How many Kilojoules in a Calorie?

Kilojoules, Calories, KJ, Cal, Cals… What’s the story? It’s so confusing!

We’re not big on Calorie counting here at EFM, however having a basic understanding of how much energy is in the food we consume is important, especially when the energy content of food can be displayed in numerous ways.

Kilojoules vs Calories:

Both kilojoules and Calories provide a measurement of the energy in food, which is important to understand because and energy that is consumed and not used, is stored as fat in the body.

What is the conversion?

One Calorie (Cal) is equal to 4.186 kilojoules (kJ).

For example, if you have a food item that contains 418.6 Kilojoules, that is equivalent to 100 Calories.

Understanding Kilojoules in food

When we consume foods, we are typically taking in a quantity of fat, carbohydrate and protein. Each play an important role in helping the body to function properly, however each provide a different amount of energy, for example, the energy value per gram of various food components includes:

  • fat – 37 kJ (9 Cal) – not all fatty acids may provide the same amount of energy
  • alcohol – 29 kJ (7 Cal)
  • carbohydrates – 16 kJ (4 Cal) – not all carbohydrates may provide the same amount of energy
  • protein – 17 kJ (4 Cal)

Again, we do not advocate sticking to a calorie counting regime, however as you can see above, on a per gram basis, fat contains over twice the amount of energy that protein.

Nice to know!


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