1. Dietary fibre and water
(Extension)

2. Learning objectives
To know the functions and sources of dietary fibre.
To understand the health benefits of dietary fibre.
To know the functions and sources of water.
To understand the principles of fluid balance.

3. Dietary fibre
Dietary fibre is a diverse group of carbohydrate found almost exclusively in plants, including non-starch polysaccharides such as cellulose and pectin, and lignin.
Unlike other types of carbohydrate, these are not absorbed in the small intestine to provide energy, although it is digested in the large bowel by bacteria, providing 2kcal/8kJ per gram on average.

4. Sources of dietary fibre
Components of dietary fibre are found in different proportions in food, therefore it is important to eat a variety of fibre-containing foods. 
Dietary fibre is found in:
wholegrain cereals and cereal products;
beans;
lentils;
fruit and vegetables;
nuts and seeds.

5. Fibre in the diet
Dietary fibre helps to:
reduce your risk of heart disease, diabetes and some cancers;
help weight control;
bulk up stools and make waste move through the digestive tract more quickly;
prevent constipation;
improve gut health.

6. How much fibre do we need?
Most people do not eat enough dietary fibre.
The recommended average intake for dietary fibre is 30g per day for adults. Children need proportionately less.
Current adult intake is around 19g per day on average, less that the recommended levels for a 5 year old.

7. Fibre on food labels
European regulations on nutrition and health claims state that a product claiming to be a ‘source of’ fibre should contain at least 3g of dietary fibre per 100g, and for a product which contains at least 6g of dietary fibre per 100g, this can be labelled as ‘high in’ fibre.

8. Can you think of ways to increase fibre in your diet?

9. Can you think of ways to increase fibre in your diet?
Choose a high fibre breakfast cereal e.g. bran flakes, or porridge
Go for wholemeal or granary breads instead of white bread
Choose wholegrains like wholewheat pasta, bulgur wheat or brown rice
Go for potatoes with skins e.g. baked potato or boiled new potatoes
For snacks try fruit, vegetable sticks, rye crackers, oatcakes, unsalted nuts or seeds
Include plenty of vegetables with meals – either as a side dish or added to sauces, stews or curries
Add pulses like beans, lentils or chickpeas to stews, curries and salads
Have some fresh or dried fruit, or fruit canned in natural juice for dessert.

10. Water
Water is essential for life. It is the major component of body fluids and helps to maintain normal physical and cognitive functions, as well as the normal regulation of the body’s temperature. Water also helps to get rid of waste substances in the body.
The body is nearly two-thirds water, so it is important to consume enough fluid to stay hydrated. If we do not consume enough water, we become dehydrated.

11. Water
Our bodies lose water all the time, when we go to the toilet, from sweat and also through respiration. We need to replace this water by drinking regularly to prevent dehydration.
Even mild dehydration can lead to headaches, irritability and loss of concentration.
Did you know?
Humans can survive for a few weeks without food, but they cannot go without fluids for more than two to three days.

12. Sources of water
Water is provided by food such as soups, yogurts, fruit and vegetables, as well as drinks such as milk and juice.
Water is a good choice of drink because it hydrates without the provision of energy.

13. How much water do we need?
The amount of water and other fluids that we need to drink each day varies from person to person.
The recommendation is to drink about 6 to 8 glasses of fluids a day to prevent dehydration. This is in addition to the fluid we get from food.
We need to drink more when the weather is hot or when we are active.

14. What is thirst?
The body’s first response when dehydration is detected is to signal the kidneys to conserve water.
The thirst response is initiated when 1-2% of body mass is lost due to dehydration so it is important to drink if we are thirsty.
The easiest way to spot that you might not be getting enough water is if your urine is a dark yellow colour during the day. If you are getting enough water your urine should be a pale straw colour. 
Headache and tiredness are also symptoms.

15. Which population groups may be at risk of dehydration?
Older adults may have a weaker sense of thirst. If necessary they should be helped and encouraged to drink regularly. 
Children need plenty of fluid and they should be encouraged to drink regularly, especially if they are very active. 
People who are very physically active should drink enough fluid to replace the water loss through sweating.

16. What happens if we drink too much water?
It can lead to ‘water intoxication’ with potentially life threatening hyponatraemia.
This is caused when the concentration of sodium in the blood gets too low.
Symptoms of hyponatremia include nausea, vomiting and headache.

17. Review of the learning objectives
To know the functions and sources of dietary fibre.
To understand the health benefits of dietary fibre.
To know the functions and sources of water.
To understand the principles of fluid balance.

18. Question
True or false?
All types of dietary fibre have the same functions.
True
False

19. False. Different types of dietary fibre have different functions in the body – some help prevent constipation, some help maintain normal blood cholesterol levels.
Next question

20. Question
On average, how much dietary fibre should adults eat each day?
10g/ day
14g/ day
18g/ day
30g/ day

21. Wrong answer.
Try again
Next question

22. Correct answer.
Next question

23. Question
True or false?
The easiest way to check for dehydration is by looking at urine colour.
True
False

24. True. If you are dehydrated, your urine is a dark yellow colour; if you are getting enough water your urine should be a pale straw colour. 
Next question

25. Question
What proportion of the body is water?
About one-third
About one-half
About two-thirds

26. Wrong answer.
Try again
Next question

27. Correct answer.
Next question

28. Question
Which of the following is/are symptom(s) of mild dehydration?
a) Headaches
b) Irritability
c) Thirst
d) Loss of concentration
e) All of the above a) b) c) d) e)

29. Wrong answer.
Try again
The end

30. Correct answer.
The end

31. Quiz- Kahoot
Open the link below on the main screen and get students to log onto kahoot.it on their tablets or smartphones.
They can then enter the code (that will come up on the main screen when you start the game) and their own nickname.
They can then play along with the quiz choosing the multiple choice answers that correspond with the questions on the main screen. There will then be a leaderboard of the scores after each question and at the end.

32. The information in this PowerPoint presentation has been taken from For more information on fibre, click here and for more information on water and fluid recommendations, click here.