
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Contributed by Carrie King
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Discussion questions:
1. What is the DRI for vitamin K for men and women? (Hint: Use the chart inside the front cover of your
textbook.)
2. Which foods provide the most vitamin K in the two meal plans?
3. What could be changed to make the meal plan more consistent in vitamin K between both of the two meal
plans?
Answer key:
1. Men: 120 micrograms/day; women: 90 micrograms/day
Nutrient composition of meals for instructor reference:
Cal
Vit K
Dinner #2 Item
Cal
Vit K
262
1.8
Grilled chicken breast, 3 oz
230
3.2
120
12.6
Wild rice, 1 cup
166
0.8
27
110
Spinach, steamed, ½ cup
20
444
74
2.0
Biscuit, 1 item
150
2.3
55
30
Peach, fresh, 1 medium
58
3.9
102
0.2
1% milk, 1 cup
102
0.2
640
156.6
Totals
726
454.4
Key: Cal = kcalories, Vit K = vitamin K (micrograms)
Classroom Activity 11-2: Antioxidant Research Analysis
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Key concept: Antioxidants in heart disease/cancer Class size: Small to medium
Instructions: Ask each student to select a peer-reviewed research article on the benefits of antioxidant therapy in the
prevention or treatment of heart disease or cancer. The student may select an article that points to the benefits of
acquiring their antioxidant therapy from food, supplements, or a combination thereof.
For the article, the student should write a report outlining the overall purpose of the article, the research question,
study audience, methods, results, and conclusions in a brief form. Then the student should critique the article,
discussing their thoughts on the study as a whole and the conclusions of the authors. Did the student think that the
study led to valid conclusions? Were there any differences between researchers that studied antioxidant therapy from
food as opposed to those that studied antioxidant supplementation or in combination? Have the students discuss their
findings in class.
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How To “Try It” Activities Answer Key
How to Convert International Units (IU) to Weight Measurements
1200 µg vitamin A (retinol), 15 µg vitamin D (cholecalciferol), 8.04 mg vitamin E (alpha-tocopherol)
Study Card 11 Answer Key
1. Vitamin precursors are compounds that can be converted to an active form of a vitamin within the body. Many
Critical Thinking Questions
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1. Explain how fat-soluble vitamins contribute to the overall health of the body.
2. What is the major idea behind fortification of food products with vitamin D in the United States?
3. An individual is placed on antibiotic therapy. For which vitamin deficiency is he/she at greatest risk? Why
might this occur? How can this be prevented?
4. Discuss the three associated bone diseases for which vitamin D metabolism is of clinical relevance.
5. Why is vitamin K given to newborns upon delivery? What happens if the newborn does not get the injection?
6. An individual consumes a large amount of vitamin A food sources and his/her skin turns yellow. Is this
clinically significant? Why or Why not?
Answer Key
1. Each of the fat-soluble vitamins plays a role in helping maintain the overall health of the body. Vitamin A plays
a significant role in immune function (as an antioxidant), vision, skin integrity, and growth and development.
Vitamin D plays a significant role in bone health and endocrine function. Adequate endogenous vitamin D
formation requires adequate renal function and sunlight. Vitamin E plays a significant role in immune function,
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2. Food products are fortified with vitamin D in the U.S. in order to provide a stable, consistent source of the
vitamin for the general population. There are few natural food sources, and not everyone can maintain adequate
3. An individual who is placed on antibiotic therapy is at risk to develop a vitamin K deficiency. This occurs
4. Rickets is a disease state associated with a clinical vitamin D deficiency in children. Structural integrity of the
bones is diminished, leading to characteristic bowed legs and beaded ribs. The occurrence of a clinical vitamin
5. A vitamin K injection is recommended for all newborns in order to provide needed vitamin K until its intestinal
production by bacteria begins. Since the infant is born with a sterile gut, there are no bacteria present to start
6. There are several chemical compounds that have vitamin A activity, the most common of which are
carotenoids, of which beta-carotene is most easily recognized. If an individual consumes a large amount of
IM Worksheet Answer Key
Worksheet 11-1: Fat-Soluble Vitamins’ Equivalent Measurements
1. Twice as much.
Worksheet 11-2: Chapter 11 Crossword Puzzle
3. Fat
6. beta-carotene
9. alpha-tocopherol
12. oxidative stress
2. b
3. a
4. a, b
5. b
6. a, b, d
Worksheet 11-3: Fat-Soluble Vitamin Review (Internet Exercise)
1. a. Toxicity can lead to increased pressure in the skull, b. Prevents damage to cell membranes, c. Deficiency
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Worksheet 11-1: Fat-Soluble Vitamins’ Equivalent Measurements
Vitamin A = 1 RAE (retinal activity equivalent) = 1 microgram of retinol = 3.33 IU (International Units)
= 12 micrograms of dietary beta-carotene = 2 micrograms of beta-carotene supplements
= 24 micrograms of other vitamin A precursor carotenoids
There is so much discussion and confusion related to the measurements of fat-soluble vitamins that it becomes
difficult for one to explain what the measurements actually indicate. In the table listed above are the common
equivalent measurements for each of the fat-soluble vitamins. Consider these equivalent measurements when
answering the questions below.
1. If you obtained your daily vitamin A intake from a precursor carotenoid source other than beta-carotene, how
much would you have to consume as compared with obtaining your daily vitamin A from a dietary source of
beta-carotene?
5. Select one food item that you take in on a daily basis and then determine the relative equivalent measurements
for the fat-soluble vitamins indicated above. Note whether or not the food item that you have selected meets the
recommended dietary intakes for that nutrient.
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Worksheet 11-2: Chapter 11 Crossword Puzzle
1
2
3
4
5
6
7
8
9
10
11
12
Across:
Down:
5. Vitamin A toxicity is usually associated with
consuming _____.
9. The only form of vitamin E that is active in the
human body
12. Antioxidants help to protect the body against _____.
and absorption.
4. Primary source of vitamin E in the diet
8. Vitamin D-deficiency disease
11. Almost all of the fat-soluble vitamins have a role in
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Worksheet 11-3: Fat-Soluble Vitamin Review (Internet Exercise)
1. Match the vitamin with its pertinent information.
a. A
b. E
c. D
d. K
_____ Deficiency state can cause excessive bleeding
_____ Deficiency state in adults is called osteomalacia
_____ Prevents damage to cell membranes
_____ Toxicity can lead to increased pressure in the skull
2. One retinol activity equivalent is equal to 10 micrograms of beta-carotene.
3. Symptoms of vitamin A toxicity include dizziness and blurred vision.
4. Which of the following are ways that we obtain vitamin D?
5. The active form of vitamin K is alpha-tocopherol.
6. Which of the following individuals is at risk for deficiency of vitamin K?
a. A person who is taking antibiotics for an infection
b. A person who has been having repeated bouts of diarrhea
c. A person who is eating large amounts of cauliflower
d. A person who is receiving anticoagulant therapy
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Worksheet 11-4: Antioxidants
Consider the questions listed below and perform the following search methods in order to locate information to help
answer them: traditional library search, database search, textbook search, and web-based search engine search. See
how the information you have gathered differs in both its amount and the quality of information.
1. Which vitamins are considered to have antioxidant properties?
2. Why does oxygen pose a threat to cell structures?
6. Is there clinical evidence that antioxidants improve health outcomes?
7. Do foods differ in their antioxidant composition?