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 FAT WATER NUTRIENTS MINERALS CARBOHYDRATE VITAMINS

Nutrients Macro Nutrients Micro 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 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

CLASSIFY FUNCTIONS SOURCES PROTEIN STRUCTURE

PROTEIN STRUCTURE Proteins are made up of amino acids Amino acids are joined together with peptide links

CLASSIFICATION OF PROTEIN HIGH BIOLOGICAL VALUE PROTEIN LOW 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 Do not contain all essential amino acids Normally come from vegetable foods

SOURCES OF PROTEIN High biological value Low biological value Meat, Fish, Eggs Cheese 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

CLASSIFY FUNCTIONS SOURCES LIPIDS STRUCTURE

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

CLASSIFICATION & SOURCES OF FATS SATURATED FATS UNSATURATED FATS Milk, Cheese, Meat, Butter 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

CLASSIFY FUNCTIONS SOURCES CARBOHYDRATE STRUCTURE

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

CLASSIFICATION & SOURCES OF CARBOHYDRATES SUGAR STARCH FIBRE Honey, Fruit, Ice cream Potatoes, Pasta, Rice, bread Brown Bread, Whole meal pasta / rice, nuts seeds, fruit and vegetable skins

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 Symptoms of dry beriberi include: Difficulty walking Loss of feeling (sensation) in hands and feet Loss of muscle function or paralysis of the lower legs Mental confusion/speech difficulties Pain Strange eye movements (nystagmus) Tingling Vomiting Symptoms of wet beriberi include: Awakening at night short of breath Increased heart rate Shortness of breath with activity Swelling of the lower legs Pellagra: tongue and skin become sore, as the condition progresses the symptoms get worse, diarrhea, dermatitis, depression, dementia and death.

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. As the name implies, connective tissue serves a "connecting" function. It supports and binds other tissues loose connective tissue. It holds organs in place Specialized Connective Tissues Adipose Adipose tissue is a form of loose connective tissue that stores fat. Cartilage Cartilage is a form of fibrous connective tissue that is composed of closely packed collagenous fibers in a rubbery gelatinous substance called chondrin. The skeletons of sharks and human embryos are composed of cartilage. Cartilage also provides flexible support for certain structures in adult humans including the nose, trachea and ears. Bone Bone is a type of mineralized connective tissue that contains collagen and calcium phosphate, a mineral crystal. Calcium phosphate gives bone its firmness.

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 DISEASES Slowed 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

PHOSPHOROUS SODIUM CALCIUM MINERALS FLOURINE IRON IODINE

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 Sources that need Vitamin C Red Meat and offal 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 A goitre or goiter (Latin gutteria, struma), also called a bronchocele, is a swelling in the thyroid gland,[1] which can lead to a swelling of the neck or larynx (voice box). Goitre usually occurs when the thyroid gland is not functioning properly

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