NUTRITION

© PDST Home Economics

Why do you eat food?

• To give a feeling of fullness• The social aspect• To get goodness out of it• To prevent illnesses

What goodness do we get from food?

• Strong bones and teeth• Energy• Growth• Prevents constipation• General good health

Nutrients in foods do these and more jobs in the

body

PROTEIN

WATER

CARBOHYDRATE

FAT

MINERALS

VITAMINS

NUTRIENTS

Nutrients

Macro Nutrients• Our bodies need these

in large amounts• They are too big to be

absorbed by the body so they must be broken down

• Protein, fats and carbohydrates

Micro Nutrients• Our bodies need these

in small amounts• They are small enough

to be absorbed by the body once eaten

• Minerals and vitamins

QUESTION TIME

• Name the six nutrients• Do we need macro nutrients in small amounts or

large amounts?• Do we need micro nutrients in small amounts or

large amounts• Name the macro nutrients• Name the micro nutrients• Do macro / micronutrients need to be broken

down before the body can use them?

PROTEIN

SOURCES

CLASSIFY

FUNCTIONS

STRUCTURE

PROTEIN

PROTEIN STRUCTURE

• Proteins are made up of amino acids

• Amino acids are joined together with peptide links

CLASSIFICATION OF PROTEIN

HIGH BIOLOGICAL VALUE PROTEIN

• Contains all essential amino acids

• Essential amino acids are the amino acids the body needs but cannot make so must get them from food

• Normally come from animal foods

LOW BIOLOGICAL VALUE PROTEIN

• Do not contain all essential amino acids

• Normally come from vegetable foods

SOURCES OF PROTEIN

High biological value • Meat, Fish, Eggs

Cheese

Low biological value• Peas, Beans, Nuts,

Pasta

BIOLOGICAL FUNCTIONS OF PROTEIN

• Growth

• Repair of worn out or damaged cells

• Production of hormones, enzymes and antibodies.• Gives us energy and heats our body

QUESTION TIME

• What are protein chains made up from?• Classify protein into its two groups• Name three animal protein foods• Name three vegetable protein foods• Name three biological functions of protein• What link joins the amino acids together along

the protein chain• What are essential amino acids

LIPIDS / FATS

SOURCES

CLASSIFY

FUNCTIONS

STRUCTURE

LIPIDS

STRUCTURE OF FATS

• Lipids / Fats are made up of 1 glycerol unit joined to 3 fatty acid units

CLASSIFICATION & SOURCES OF FATS

SATURATED FATS• Milk, Cheese, Meat,

Butter

UNSATURATED FATS• Oil, Oily Fish, Nuts,

Seeds

BIOLOGICAL FUNCTIONS OF FATS

• Gives our bodies heat and energy• A layer of fat in the skin insulates our body

keeping us warm

• Delicate organs in the body like the heart and kidneys are protected by a layer of fat

around them• We get fat soluble vitamins

A,D,E,K from fats

HOW TO REDUCE FAT INTAKE

• Grill, bake, boil or microwave instead of frying• Cut visible fats of meat• Use low fat foods• Cut down on fatty foods like chocolate, crisps,

chips etc..

QUESTION TIME

• Describe the structure of fats• Classify fats into two groups• Name three sources of fats under each

classification• List 5 biological functions of fats• Suggest 4 ways to reduce dietary intake of fats

CARBOHYDRATE

SOURCES

CLASSIFY

FUNCTIONS

STRUCTURE

CARBOHYDRATE

CARBOHYDRATES

• Carbohydrates are made up of two or more simple sugars joined together. Glucose is a simple sugar unit

CLASSIFICATION & SOURCES OF CARBOHYDRATES

SUGAR

Honey, Fruit, Ice cream

FIBRE

Brown Bread, Whole meal pasta / rice, nuts seeds, fruit and vegetable skins

Potatoes, Pasta, Rice, bread

STARCH

BIOLOGICAL FUNCTIONS OF CARBOHYDRATES

• Provides heat and energy• Fibre rich foods fill you up

• Fibre helps prevent constipation and other bowel problems

HOW TO INCREASE FIBRE INTAKE

• Eat more whole meal cereals like brown bread, brown pasta, brown rice instead of white

• Eat high fibre breakfast cereals • Eat more fruit and vegetables• Eat more nuts and seeds

HOW TO REDUCE SUGAR INTAKE

• Eat non-sugary breakfast cereals• Choose reduced sugar jams and jellies• Use sweeteners in tea / coffee instead of sugar• If eating canned fruit make sure it’s in its own

juice not in syrup

QUESTION TIME

• Carbohydrates are made up of simple sugar units called ________?

• Classify carbohydrates into three groups• Give two sources of each type of CHO.• List 3 functions of carbohydrates• Suggest some ways to increase intake of dietary

fibre• Suggest ways to reduce sugar intake

VITAMINS

CLASSIFICATION OF VITAMINS

WATER SOLUBLE FAT SOLUBLE

VITAMIN

• FUNCTIONS: Needed for healthy nervous system, growth and it is needed to release energy from food.

• SOURCES: Meat, Fish, Cheese, Eggs

• DEFICIENCY DISEASE:• Beri-beri & pellagra

Beri-beri & pellagra

VITAMIN

• FUNCTIONS: • Needed for good general health, for healthy skin

and gums.

• Needed to help absorb iron• It helps make connective tissue, which can help

the healing of wounds.

VITAMIN

• SOURCES:• Fresh fruit and vegetables

• DEFICIENCY DISEASE: Scurvy, Anaemia, delayed healing of wounds

SCURVY

• Scurvy was a disease commonly found among sailors who ate mainly meat and crackers, the sailors rarely had fresh fruit and vegetables

PREVENTING LOSS OF VITAMIN • Vitamin C is destroyed very easily, to keep as

much vitamin C in food as possible, do the following:

• Buy fresh fruit and vegetables not wilted• Use / cook fruit and vegetables when fresh don’t

buy them a week before use• Eat vegetables soon after they are cooked they

loose vitamin C if they are kept warm for a long time

• Don’t use bread soda to brighten the colour of the vegetable as it destroys vitamin c.

VITAMIN

FUNCTIONS: Works with calcium to make strong bones and teeth

SOURCES: Sunshine, oily fish, eggs, cheese, cod liver oil

DEFICIENCY DISEASE:Rickets, Osteoporosis, tooth decay

RICKETS

• Vitamin D works with calcium to make strong bones and teeth. Child with rickets will have soft, badly formed bones and teeth that are prone to tooth decay

OSTEOPOROSIS

• Commonly known as “brittle bone disease” bones are fragile and break easily

VITAMIN

• FUNCTIONS: Growth, Healthy Eyes, Healthy Skin, Healthy lining tissue in the nose and throat etc..

VITAMIN

• SOURCES: Fish liver oil, oily fish, Eggs, Milk, Carrots

• DEFICIENCY DISEASESSlowed growth. Lining of nose and throat become dry and irritated.Night Blindness.

VITAMIN

• FUNCTIONS: Helps the blood to clot • Sources: Cod liver oil, cabbage, spinach,

cauliflower

• Deficiency Disease: Blood clots slowly or in severe deficiencies not at

all

VITAMIN

• Functions: Acts as an antioxidant which are thought to reduce to appearance of aging and the incidence of cancer and coronary heart disease

• Sources: Eggs, Nuts, Cereals, Sunflower seeds• Deficiency Disease: Rare

QUESTION TIME• Classify vitamins into two groups• List two functions of Vitamin B• List two sources of Vitamin B• List two deficiencies caused by lack of Vitamin B• List two functions of vitamin C• List two sources of vitamin C• List two deficiencies caused by a diet lacking in

vitamin C• Name three ways to reduce the loss of Vitamin C in

food

QUESTION TIME• Name one function of each of the following

vitamins A, D, E, K• Name two sources of vitamins A,D, E , K• From which of the following nutrients is it rare to

get a deficiency disease from A, D, E or K• Name two deficiencies of a diet lacking in vitamin

D• Name two deficiencies of a diet lacking in Vitamin

A• Name one deficiency disease for vitamin K

MINERALS

MINERALS

CALCIUM

IRON

IODINE

FLOURINE

SODIUM

PHOSPHOROUS

IRON

• FUNCTION: Needed to make haemoglobin. Haemoglobin is found in red blood cells and is needed to bring oxygen around the body to give us energy.

• When the body does not get enough iron it gets tired weak and run down this eventually leads to a

• DEFICIENCY DISEASE: called anaemia

SOURCES OF IRON

Good sources• Red Meat and

offal

Sources that need Vitamin C

• Whole meal Bread, green vegetables, cereals, eggs, oily fish

IRON DEFICIENCY

• DEFICIENCY DISEASE: Iron deficiency anaemia: A substance called haemoglobin is found in our red blood cells, this substance is needed to carry oxygen to all the cells in the body to give us energy. Iron is needed to make haemoglobin. If you do not eat enough iron you eventually get anaemia this results in the sufferer becoming pale, tired, weak and dizzy.

CALCIUM

FUNCTION: To build strong bones and teeth

Sources: Milk, Cheese, yoghurt, tinned fish

Deficiency Disease: Rickets, Osteoporosis, Tooth decay

FLOURINE

• FUNCTION: Healthy Teeth

• Sources: Drinking Water, Toothpaste and Fish

• Deficiency: Tooth Decay

IODINE

• FUNCTION : Needed for healthy thyroid gland

• Sources: Seaweed, Cereals, Milk, Sea fish

• Deficiency: Goitre

PHOSPHORUS

• FUNCTION: Works with calcium for strong bones and teeth

• SOURCES: Milk, fish, cheese, eggs

• DEFICIENCY: Rare

SODIUM

• FUNCTION: Controls water balance in the body

• SOURCES: Table salt, bacon, cheese, crisps, tuc biscuits

• DEFICIENCY: • Muscular cramps