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Nutrients
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
Nutrients
• Nutrients perform different functions in the
body.
• The body needs different amounts of each
nutrient. Specific figures (Dietary Reference
Values) are published by the government.
• Healthy eating means selecting foods that will
provide the nutrients you need.
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
Energy
• Measured in kilocalories (kcal) or kilojoules
(kj).
• Provided by carbohydrates, fat, protein and
alcohol.
• Balance the energy input from food with the
energy output through activity – this helps to
control body weight.
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
Fat
• A very concentrated source of energy – fat
contains more than twice as much energy as
sugar or starch.
• Should provide 30 – 35% of energy.
• Two types: saturated and unsaturated.
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
Unsaturated fat
• Unsaturated fat is present in oily fish and
foods from plants (oils, nuts and seeds).
• Unsaturated fat reduces the cholesterol
level in the body.
• Two types: monounsaturated and
polyunsaturated.
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
Saturated fat
• Present in foods from animal sources (meat,
milk, butter and cheese).
• Unhealthy as it pushes up blood cholesterol.
• Switch to foods containing unsaturated fat –
use oil instead of butter, eat oily fish and white
meat.
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
Percentage of fat in some foods
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
Types of fats
Mostly saturated
Butter
Lard, suet, dripping
Hard margarines
Ghee
Creamed coconut and
coconut oil
Palm oil and palm
kernel oil
Full-fat milk and diary
fat
Some meat fat
Mostly
monounsaturated
Olive oil
Rapeseed oil (canola)
Peanut oil
Some spreads
Some meat fat
Almond oil
Hazelnut oil
Mostly
polyunsaturated
Sunflower oil and
spread
Corn oil
Safflower oil
Walnut oil
Linseed oil
Soya oil/spread
Sesame oil
Oily fish
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
Main sources of fat in the diet
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
Carbohydrates
• Two types: starches and sugars.
• Starches occur in bread, cereal, rice, pasta
and potatoes.
• Starches should provide about 50% of energy.
• Starchy foods also contain some protein,
vitamins, minerals and fibre.
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
How much carbohydrate?
A diet high in carbohydrates (especially
unrefined) is recommended.
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
Sugars
• Sugars occur naturally in fruit and honey.
They are added to many manufactured foods.
• Tooth plaque contains bacteria which use
sugar to create acid, causing tooth decay
(more than half of UK teenagers suffer).
• Need to cut down on sugars.
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
Fibre
• The roughage in plant foods – wholegrain
cereals, pulses, fruit, vegetables and nuts.
• Good for the digestive system.
• Aim to eat about 30g per day.
• Most people only eat about 20g per day.
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
Main sources of carbohydrate
in the diet
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
Protein
• The ‘body-building’ nutrient found in animal
and vegetable foods, such as meat, fish,
cheese, eggs, cereals, pulses and nuts.
• Adults need 35 – 50g per day. That could be
provided by 100g of chicken or 200g of
baked beans and a yoghurt.
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
Main sources of protein in the diet
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
Vitamins and minerals
• Needed in minute amounts for many bodily
processes.
• Obtained from food.
• The government’s Dietary Reference Values
include amounts for nine vitamins and eleven
minerals.
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
Vitamin A
• Found in foods of animal origin.
• The body can make vitamin A from carotene,
which is found in orange juice and some fruit
and vegetables, such as carrots, sweet
potatoes and apricots.
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
B vitamins
• Several important functions in the body.
• Help release energy from food.
• Found in dairy products (especially vitamin
B2, riboflavin) and protein-rich foods.
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
Calcium
• Found in milk and dairy products.
• Needed for healthy bones and teeth.
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
Main sources of calcium
and iron in the diet
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
Some other minerals
• Iron: Needed for healthy blood; prevents
anaemia.
• Zinc: Needed for wound healing.
• Magnesium: Helps the body use energy from
food.
• All found in protein-rich foods.
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins
Salt (sodium chloride)
• Sodium is used to maintain the water balance
in the body. High intakes can raise blood
pressure, increasing the risk of stroke and
heart disease.
• Salt is added to many manufactured foods,
especially snacks.
• Aim for about 4g of salt per day. (The UK
average is estimated at 8g!)
Published by Hodder Education © 2010 D Foskett, J Campbell and P Paskins