Calories & Kilojoules – and how to convert them

Some food labels list details in kilojoules, others in Calories and some even both which can be quite confusing. However, Calories and Kilojoules are two ways to measure the same thing: Energy. The energy value of Food and the amount of energy that our bodies burn. Here is a quick guide to understanding the basics of calories and kilojoules.

calories-kilojoules Kilojoules 
A Kilojoule is a unit of energy which refers to the energy value of food, and the amount that we burn during activities.
Food energy is often measured in Kilojoules and Physical activities (energy burned) in Calories.
Kilojoules and Calories are very much the same as feet and meters, the are just two different measures of the same thing.

One Calorie has the same energy value as 4.184 Kilojoules (kJ)
So to convert kilojoules to Calories all you need to do is divide the kilojoules by 4.184 (or 4 to get a rough estimate).

“Calories” are written with the capital letter “C” and should not be confused with “calories” which is the small (gram) calories which is used to measure the amount of energy required to heat water.

There are 1000 small calories in 1 (large) Calorie: 1 Calorie = 1 kilocalorie = 1000 calories.

But just remember:

1 Calorie = 4.184 Kilojoules (kJ)
Divide the Kilojoule figure by 4.184 (or 4) to get the Calorie value.

Example: 2000 kilojoules = 2000/4.184 = 478 Calories.

Food energy
The different foods that we eat provide us with energy (kilojoules), and depending on the amount of fat, protein and carbohydrate the food contains will give us the energy figure.

Fats and alcohol are the most calorie dense foods/beverages, and should therefore only be consumed in moderation. However not all fats are broken down equally, and some fats such as Omega 3 from fish oils (polysaturated) may be more easily used up during exercise, than other types of fats.

Carbohydrates are broken down into sugars (glucose), and foods with a high GI (glycemic index) are metabolized faster. A limited amount of high GI foods (white bread, pasta dishes, soft drinks, chocolate bars etc) is preferred to avoid weight gain.

Everyone’s energy requirements differ depending on gender, age, genetics, metabolism and physical activity level. Men generally have greater energy requirements than women due to muscle tissue. The more muscles a person has, the speed at which he/she burns kilojoules will be higher. However there are some standard guidelines to follow regarding daily energy needs which is 2500 calories a day for men and 2000 calories a day for women (higher if pregnant).

Managing a healthy weight becomes a lot easier when we understand how to count calories & kilojoules. If we consume more energy than we burn, we put on weight, and if we burn more energy than we eat per day then we lose weight. It is as simple as that.

Reference: Better Health Channel

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Healthy living hub enthusiasts are passionate about well-being and healthy lifestyles, and we aim to help people return to their best by motivating and promoting simple changes in lifestyle and food habits. We encourage the mind body connection and believe in an all-round approach to health and personal well-being.
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