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4. Suppose one of your colleagues came up to you and asked what you were majoring in. You told them that you
were majoring in nutrition and dietetics and were really stressed about your upcoming biochemistry test! All of
a sudden your friend responded, “I thought you said you were majoring in nutrition and dietetics… are you
planning on going to med school or something? Why would you need chemistry when you are in a cooking
major?” How might you best respond to your friend to help them understand how important biochemistry is to
the field of nutrition and dietetics?
Answer: Taking a very different approach, this is one of my favorite questions to ask my doctoral students. Of
course, my question is, explain the role of vitamins in all the biochemical pathways! Students, especially in the
undergraduate years, don’t always fully comprehend the importance of the role of their biochemistry classes in
their studies and here is where they can really comprehend its true importance.
5. Differentiate between water– and fat-soluble vitamins and discuss how a diet that is low in fat might impact
vitamin absorption.
Answer: Water-soluble vitamins are vitamins that can be absorbed in an aqueous environment. In general, they
are not stored in the body; however, vitamin B6 appears to have some ability to be stored in the muscle. There is
6. There is much debate regarding the need for consumers to take vitamin and/or mineral supplements. As a
nutrition professional, how would you advise a client (female who is 60 y/o and has no medical history, has no
current medical problems, and takes no medications) that believes in and therefore insists on taking large doses
of vitamin and mineral supplements to prevent disease?
Answer: A consumer’s desire to take a vitamin/mineral supplement is driven by many factors, many of which
have little scientific evidence for validation. For the nutrition student, it is important to keep in mind that
nutrition as a science is comparatively young, in relation to many of the other basic sciences, and in this regard,
Dietary assessment is required as well as physical and biochemical assessment to acquire information on any
physical illnesses or past histories. Medical background and history should be acquired as well. The assumption
is that the client is asymptomatic and that this is simply a desire without physical rationale; therefore, the RD
must deal with the psychological/mental concerns and work to have the client fill vitamin and mineral needs
through diet.
The best approach here is to ask about the length of time this individual has been taking the supplements, and in
what doses, and to have a very clear understanding of her diet and all medical information as well as the above
information.
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were changing. All things to be explored. That being said, because she is in good health, is not taking
medications that would interact with the supplements, and has no medical history, this is a client that would
benefit from nutrition education as to where the various vitamin and minerals can be found in foods and how
IM Worksheet Answer Key
Worksheet 10-1 – Answers will vary.
Worksheet 10-2: Bioavailability Concept
Situations
↓ Bioavailability
Minimal effect on
bioavailability
↑ Bioavailability
Par boiling
Microwaving
Processed foods
Fortified foods
Medical condition of individual
Amount of food eaten
Quality of food eaten
Nutritional status of individual
Food composition of a meal
Worksheets 10-3 and 10-4 – Answers will vary.
Worksheet 10-5: title
Worksheet 10-6: Water-Soluble Vitamin Review (Internet Exercise)
Canadian Information9
10.1 Canadian Recommendations for Intake of Water-Soluble Vitamins for Healthy People
Eating Well with Canada’s Food Guide
• Eat at least one dark green and one orange vegetable each day.
• Have vegetables and fruit more often than juice.
10.2 Vitamin Content in Canadian Foods
Differences in the vitamin content of foods sold in Canada, compared to the values provided in the textbook for
foods sold in the U.S., are due to differences in national regulations for food fortification. These were discussed in
Section 2.3, Food Fortification in Canada, of the Canadian Information section in this Instructor’s Manual. A review
Students should be aware that folic acid fortification in Canada was a public health initiative initiated by the
Government of Canada in 1998 (after they were born). Fortification is required at a minimum level of 0.15 mg folic
acid per 100 grams of white flours13 and cornmeal,14 and 0.20 mg folic acid per 100 grams of enriched pasta.15 These
levels are similar to folic acid fortification in the United States, which is set at 0.14 mg folic acid per 100 grams of
cereal grain product. In Canada, this public health initiative has produced a significant decline in the incidence of
neural tube birth defects.16 The mandatory enrichment of flour, white flour, enriched flour, and enriched white flour
10.3 Reference Daily Values for Water-Soluble Vitamins
On food labels, the % Daily Value information provided for the water-soluble vitamins is based on Canadian
reference Daily Values, otherwise known as the Recommended Daily Intake (RDI). RDI are legislated in current
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nutrition labelling requirements found in the Food and Drug Regulations.17 Canadian reference Daily Values for all
water-soluble vitamins, except vitamin C, are different from those listed in the textbook. Table 10.1 presents a
comparison between reference Daily Values used in Canada and the United States.
Table 10.1 Reference Daily Values for Water-Soluble Vitamins Used in Canada for Persons 2 Years and
Older17 Compared to Reference Daily Values Used in the United States for Persons 4 Years and Older18
Water-Soluble Vitamin
American Daily Value
Vitamin C
60 mg
Highlight 10: Vitamin and Mineral Supplements
Regulation of Vitamin and Mineral Supplements in Canada
In Canada, non-therapeutic vitamin and mineral supplements are considered natural health products (not foods, not
drugs) and since 2004 have been regulated by the Natural Health Products Regulations,19 found in Canada’s Food
and Drugs Act.20 Natural Health Products must be safe for consideration as over-the-counter products, be available
If you are teaching Canadian students who live near the border with the United States, an interesting activity for
students is to compare the cost and the content of vitamin and mineral supplements from each country.
17 Justice Canada. Food and Drug Regulations, Section D.01.013, Table 1: Recommended Daily Intake. Available
Thiamin (vitamin B1)*
1.3 mg
1.5 mg
Riboflavin (vitamin B2)*
1.6 mg
1.7 mg
20 mg
1.8 mg
2.0 mg
Folacin or folate*
220 µg
400 µg
2 µg
6.0 µg
Pantothenic acid*
7 mg
10 mg
30 µg
300 µg
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Worksheet 10-1: Vitamin History in Clinical Research
1. Perform a web-based search in Pub Med or Science Direct for the following: thiamin vitamin history, niacin
vitamin history, and ascorbic acid vitamin history.
2. How many articles did you find on each vitamin?
Consider the following questions using a ROUND table approach:
• In terms of scientific evidence do we have a long history of information with respect to thiamin, niacin or
ascorbic acid?
• How have the discoveries of these vitamins led to influences in public health practices throughout the world?
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Worksheet 10-2: Bioavailability Concept
For the following situations, indicate whether or not the bioavailability of the nutrient content
would be affected related to vitamin content. (Choose all that apply.)
Situations
↓ Bioavailability
Minimal effect on
bioavailability
↑ Bioavailability
Par boiling
Medical condition of
individual
Amount of food eaten
Quality of food eaten
Nutritional status of
individual
Food composition of a meal
Processed foods
Fortified foods
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Worksheet 10-3: Vitamin/Mineral Supplement Evaluation
Complete the supplement evaluation form about a selected supplement.
1. What is the name of the supplement?
4. Are most vitamins and minerals present at or near 100% of the adult DRI? Exceptions include biotin, calcium,
magnesium, and phosphorus, which are rarely found in amounts near 100% of the DRI. List any vitamins or
minerals that are present in low amounts or dangerously high amounts.
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Worksheet 10-4: Vitamins in Your Diet
A diet that offers a variety of foods from each group, prepared with reasonable care, serves up ample
vitamins. The cereal and bread group delivers thiamin, riboflavin, niacin, and folate. The fruit and
vegetable groups excel in folate, vitamin C, vitamin A, and vitamin K. The meat and beans group serves
thiamin, niacin, vitamin B6, and vitamin B12. The milk group stands out for riboflavin, vitamin B12,
vitamin A, and vitamin D. Even the oils group with its vegetable oils provides vitamin E. Determine
whether these food choices are typical of your diet.
Food choices
Frequency per week
Citrus fruits
Dark green, leafy vegetables
1. Do you eat dark green, leafy or deep yellow vegetables daily?
2. Do you drink vitamin A- and D-fortified milk regularly?
Deep yellow or orange fruits or vegetables
Legumes
Milk and milk products
Vegetable oils
Whole- or enriched-grain products
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Worksheet 10-5: Chapter 10 Crossword Puzzle
Across:
Down:
2. a test result indicating that a condition is present
when in fact it is not
5. a symptom of vitamin B deficiencies; an
inflammation of the tongue
1. the niacin-deficiency disease causing dermatitis
2. a test result indicating that a condition is not present
when in fact it is present
3. a temporary burning, tingling, and itching sensation
1 4
3
2
6
5
7
8
9
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Worksheet 10-6: Water-Soluble Vitamin Review (Internet Exercise)
1. Which of the B vitamins is most sensitive to light?
2. The ingestion of water-soluble vitamins does not cause any side effects or adverse reactions due to
3. The stability of some water-soluble vitamins is affected by alkaline solutions.
a. True
b. False
4. Which water-soluble vitamin helps participate in protein metabolism? Select ALL that apply.
5. Pernicious anemia occurs as a result of thiamin deficiency.
a. True
b. False
6. Match the vitamin with its corresponding pertinent information.
a. Biotin
b. Folic acid
c. Ascorbic acid
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Handout 10-1: RDA/AI and UL for Vitamins Compared