National curriculum links
KS3, Sc4, Unit 7I - Energy resources.

Main learning objectives
Pupils learn:
that energy is measured in joules;
to use the joule and the calorie as units for communicating about energy;
about global disparity of access to food as an energy resource.

Food frenzy?

Comparing the consumption of food energy in Bangladesh, the UK and the USA

The amounts are shown in kilojoules and kilocalories.

The joule is the up-to-date scientific unit used for energy – a kilojoule is equal to one thousand (1,000) joules.

There is an older unit of energy, still used by a lot of people, called a calorie. These are often given as well as joules in the nutritional information on food packaging. A kilocalorie is equal to one thousand calories. To make it even more confusing, sometimes when people are referring to food, they write “Calorie” (with a capital “C”) to mean kilocalorie.