What is the difference between kcal and kJ?

The energy content of foods is given both in kcal and kJ. What is the difference between the units?

The internationally accepted standard unit for energy in the SI system is the joule (J).

Because many people still use calories, the food content of energy is given both in kilojoules (kJ) and as kilocalories (kcal) in the Food Composition table.

  • 1 kJ = 0,239 kcal
  • 1 kcal = 4,184 kJ