Chapter 1: Nutrients

• It's a macronutrient 

Amino acids (AAs)

• These are ‘building blocks’ that make up protein molecules
• There are at least 20 different amino acids.
• Ten AAs are essential for children
• Eight for adults
• High biological value (HBV) proteins contain all ten essential AAs
• Low biological value (LBV) proteins are missing one or more essential AAs
• Eating two or more LBV protein foods together you will get all the essential AAs
• This is called protein complementation, e.g. beans on toast, lentil soup and bread, rice and peas.

• Makes the body grow.
• Repairs the body when it is injured.
• Gives the body energy.

HBV protein foods

• Meat, poultry, fish, eggs, milk, cheese, yoghurt, soya beans, quinoa.

LBV protein foods

• Beans, peas, lentils
• Cereals (rice, wheat, oats, barley, rye, millet, sorghum)
• Cereal products (bread, pasta, etc.), nuts, seeds, gelatine.

Protein alternatives

• Made from soya e.g tofu, tempeh, textured vegetable protein
• Mycoprotein made from a high-protein fungus: e.g. Quorn.

• Children do not grow properly
• Hair loss occurs
• Skins and nails will be in poor condition
• Infections can easily develop
• Food is digested poorly

• Excess is stored as fat
• Weight gain and obesity
• Puts a strain on the liver and kidneys

• It's a macronutrient
• Fats are solid at room temperature
• Oils are liquid at room temperature
• Fat/oil molecules are called triglycerides
• They have the same structure and same energy value

Triglycerides: These are made of three fatty acids and one part glycerol

Monounsaturated fatty acid: Type of fatty acid found in solid fats and liquid oils

Saturated fatty acids: Found mainly in solid fats, e.g. butter, lard, suet, block vegetable fat, ghee, the fat in meat, palm oil, coconut and chocolate

Unsaturated fatty acids: Fatty acids found mainly in liquid plant oils e.g olive, rapeseed, sunflower and corn, oily fish, avocado pears, nuts, seeds and some vegetable fat spreads

• Gives energy which is stored in the body.
• Insulates the body from the cold.
• Protects bones and kidneys from physical damage.
• Provides vitamins A, D, E and K.

Visible fats and oils

• Fats/oils in a food that you can see e.g fat in meat, oil in tuna, butter, lard, suet, block vegetable fat, ghee, and plant oils, such as olive, palm and sunflower oil. 

Invisible fats and oils

• Fats/oils in a food that you cannot see e.g in cakes, pastries, potato crisps, biscuits, chocolate, nuts, fried foods, meat products, etc.

• Weight loss
• Feeling cold
• Bruising because of loss of protective fat layer
• Lack of vitamins A, D, E and K

• Excess is stored as fat
• Weight gain and obesity
• Organs such as the liver store fat in them which stops them working properly

• It's a macronutrient
• Made by plants during photosynthesis.

Sugars

Monosaccharides: glucose, fructose and galactose.

Disaccharides: sucrose, lactose and maltose.

Complex carbohydrates

Polysaccharides: starch, pectin, dextrin and dietary fibre (also called non-starch polysaccharide – NSP).

• Main source of energy.
• To get rid of waste products (dietary fibre).

Glucose:

• Ripe fruits and vegetables e.g. apples, onions, beetroot, parsnip, sweet potato
• Available in drinks, tablets and powder form

Fructose:

• Fruits, vegetables and honey
• High fructose corn syrup (HFCS) used as a sweetener in many processed foods and carbonated soft drinks

Galactose:

• Milk from mammals

Maltose:

• Barley
• A syrup (malt extract), added to breakfast cereals
• Biscuits, hot drink powders and confectionery

Sucrose: 

• ‘Sugar’ from sugar cane/sugar beet
• This is used in cooking/many processed foods
• Drinks and confectionery.

Lactose:

• Milk and milk products

Starch:

• Cereals e.g wheat, rice, oats, barley, maize
• Cereal products e.g breakfast cereals, pasta
• Starchy vegetables e.g potatoes, yams, sweet potatoes, parsnips, pumpkins, butternut squash

Pectin:

• Some fruits e.g oranges, lemons, limes, apples, apricots, plums, greengages
• Some root vegetables e.g carrots

Dextrin:

• Formed when starchy foods e.g bread, cakes, biscuits are baked or toasted

Dietary fibre/non-starch polysaccharide (NSP):

• Wholegrain cereals and cereal products e.g pasta, flour
• Fruits and vegetables, especially with skins left on e.g peas, beans, lentils

• Lack of energy/tiredness
• Weight loss
• Severe weakness
• Not enough fibre causes constipation

• Excess stored as fat
• Weight gain and obesity

• Micronutrients – needed in small amounts.
• Fat soluble – A, D, E and K.
• Water soluble – B group, C.

Vitamin A:

Animal foods (retinol): milk, cheese; butter; eggs, liver, kidney, oily fish; vegetable fat spreads (added by law).

Plant foods (beta carotene): dark green leaves of cabbage, spinach, kale, lettuce; orange/yellow/red vegetables and fruits e.g. carrots, apricots, mango, papaya, peppers, tomatoes

Vitamin D: Sunlight on skin, oily fish, meat, eggs, butter, vegetable fat spreads 

Vitamin E: Soya, corn oil, olive oil, nuts, seeds, whole wheat, vegetable fat spreads.

VitaminK: Green leafy vegetables, liver, cheese, green tea.

Vitamin B1: Meat, especially pork, milk, cheese, eggs, vegetables, fresh and dried fruit, wholemeal bread

Vitamin B2: Milk and milk products, eggs, fortified breakfast rice, mushrooms

Vitamin B3: Beef, pork, wheat flour, maize flour, eggs, milk

Vitamin B9: Green leafy vegetables, yeast extract e.g Marmite, peas, chickpeas, asparagus, whole grain rice, fruits

Vitamin B12: Liver, meat, fish, cheese, fortified breakfast cereals, yeast

Vitamin C: Fruits and vegetables, especially citrus fruits e.g oranges, lemons, limes and grapefruit, blackcurrants, kiwi fruit, cabbage, broccoli, new potatoes, milk and liver.

Vitamin A: Dry and infected skin, night-blindness leading to total blindness, poor growth.

Vitamin D: Bones weaken and bend (rickets in children/osteomalacia in adults)

Vitamin E: Deficiency is rare

Vitamin K: Rare but may happen in new-born babies

Vitamin B1: Beri-beri– affects nerves and muscles.

Vitamin B2: Rare – sore corners of mouth

Vitamin B3: Pellagra – diarrhoea, dementia, dermatitis.

Vitamin B9: Megaloblastic anaemia; possibly spina bifida in unborn babies.

Vitamin B12: Pernicious anaemia.

Vitamin C: Anaemia, bleeding under skin, loose teeth, wounds do not heal, scurvy

Vitamin A: Healthy skin, to see in dim light; growth of children, moist and healthy mucus membranes; antioxidant (helps prevent heart disease and cancers)

Vitamin D: Helps the body absorb calcium, helps calcium be laid down in bones and teeth for strength

Vitamin E: Antioxidant (helps prevent heart disease and cancers)

Vitamin K: Helps blood clot after injury

Vitamin B1: Enables energy to be released from carbohydrates

Vitamin B2: Enables energy to be released from carbohydrates, fats and proteins

Vitamin B3: Enables energy to be released from carbohydrates, fats and proteins

Vitamin B9: Makes healthy red blood cells; helps prevent spinal cord defects in unborn babies

Vitamin B12: Makes healthy red blood cells; healthy nerve cells

Vitamin C: Helps the body absorb iron, maintains connective tissue to bind body cells together, antioxidant (helps prevent heart disease and cancers).

• Micronutrients – needed in small amounts
• Calcium, iron, sodium, fluoride, iodine, phosphorus

Calcium: Strong bones and teeth; makes nerves and muscles work; helps blood clot after injury

Iron: Makes haemoglobin in red blood cells to carry oxygen to produce energy in body cells

Sodium: Controls water in body, nerves and muscles

Fluoride: Strengthens tooth enamel and bones

Iodine: Produces thyroxin in thyroid gland to control metabolic rate of body

Phosphorus: Strong bones and teeth; energy release; makes cell membranes, especially in the brain.

Calcium: Bones and teeth weaken; bones bend; nerves and muscles do not work properly; blood will not clot after injury 

Iron: Anaemia; tiredness, lack of energy, weakness, pale skin complexion, weak and spilt nails

Sodium: Muscle cramps

Fluoride: Weak enamel – more chance of tooth decay

Iodine: Swelling in neck (goitre)

Phosphorus: This is rare

Calcium: Milk, cheese, yoghurt; green leafy vegetables; canned fish; enriched soya drinks; flour.

Iron: Red meat, kidney, liver; wholemeal bread, added to wheat flour; green leafy vegetables e.g. watercress, spinach, cabbage; egg yolk; dried apricots; lentils; cocoa, plain chocolate; curry powder; 

Sodium: Salt; salted foods; cheese, yeast extract, stock cubes, gravies and seasonings, snack foods, canned fish, bacon, ham, dried fish, soy sauce, salted butter, fast foods 

Fluoride:Fish and seafood, tea, some water supplies

Iodine: Seafood, vegetable, dairy foods

Phosphorus: Wide range of foods

Sodium: Too much salt leads to high blood pressure and cardiovascular disease

Fluoride: May lead to discoloured teeth

Iron: Poisonous if too much taken e.g in supplements.

• Controls body temperature
• Needed for chemical reactions in body
• Removes waste products from body
• Keeps mucous membranes moist and healthy
• Keeps skin moist and healthy
• Needed for all body fluids
• Found in all body cells

• Drinking water (tap water).
• Naturally found in many foods e.g milk, milk products, fruit, vegetables, meat, fish, eggs
• Added to many foods e.g soup, sauces, pastries, boiled rice, pasta, beans, pulses etc.

• Thirst
• Headache
• Dehydration – urine becomes very dark
• Feeling weak and sick
• Body overheats
• Confusion
• Blood pressure and heart rate change

• Substances in the blood become over-diluted
• Vital organs in the body start to fail, e.g. heart, kidneys
• May cause death