Download option a

Human Nutrition and Health
Option A
Topics covered
• A1: Components of the human diet
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Nutrients needed in the diet
Deficiency diseases
Fatty Acids
Vitamins and minerals
Fibre
• A2: Energy in Human Diets
– Sources of energy
– Identifying eating disorders – obesity and anorexia
2
Topics covered
• A3: Special issues in Human nutrition
– Breast-feeding
– Diabetes
– Vegetarians / Vegans
– Low cholesterol diets
– Food miles
3
How to use this PowerPoint
• The majority of this PowerPoint is aimed for you to
complete the study on your own. USE YOUR TEXT BOOK!
• You will be making a portfolio of all the information you
have learnt.
• Instructions that are in red refer to what I expect to see in
your portfolio. Any extra information is fantastic!
• DON’T FORGET TO REFERENCE ANY WEBSITES OR
BOOKS YOU USE IN A BIBLIOGRAPHY!!!
4
Components of the human diet
A1
Nutrients
• Nutrients are chemicals found in food that the
body needs to function.
• Given the right raw materials, the human
body can manufacture many useful chemicals
from breaking down and reassembling other
chemicals.
• Essential nutrients are ones that the body
cannot manufacture. Therefore we have to
eat them regularly.
Questions
Research and answer these questions in full sentences:
• What are nutrients?
• What are essential nutrients?
• Give 2 examples of essential amino acids
• Give 2 examples of essential fatty acids
• Give 2 examples of essential minerals
• Give 2 examples of essential Vitamins
• Why is water so important in the diet?
• What are non-essential amino acids? Give 2 examples.
Malnutrition
• There are 3 main kinds of malnutrition:
• Not enough food
• Too much food
• Not the right type of food
• All can lead to health problems.
Kwashiorkor
• These children are
suffering from
Kwashiorkor – protein
deficiency.
• Explain why they have
swollen abdomens.
PKU
Research and answer the following questions in
detail and in full sentences:
1. What causes PKU?
2. What enzyme are sufferers of PKU unable to
produce? What are the consequences of this
(explain in full)?
3. How can PKU be controlled by early diagnosis?
4. How can PKU be controlled by diet?
Fatty Acids
Copy and complete this table to outline the differences between
the different structures of fatty acids:
Name
Saturated fatty
acids
Cis unsaturated
fatty acids
Trans unsaturated
fatty acids
Mono unsaturated
fatty acids
Poly unsaturated
fatty acids
Diagram of
structure
Description of Foods that
structure
contain them
Health
implications
Fat diets across the world:
Introduction
• Read the information on this website and answer the
following questions:
• What are the benefits of eating eicosapentaenoic acid
(EPA) and docosahexaenoic acid (DHA) from fish and
fish oils?
• What is hydrogenation? Why is it done?
• HDL stands for High Density Lipoproteins (often called
“good cholesterol). LDL stands for Low Density
Lipoproteins (“bad cholesterol). Using this
information, explain why hydrogenation is thought to
be bad for health.
Fat diets across the world:
Mediterranean diets
• How does eating a diet rich in olive oil help
reduce the levels of Coronary Heart Disease
(CHD) in Mediterranean populations?
• What else is in the Mediterranean diet that
might help reduce CHD? How does the article
say they protect cells from damage?
• What are the other benefits of MUFA?
Fat diets across the world:
Eskimo and Japanese diets
• Give 3 examples of fatty, cold-water fish. What
useful substances do they contain?
• What health benefits might this account for?
• How can you tell that it is not just Japanese
genetics that gives them these health benefits?
• What study led experts in the US to define a
weekly consumption of 1-2 servings of fish as
consistent with good health?
Fat diets across the world:
Analysing the studies
• Summarise the other dietary components and
non-dietary factors that contribute to the
health and well-being of the Mediterranean
and Japanese ethnic groups.
• Do you think there is enough evidence to
support the claims made by the studies in the
Mediterranean and Japan? Look at this
website before you answer!
Vitamins and Minerals
• Distinguish between the chemical structure of
Vitamins and Minerals – use Page 194 of your
text book.
• What does RDI stand for?
• What is the older method for calculating RDI?
• What is the more modern method?
Vitamin C
• Read this website and your text book P 194 – 5.
• What is the Vitamin C deficiency disease? Discuss how to
cure it.
• What is the difference between RDI, RDA and DRI?
• How much Vitamin C is needed to “saturate” the body?
What happens to any excess?
• The RDA of Vitamin C has changed over the years (see fig
1208 on p 195 of your text book). Why?
• What are the benefits and dangers / adverse effects of
taking more than the RDI of Vitamin C? (Give details)
• Read the TOK section on P 195 of your text book. Give your
response to the question asked.
Vitamin D
Property
Answer
Soluble in
Needed for
Where it is made
What else is needed to make it
Foods that contain it
Deficiency disease in children
Name:
Description:
Deficiency diseases in adults
Names:
Description:
Issues surrounding getting
sufficient Vitamin D to avoid
deficiency disease
IB question
• Answer this past paper question with regard
to sunlight and Vitamin D deficiency:
• Suggest how environmental conditions cause
malnutrition [2]
Dietary supplements
•
1.
2.
3.
4.
5.
Iodine is an essential mineral in the diet. In many parts of
the world children show symptoms of iodine deficiency.
Find out the answers to these questions:
How is iodine used in the human body?
What are the symptoms of iodine deficiency?
What would be the benefits of dietary supplementation
with iodine?
Would it be feasible to develop a world wide programme of
dietary iodine supplementation?
Are there other mineral deficiencies that are widespread
causes of malnutrition?
IB Question
• Discuss the importance of fibre in the diet.
[3]
Energy in Human diets
A2
IB Question
This question is taken from the specimen paper for 2008!
You don’t get more up to date than this! Use P 197 in your
text book to answer it.
Energy and Ethnicity
• “Staple” foods are eaten in bulk to provide
energy.
• Different cultures have different staple foods
due to availability, cultural preferences and
traditions.
• Make a poster showing different staple foods
from around the world and the cultures that
eat them.
Health consequences of diet
• Rearrange this table so the information it shows is
correct:
Diet contains lots
of…
Health consequences
Fat
Makes you feel full faster and for longer. Can also be
used for energy if necessary although this does
require the kidneys to excrete more urea which could
damage them.
Protein
Provides lots of energy which is beneficial before a
big sporting event. Excess can be turned into fat
causing obesity.
Carbohydrate
Contains lots of energy which could cause obesity.
Also linked to cancer of the colon.
Appetite control
• Copy and complete the flow chart on the next
slide to explain how appetite is controlled in
the brain
• Add annotations to explain what happens
when parts of this system stop working.
Start eating
Hormones from ___________
and __________
travel via the blood to the…
The ______ _______ _______
in the ________ in the brain
detects that no more food
needs to be eaten.
Stop eating
_______ Gene creates
leptin in _______ tissue
__________ tissue
sends ________ to the
brain to tell it________
___________________
___________________
Body Mass Index
• Do a survey of your friends and family and
work out their BMI. (Ask permission first!).
• Present this in your portfolio showing the
calculations you did (including the equation).
• Classify your subjects as underweight, normal
weight, overweight or obese using the BMI
categories in the text book.
• Add the people on the next page into your
survey:
BMI
Name
Mass (kg)
Height (m)
Sarah
70
1.4
John
60
1.85
Nguyen
67
1.5
Anh
63
1.7
Why is obesity increasing?
• Suggest and
explain 4 reasons
for the data
shown in this
table.
• Use Syllabus
statement A.2.7 to
guide you.
Gender
% obese
1966 - 70
% obese
1988 - 91
Boys
5
13
Girls
5
9
Anorexia nervosa
• Anorexia nervosa is a disease with psychological
causes. Someone who has anorexia becomes
chronically underweight because they do not eat
enough food even if plenty is available.
• What are the physiological consequences (effects on
the body) of anorexia in relation to:
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Muscle mass?
Hair growth?
Blood pressure?
Fertility?
Menstruation?
Dental health?
Anorexia nervosa
• What are the consequences for the family and
friends of someone who develops anorexia?
• Read this article: http://www.mediaawareness.ca/english/issues/stereotyping/women_a
nd_girls/women_beauty.cfm
– What are your views on magazines using young ultra thin
models for advertising?
– Is it acceptable?
– What could the consequences be?
– How can we build a society where healthy body shape is
valued?
Special issues in human nutrition
A3
Breast feeding
• Design a leaflet to persuade new mothers to
breastfeed their babies rather than use
formula (artificial) milk.
• It should include:
– The difference between breast and artificial milk
– The benefits of breast feeding
– Reassurance that breast feeding in public is
acceptable
• This should be a biased piece of writing!
Breastfeeding 2
• Read the article on this website:
• http://www.breastfeeding.com/advocacy/adv
ocacy_boycott.html
• Explain as fully as you can the reasons why
someone may boycott buying Nestle products.
• Are you convinced to boycott Nestle??
Breast feeding 3
• Remember – breastfeeding doesn’t work out
for every mother!
• Read this article for a (slightly) less biased
view!)
– http://kidshealth.org/parent/growth/feeding/bre
ast_bottle_feeding.html
Diabetes
• The cause and treatment of Diabetes is covered in
the core syllabus in sections 6.5.11 and 6.5.12.
• Year 13 – you should have already covered this!
• Year 12 – you may like to read P 112 – 113 in your
text book to get an overview.
• Briefly outline the difference between Type I and
Type II diabetes (you do not have to give any details
of the cause or treatment).
Type II Diabetes
•
1.
2.
3.
4.
Read P 201 in your text book and answer
these questions:
What has happened to the incidence of Type
II diabetes in America since 1997?
What are the causes for this?
What are the symptoms of Type II diabetes?
What dietary advice is given to people with
Type II diabetes?
To Meat or not to Meat
• Explain why some people prefer not to eat
animals or animal products.
Cholesterol and heart disease
•
1.
2.
3.
Read P 202 in your book
What is cholesterol?
What is cholesterol needed for?
Explain how cholesterol can cause a heart attack or
stroke.
4. Explain the change in thinking about the
relationship between dietary cholesterol and
serum (blood) cholesterol.
5. How is cholesterol transported in the blood?
6. Complete the diagrams on the next two slides.
Transport of cholesterol
Cholestero
l in
blood
•
•
•
•
•
•
Transported by
__________ (good
cholesterol)
Liver
Cholesterol
broken
down
Can be increased by:
E__________
Not s__________
W________ loss
Omega 3, _________________________
A diet containing a lot of _________ and limited
amounts of _______.
• Moderate use of a__________??? (not proven!)
Transport of cholesterol
Cholestero
l in
blood
Cholesterol
can cause
plaques
Transported by
__________ (bad
cholesterol)
•
•
•
•
•
•
Liver
Can be increased by:
No E__________
S__________
Putting on w________
trans _________________
A diet containing too little _________ and
lots of _______.
Food miles
• Read the article on this website:
http://www.bbc.co.uk/food/food_matters/foo
dmiles.shtml
• Discuss the concept of food miles and the
reasons for consumers choosing foods to
minimize food miles
Checklist for your portfolio
1.
2.
3.
4.
5.
Questions on nutrients from slide 7
Explanation of Kwashiorkor from slide 9
Research and questions from slide 10 on PKU
Completed table on fatty acids from slide 11
Questions from slides 12 – 15 on fat diets across
the world (using the website)
6. Questions on vitamins and minerals from slide 16
7. Questions on Vitamin C from slide 17 using website
8. Completed table on Vitamin D from slide 18 and
answer the past paper question on slide 19.
Checklist for your portfolio
9. Answer the questions on iodine supplementation
from slide 20
10. Answer the IB question on fibre from slide 21
11. Answer the IB question on energy content of food
from slide 23
12. Make a poster to show different staple diets (slide
24)
13. Rearrange the table from slide 25
14. Copy and complete the flow chart from slide 27
adding annotations.
15. Write up your survey and results showing your BMI
calculations.
Checklist for your portfolio
16. Answer the questions on the causes of obesity
from slide 30
17. Research anorexia nervosa and answer the
questions on slides 31 – 32.
18. Design the leaflet from slide 34.
19. Explain why people boycott Nestle products (slide
35).
20. OUTLINE the difference between Type I and Type II
diabetes (one or two sentences!)
21. Answer the questions on slide 38 on diabetes
22. Answer the question on slide 39
Checklist for your portfolio
23. Answer the questions on cholesterol on slide 40
and fill in the diagrams on slides 41 – 42.
24. Read the website article from slide 43 and answer
the question.
25. Check through your work and make sure you have
added all your references into your bibliography.
26. RELAX!!
27. Due in on February 3rd (Year 12)