Are calories just calories?

27. 1. 2019

Are calories really just a calories, are all calories the same?

At the beginning we are going to define what calories are. Calorie (cal) is physical unit for energy determined as source of heat which is necessary for heating one gram of water at 1°C at a pressure of 1°C. Since the specific heat of the water depends on the temperature it does not care if the temperature is heated by one degree of water. In practice five different definitions have been introduced but they all use the term "calories":

  • calories define at 15 °C,
  • calories define at 4 °C,
  • average calories in the range 1 °C – 100 °C,
  • international calories determined by the International Steam Table
  • thermochemical calories

The calories determined at 15°C are determined as the heat needed to heat one gram of water at atmospheric pressure from a temperature of 14.5°C to 15.5°C and is approximately equal to 4.1855 J. International calorie is approximately equivalent to 4.1868 J, and thermochemical calorie to 4.184 J.

But now let's focus on whether all calories are equivalent. Before I even begin to explain my answer is NO! Let's see why:

The problem occurs primarily with some bodybuilders and people who want to lose some fat mass (by rapid procedure) but they don't have enough knowledge or "don't want to" be aware of what research suggests. In particular it is a popular excuse "calories out - calories in." By this I think you are eating a little less calories than your daily consumption and finally losing weight (or vice versa for bodybuilders who are trying to gain weight). By doing so, they think they can eat anything to satisfy the goal they have set (because you can lose weight if you are on fast food, just that there is no excess of calories or vice versa).


Wild Norwegian salmon (200 g) baked on coconut oil oven, ordinary homemade white potato baked on  coconut oil in the oven (300 g), 100 g of bio Greek yogurt and spices (chilli, curcuma, pepper). Preparation and baking takes about 60 minutes.

  • Calories: 896.9
  • Protein: 50
  • Carbohydrates 66.9
  • Fats: 44.7



Chicken (200 g) from the supermarket, baked on high-temperature sunflower oil, quick-frozen French fries (200 g), baked on sunflower oil at high temperature and ice tea (2 dl).

  • Calories: 1124
  • Proteins: 57
  • Carbohydrates 107
  • Fats: 52


As we can see in macronutrients meals are not that different. What about micronutrients which are just as important? First meal is much richer with omega 3 fatty acids (mainly EPA) also we get carbohydrates from starch of home-grown potatoes which grows on fertile soil and therefore contains minerals such as potassium, calcium, phosphorus and iron. However if we are lucky enough commercial fries are grown in mineral weakened soil or a even in "tubes". Oils such as coconut also contain Lauric acid which our body needs urgently. Overheated sunflower oil (due to heat) changes those omega 6 and change it into mostly saturated fatty acids which our body don't know how to use. We don't need to talk about the chemicals they use as pesticides and for the cultivation of animals, right? 

Do you still think that calories are equivalent? Would you rather take care of the optimal functioning of your organism at the cellular level?