What is Calorie?

Calorie is the unit of energy. The word comes from Latin calor, meaning ‘heat’. It is defined as the quantity of heat, needed to raise 1 gm of water at sea-level pressure from 14.5°C to 15.5°C (technically known as the 15°C Calorie or gram calorie).

Another type of Calorie exists which is known as food calorie or kilogram calorie or large calorie which is defined in terms of the kilogram rather than the gram. It is equal to 1000 small calories or 1 kilocalorie.