HNE25306
Problem set 5: Basic Principles of Micronutrients and Minerals & Trace Elements
Instructor: Sander Kersten
Basic principles of micronutrients
1. Why do fat soluble vitamins tend to be more toxic than water soluble vitamins?
2. Supplementation of human populations with water-soluble vitamins requires a
completely different strategy compared to supplementation with fat soluble vitamins.
Why?
3. There has been lot of controversy about the potential benefits of vitamin
supplementation on risk for chronic diseases, including cancer and cardiovascular
disease. Imagine a case-control study that showed that lung cancer patients were much
more inclined to take vitamin supplements compared to subjects that do not have lung
cancer, suggesting that supplement use promotes lung cancer.
a) What is a case-control study?
b) What are your reservations about this type of research design and to what extent could
they have led to the specific research outcome?
c) What subjects should ideally serve as control group?
d) What type of research design yields much more reliable scientific conclusions about
the potential health risks/benefits of supplement use?
e) Personally, I find the following press report to be out of sync with the conclusion of
the original research paper.
f) Taking into account the results of a recent trial which showed that use of a daily
multivitamin supplement at low dose caused a modest reduction in total cancer incidence,
what general conclusion about vitamin supplements do you reach?
4. The function of one particular dietary mineral is intimately tied to the function of a
particular vitamin. Explain.
5. Why do plant foods generally have a lower bioavailability of minerals than foods of
animal origin?
6.
a) Vitamins can be separated into two main classes. Describe these classes and mention
three important differences between these two classes of vitamins.
b) Recommendations for energy and micronutrients are set differently. Explain how and
why.
Minerals and trace elements
1. What is the approximate water content of the human body expressed as a percentage of
total bodyweight?
, 2. By approximately how much does our daily sodium intake exceed the daily
requirement?
3. The concentration of calcium inside the cells is extremely low. Influx of calcium into
the cell is used to trigger several processes. Can you give some examples?
4. What is the difference between osteomalacia and osteoporosis?
5. Name a food that is among the most concentrated dietary sources of calcium when
expressed per gram of food?
6. Why are plasma levels of calcium relatively poor indicators of calcium status. Explain.
7. People are advised to consume fish regularly because of its high content of n-3 fatty
acids. Why shouldn’t we consume fish too often?
8. The long-term exposure status to certain dietary minerals can be determined by
analyzing small, easily removable parts of the body. What part am I referring to ?
Does it help if I say that this type of analysis is also used in forensic medicine and
toxicology.
9. A genetic disease that is relatively common in Northern Europe is characterized by
elevated absorption of iron and as a result excessive storage of iron in the body. The
excess iron can be removed by periodic phlebotomy (blood donations). If untreated,
affected patients may suffer from liver damage and heart failure. What is the name of this
disease?
10. Why, despite a huge daily iron requirement to accommodate hemoglobin synthesis,
do we only need to absorb a relatively small amount of dietary iron?
11. (This is a former exam question !)
a. Explain the main role of iron in the body.
b. Why is it difficult to give an estimate of the efficiency of absorption of dietary iron?
Why is this true even for individual foods ?
c. Describe and explain the symptoms of (chronic) iron-deficiency.
12. Is it better to use sea salt compared to normal table salt?
13. Not everybody agrees that salt reduction will provide any health benefits. See:
http://www.saltinstitute.org/health/overview/
However, what disqualifies these people from entering the discussion?
14. The pathological consequences of iodine deficiency can be traced back to a single
defect. Explain.
15. (this is a former exam question)
Problem set 5: Basic Principles of Micronutrients and Minerals & Trace Elements
Instructor: Sander Kersten
Basic principles of micronutrients
1. Why do fat soluble vitamins tend to be more toxic than water soluble vitamins?
2. Supplementation of human populations with water-soluble vitamins requires a
completely different strategy compared to supplementation with fat soluble vitamins.
Why?
3. There has been lot of controversy about the potential benefits of vitamin
supplementation on risk for chronic diseases, including cancer and cardiovascular
disease. Imagine a case-control study that showed that lung cancer patients were much
more inclined to take vitamin supplements compared to subjects that do not have lung
cancer, suggesting that supplement use promotes lung cancer.
a) What is a case-control study?
b) What are your reservations about this type of research design and to what extent could
they have led to the specific research outcome?
c) What subjects should ideally serve as control group?
d) What type of research design yields much more reliable scientific conclusions about
the potential health risks/benefits of supplement use?
e) Personally, I find the following press report to be out of sync with the conclusion of
the original research paper.
f) Taking into account the results of a recent trial which showed that use of a daily
multivitamin supplement at low dose caused a modest reduction in total cancer incidence,
what general conclusion about vitamin supplements do you reach?
4. The function of one particular dietary mineral is intimately tied to the function of a
particular vitamin. Explain.
5. Why do plant foods generally have a lower bioavailability of minerals than foods of
animal origin?
6.
a) Vitamins can be separated into two main classes. Describe these classes and mention
three important differences between these two classes of vitamins.
b) Recommendations for energy and micronutrients are set differently. Explain how and
why.
Minerals and trace elements
1. What is the approximate water content of the human body expressed as a percentage of
total bodyweight?
, 2. By approximately how much does our daily sodium intake exceed the daily
requirement?
3. The concentration of calcium inside the cells is extremely low. Influx of calcium into
the cell is used to trigger several processes. Can you give some examples?
4. What is the difference between osteomalacia and osteoporosis?
5. Name a food that is among the most concentrated dietary sources of calcium when
expressed per gram of food?
6. Why are plasma levels of calcium relatively poor indicators of calcium status. Explain.
7. People are advised to consume fish regularly because of its high content of n-3 fatty
acids. Why shouldn’t we consume fish too often?
8. The long-term exposure status to certain dietary minerals can be determined by
analyzing small, easily removable parts of the body. What part am I referring to ?
Does it help if I say that this type of analysis is also used in forensic medicine and
toxicology.
9. A genetic disease that is relatively common in Northern Europe is characterized by
elevated absorption of iron and as a result excessive storage of iron in the body. The
excess iron can be removed by periodic phlebotomy (blood donations). If untreated,
affected patients may suffer from liver damage and heart failure. What is the name of this
disease?
10. Why, despite a huge daily iron requirement to accommodate hemoglobin synthesis,
do we only need to absorb a relatively small amount of dietary iron?
11. (This is a former exam question !)
a. Explain the main role of iron in the body.
b. Why is it difficult to give an estimate of the efficiency of absorption of dietary iron?
Why is this true even for individual foods ?
c. Describe and explain the symptoms of (chronic) iron-deficiency.
12. Is it better to use sea salt compared to normal table salt?
13. Not everybody agrees that salt reduction will provide any health benefits. See:
http://www.saltinstitute.org/health/overview/
However, what disqualifies these people from entering the discussion?
14. The pathological consequences of iodine deficiency can be traced back to a single
defect. Explain.
15. (this is a former exam question)
