Calories

Synonyms in the broadest sense

Kilokalorie (kcal), Kalorie (cal), Joule (J), Kilojoule (KJ)The name calories is derived from the Latin name calor and means heat. Calories are a unit of measurement for the energy contained in food, which is supplied to the human body through nutrition. The actual unit is given in joules or kilojoules, but it has not been able to prevail over calories in linguistic usage.

The EU directive stipulates that both kilocalories and kilojoules must be indicated on nutritional labelling. From January 01, 2010, the indication of the kilocalories will no longer be permitted. In linguistic usage, there are often difficulties with the term calorie-gram calorie or kilocalorie.

One kilo calorie (kcal) corresponds to 1000 calories (cal). The values indicated on the food always refer to kilocalories (kcal). The amount of (kilo)calories ingested through the food does not say anything about its value, only about the energy contained in it:

  • Greases
  • Carbohydrates
  • Protein

One calorie is the amount of thermal energy required to heat one gram of water by 1 Kelvin.

However, this value is temperature dependent, depending on the water composition and the ambient pressure. Water has a specific heat capacity of approx. 4.18 kJ/(kg-K) at 30- 50° C. The amount needed to heat 1 gram of air-free water from 14.5°C to 15.5°C is about 1 cal and corresponds to about 4.18 joules (J).

One kilocalorie hour (kcal/h) corresponds to 0, 00158PS. Conversely, one PS corresponds to 632, 415 kcal/h. 1 kg pure body fat contains an energy value of 7000 kcal.

In order to burn one kilo of body fat (see fat burning), one would have to burn 7000 kcal more than is taken in with food. However, the fact that the body prefers to burn carbohydrates rather than fats is problematic. The basal metabolic rate of a man varies depending on his height, body weight, body fat percentage, occupational activity, sporting activity, external conditions, etc.

Therefore, it is not possible to make any significant interpersonal general statements regarding the basal metabolic rate. However, due to the increased muscle mass, men burn more calories per day than women. Fats are more energy-rich than proteins, so one gram of fat contains 9 kilocalories, while carbohydrates and protein contain only 4 kilocalories. Fats are therefore more energy-rich than carbohydrates, but are more difficult to convert into energy and are therefore only burned during moderate physical activity.