It is called ATP and it is the molecule, or rather, the currency that we spend for the circulation of the energy necessary to live.
In every moment of our life, a healthy body contains only about 250 grams of ATP as a stable deposit.
But, the incredible fact is that every day a person on average produces about two hundred trillion trillion molecules of ATP, which corresponds to about 80 kilos. This means that the equivalent of a body mass of 80 kilos in ATP is produced and recycled every day!
Together these molecules meet our metabolic needs at the rate of 90 Watts, which is the minimum to stay alive and feed the body.
ATP is produced by the mitochondria.
Each mitochondrion contains approximately between 500 and 1000 respiratory complexes and we have approximately between 500 and 1000 mitochondria inside each cell, depending on the type of cell and its energy needs. Muscles need a lot of energy, so their cells are full of mitochondria, while fat cells, for example, have much less. On average, each cell in our body can possess, distributed among its mitochondria, up to a million of these small motors that are the respiratory complexes, which work day and night to produce that astronomical number of ATP that keeps us alive, healthy and strong. The rate at which the total number of these molecules are produced is a measure of our metabolic rate.