Page 128 - York Global Science 6 - Physical Science
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Gender Age Activity level
Males need more energy than Younger people need more Active people need more
females. energy than older people. energy than sedentary people.
Energy is measured in joules (J) or kilojoules (kJ).
1 kilojoule = 1000 joules
Most 10-year-old girls need about 8100 kJ per day and most 10-year-old boys
need about 8500 kJ.
• If you do not take in enough energy from food, you will lose weight (get
thinner) and your body may not work as well.
• If you take in more energy than you need, your body uses this energy to
make fat. This can make you put on weight (get fatter), which may cause
bad health problems.
To check that you are taking in the right amount of energy, you can look at the
labels on food packaging.
Food labels give you lots of information about what is in the food. They also
tell you how much energy the food has. This helps you to choose what to eat
in the best way.
The chemical energy in food is often shown per 100 g or per 100 ml. You must
check the size of the packet if you want to know the total amount of energy
there is in it.
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