This document discusses the functions of different nutrients found in food and their importance for maintaining good health. It explains that a balanced diet provides energy, allows growth and repair of tissues, and supports immune function. The main nutrients discussed are carbohydrates, proteins, fats, vitamins, minerals, and fluid. Carbohydrates provide energy and are found in sugars, starches, and fiber. Proteins aid growth and maintenance of tissues. Fats also provide energy and some vitamins. Vitamins and minerals perform essential roles but must be obtained through diet. A balanced intake of nutrients from a variety of foods is necessary for health.

1. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
REHIS FOOD & HEALTH
L2
The Function of Food

2. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Why do we need a healthy diet?
• To give us enough energy and nutrients to keep our bodies
working
• To allow growth and repair of our body tissue
• To give us the best protection against the risk of disease by
keeping our immune systems working.

3. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Nutritional Requirements for Health
• Fluid
• Energy from foods (measured in kcals)
• Nutrients
• Macronutrients (provide energy)
• Carbohydrates
• Protein (secondary source of energy)
• Fat
• Macronutrients (do not provide energy)
• Vitamins
• Minerals
No single food contains all nutrients therefore a balance/variety must be eaten. A balanced diet (for
example in the Eatwell guide) provides us with all the vitamins and minerals required.

4. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
What is needed for life?
Fluid
Vital as our bodies are made up of 70% fluid
Can only live approx. 3 days without fluid.
Energy from food (measured in Kilocalories of Kilojoules)
Macronutrients provides energy
Carbohydrates = 3.75kcal per gram
Protein = 4 kcal per gram
Fat = 9 kcal per gram
Alcohol = 7 kcal per gram
Micronutrients such as vitamins and minerals are essential
Micronutrients don’t provide energy.

5. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Carbohydrates: For energy
Consist of:
• Sugars
• Sugars added to food -chocolate, cakes, biscuits, sugary drinks,
honey, syrups and unsweetened fruit juice (free sugars)
• Milk and fruit (occur naturally in foods)
• Starches (bread, potatoes, rice, pasta)
• Dietary fibre
EAT LESS SUGARS – EAT MORE STARCHES
(preferably wholegrain)

6. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Carbohydrates: Sugars
Glucose, fructose (simple sugars) and sucrose (sugar), maltose
(in starch) and lactose (in milk) are all sugar.
• Sugars do not contain any extra nutrients such as vitamins or
minerals (empty calories)
• The frequent consumption of sugar is associated with dental
decay
• A high sugar intake can lead to
excessive amounts of calories

7. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Sugars
How much sugar is in our food?
12 teaspoons
10 tsp
Snickers 1 serving (1/3 King Size bar/35g)
Regular Size(59g) = 7¾ tsp
King Size (105g) = 13½ tsp

8. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.

9. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Free Sugars
Free Sugars are any sugars added to food or drink,
including those found naturally in foods (e.g. honey, syrup and
unsweetened fruit juices)
Sugars are naturally present in food, this includes milk sugars
(lactose) and those contained within the plant cells e.g. fruits,
Vegetables.
It is the free sugars (added sugars) that are damaging to health.
It is currently recommended that the average intake
of free sugars should be no more than 5% of total dietary energy.
This equates to no more than 30g per day for adults
and children less depending on their age.

10. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Carbohydrates: Starches
Most of the carbohydrate containing foods we consume (50% of
total energy) should be starchy, as they will provide us with a
slow, steady supply of energy as well as providing some vitamins,
minerals and fibre.
Examples of starchy food:
• bread, chapatis, potatoes, rice,
some fruit and vegetables,
pasta, breakfast cereals (watch
free sugars)

11. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Dietary fibre
Dietary fibre is a form of carbohydrate which the body cannot use for
energy. It passes through the digestive tract and keeps the bowels
functioning correctly.
30g of dietary fibre is required a day.
Most of us need to eat more.
A diet high in fibre can lower the risk of heart disease, stroke, diabetes
and bowel cancer.

12. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Carbohydrates: For Fibre
Soluble fibre
Slows digestion
e.g. constipation
Insoluble fibre
Speeds things up

13. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Dietary fibre - 2 Types (soluble and insoluble fibre)
Reduces blood cholesterol level -
moderates glucose levels in blood
Beneficial to those with diabetes
and raised cholesterol levels
Soluble fibre
• Oats
• Lentils
• Peas
• Dried beans
• Fruit and
vegetables.

14. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Dietary fibre - 2 Types (soluble and insoluble fibre)
• Bulks faeces - enhances passage of
waste products
• Insoluble fibre needs to hold fluid
as it swells in the bowel. Therefore
adequate fibre is important.
Lack of fibre associated with:
• constipation
• diverticular disease
• bowel cancer
• haemorrhoids (piles)
Insoluble fibre
• Wholemeal bread
• Wholemeal flour
• Brown pasta
• Bran-based cereals
e.g. bran flakes.
Unprocessed wheat bran no longer
recommended as can bind with
minerals.

15. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
What does
30g of fibre
look like?

16. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Dietary Fibre
Good gut bacteria thrive on fibre.
Having a healthy gut ensures that
maximum nutrient absorption can
take place.
Boost your gut health by
increasing the number and variety
of plant foods in your diet.

17. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.

18. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.

19. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Proteins: For growth, repair and maintenance of body tissues
and the production of hormones and enzymes
• The main sources of proteins are:
• Meats
• Offal
• Poultry
• Fish
• Eggs
• Cheese
• Milk
• Yoghurt
Vegetable sources include
nuts and pulses such as:
• Peas
• Beans
• Lentils
• Nuts
• TVP (soya)
• Myco proteins e.g.quorn
(From a Fungus – some quorn
contains egg white)

20. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Proteins: The main sources are from animal
Meat, Fish, Eggs, Dairy
• Proteins found in human body muscle, enzymes, hormones,
vital organs, e.g. lungs, intestinal walls, hair, skin, nails etc.
• Amino acids are the simple units which make up proteins. The
way the different amino acids are linked gives a protein tissue
its characteristics.
• Meat, eggs and milk all contain the 9 essential amino acids.
• Cereals, pulses and other vegetable sources of protein do not contain all of the essential
amino acids, therefore mixtures of these foods need to be eaten.
• Amino acids are needed for growth and repair of body tissues. These proteins are needed for
growth and repair.
• All of the essential amino acids should be present so that growth and repair can occur.

21. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Vegetarians
For vegetarians and vegans, nuts, pulses such as peas, beans and
lentils all provide protein.
• Vegetarians take milk, cheese, yoghurt and eggs. They may take
fish.
• Vegans take no products of animal origin.
• Lacto-ovo vegetarians take milk, cheese, yoghurt and eggs.
• Lacto vegetarians take milk, cheese and yoghurt.
• Demi-vegetarians take milk, cheese, yoghurt, eggs, fish and
chicken.
Those who eat meat, poultry and fish are called omnivores. They
make up the majority of the population.

22. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
What is fat?
Provides energy, some vitamins and essential fatty acids
• It is a very rich source of energy (high in calories)
• It gives us twice as much energy per gram, as carbohydrate
or protein foods
Types of fat
• Saturated fats
• Unsaturated fats
• Monounsaturated
• Polyunsaturated
• Essential fatty acids.

23. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Saturated fats
Foods high in saturated fat:
• Meat pies, sausages
• Butter and lard
• Hard cheese
• Cream
• Cake and biscuits
• Pastry
• Meat
• Coconut oil, palm oil
We should eat less of all types of fat, particularly saturated fat

24. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.

25. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Hydrogenated Fats or Trans fats
• When heated repeatedly at high temperatures unsaturated fats, e.g.
oils, harden and become saturated. This process is called
hydrogenation. Hydrogenated or Trans fats are typically found in
processed foods such as cakes and biscuits, as well as foods such as
chips and other deep-fried food.
• Trans fats are thought to have a similar effect to saturated fats in the
body (i.e. raising LDL cholesterol), therefore intake of trans fat should
be limited.
• To reduce consumption of food high in trans fats, you should avoid
products that list partially hydrogenated fat or oil, limit consumption
of processed (biscuits, cakes, pastries) and fried foods (especially from
restaurants and takeaways).

26. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Monounsaturated fats
Sources of monounsaturated fats are:
• Olive oil
• Rapeseed oil
• Nuts and seeds
• Walnut oil
• Avocado
• Some margarines and spreads are made from olive oil
EAT INSTEAD OF SATURATED FATS BUT NOT TOO MUCH.

27. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Polyunsaturated fats
Sources of polyunsaturated fats are:
• Corn oil
• Sunflower oil
• Vegetable oil
• Soya oil
• Fish oil
• Some margarines and spreads are made from polyunsaturated
fats (e.g. Sunflower).
Two polyunsaturated fats, Linoleic and Linolenic, are essential for health.
Cannot be made in body - essential fatty acids. (EFAs) .– we must eat these in our food
EAT INSTEAD OF SATURATED FATS BUT NOT TOO MUCH.

28. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Unsaturated fats (Omega-3 fatty acids)
Omega-3 fatty acids are found in:
• Fish oil
• Oily fish are the richest source and in a form that is easier
for our bodies to absorb than plant sources. (e.g. salmon,
mackerel anchovies, sardines, herring, trout and fresh tuna)
EAT MORE FISH – INCLUDING A PORTION OF OILY FISH EACH WEEK.
• Cannot be made by the body
• May help reduce the risk of heart disease

29. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.

30. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Omega-3 fatty acids
Omega-3 fatty acids are a particular type of polyunsaturated fat.
They can help prevent blood clotting.
Linoleic is an Omega-3 fatty acid (EFA)
Vegetarians - our bodies can also make Omega-3 fats from
rapeseed oil and from the oil in walnuts and soya.
Omega-3-fortified products contain relatively small amounts.
Omega-6 fatty acids are another group of fatty acids and can
reduce cholesterol levels - sources are wholegrain cereals, soya,
corn and sesame.

31. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Fluid
• 6 - 8 glasses/1.5 - 2 litres (approx.) of water
or other fluids
• Most foods contain water especially fruit and vegetables
DRINK PLENTY OF FLUID.

32. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Other fluids
• Fruit juice, smoothies, milk, tea,
coffee, sugar-free drinks
BUT
• Tea, coffee and cola contain
caffeine
• Fruit juice*, smoothies*, some
squashes and fizzy drinks contain
acids and/or free sugars
* Limit fruit juice and/or smoothies
to a total of 150ml a day.

33. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Alcohol: Not essential for body to function
The energy provided by alcohol
1g alcohol provides 7 kcal (29 kJ)
• A maximum of 14 units per week (men & women)
• Several alcohol-free days per week recommended
AVOID BINGE DRINKING
AVOID DRINKING IF PREGNANT.

34. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Calories in alcohol
• 1 pint of cider (2.6 units) = 1 doughnut (210 kcals)
• 1 pint of beer (2.3 units) = a large slice of pizza (197 kcals)
• 1 large glass of wine (3.3 units) = a slice of sponge cake (195 kcals)
• 1 bottle of alcopop (1.1 unit) = 1 onion ring (143 kcals)
• 2 bottles of beer (3.4 units) = a sirloin steak (275 kcals)
Source: www.drinkaware.co.uk

35. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Vitamins and minerals
• Required in small amounts
• Essential for our bodies to work properly, to help turn the food
we eat into energy and building strong bones and teeth. Vitamins
do not provide energy & cannot be made by the body.
Vitamins Minerals
• Fat soluble vitamins
• A, D, E, K
• Water soluble vitamins
• C, B
• Minerals
(e.g. calcium, iron)

36. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Fat soluble vitamins: Can be stored by the body
Vitamin A
•Liver
•Oily fish (e.g. herring)
and cod liver oil
•Dairy produce
•Carrots and green
leafy vegetables
•Peaches, nectarines
and dried apricots
Vitamin E
•Vegetable oils
•Nuts and seeds
•Eggs
•Wholegrain cereals
•Avocados and leafy
green vegetables
Vitamin D
• Sunlight
• Oily fish and
cod liver oil
• Eggs
• Margarine
• Meat
• Fortified
breakfast
cereals
Vitamin K
•Dark green leafy
vegetables
Some people may need
a Vitamin D supplement.

37. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Water soluble vitamins: Cannot be stored by the body
Vitamin C
•Citrus and soft fruits
•Fruit juices
•Potatoes, green and
salad vegetables
B Vitamins
•Meat
•Wholegrain breakfast cereals
•Bread
•Rice
Folate/folic acid
•Leafy green vegetables
•Wholegrains
•Nuts and pulses
•Fortified breakfast cereals. Folate/folic acid
B Vitamins
Vitamin C

38. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Minerals
Minerals - needed in small amounts
• Calcium
• Phosphorus
• Magnesium
• Sodium
• Potassium
• Chloride
• Sulphur
Still essential but needed in much
smaller amounts (often called trace
elements or minerals)
• Iron
• Copper
• Selenium
• Iodine
• Molybdenum
Minerals do not provide energy but are essential as part of a healthy diet, as they
are involved in the body’s chemical reactions, its structure and function. They also
have a role in protecting us from infections and boosting our immune systems.
• Cobalt
• Manganese
• Fluoride
• Zinc
Fluoride is considered as semi-essential as no requirement has been shown but it has beneficial effects on
dental health.

39. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Minerals
Calcium
• Cheese, yoghurt and milk
• Dark green leafy vegetables
• White bread and
fortified flour
• Canned fish
(if bones are eaten)
Phosphorus
•Milk, cheese
•Meat, fish and egg
Iron
•Offal and red meats
•Dark green vegetables
•Pulses and wholegrain cereals
•Eggs
•Nuts and seeds
•Dried fruit
•Fortified breakfast cereals
•Chocolate (dark).

40. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Minerals
Potassium
• Bananas
• All other fruit and vegetables
Sodium
• Salt
• Prawns
• Baked beans in tomato sauce
• Hard cheese
EAT LESS SODIUM/SALT

41. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
Selenium
• Red meat
• Fish
• Cereals
• Brazil nuts
Other minerals (trace elements)
Zinc
• Meat and meat products
• Milk and dairy produce
• Bread and other cereal products
• Eggs
• Beans, pulses and nuts
Fluoride
• Tea
• Seawater fish
• Water
Iodine
• Seafood
• Milk and diary
products
• Green vegetables.

42. tein, fat and fibre LEARNING INTENTIONS Students will have an understanding of the function of food and maintaining good health.
SUMMARY
• Carbohydrate – energy
• Protein – growth and repair
• Fat – energy
• No single food contains all nutrients so a variety must be eaten
• We need a balanced varied diet for energy, growth and repair
and protection against the risk of disease
• Healthy eating is:
• Eating a balanced diet
• Eating the right amount of food for how active you are.