Basic Knowledge Oxygen
Oxygen is vital for us, with its share of approx. 21 % in the air. Since oxygen cannot be stored by the body, we have to breathe continuously. Oxygen occurs in nature mainly as a molecule of two atoms (O2). Our body cannot absorb 75 % of the oxygen we breathe in from the air; only 25 % of the oxygen from the air is absorbed and used under optimal conditions.
- The air has an oxygen content of approx. 21%
- Approx. 5.25% is absorbed by the body under optimal conditions and bound to haemoglobin (= 1/4)
- Approx. 15.75% are exhaled unused (= 3/4)
How much oxygen is usable by the cells and organs in the body?
- 98% oxygen in arterial blood bound to haemoglobin is normal. About 20.4 ml/dl in men and about 18.8 ml/dl in women
- Only about 5 ml/dl is used in the body by the cells and organs. This is the difference between arterial and venous oxygen saturation
- This means: A maximum of 25 % of the available oxygen is used in the body by the cells, organs and tissues
Oxygen and its energy states
Oxygen can be inert or reactive depending on the energy level. An example clarifies the concept of what inert and reactive means: chemically, water is always H2O – whether it is warm or cold. Sugar or salt is known to dissolve better in warm water than in cold water. Warm water has a higher energy state than cold water. In the same way, oxygen can also be inert and reactive.
The oxygen in the air around us is inert (triplet oxygen = 3O2) and must be continually activated by the body itself in order to become reactive (singlet oxygen = 1O2) so that it can form chemical compounds at all.
Energy production in the body through oxygen
Except in emergencies, in intensive care or in severe lung diseases such as COPD, pulmonary fibrosis, pulmonary emphysema or pulmonary sarcosis, sufficient oxygen usually reaches the blood from the air via the lungs (=external respiration). This can be measured very easily with a so-called pulse oximeter (finger clip). Values of 96% to 98% are a sign that oxygen is sufficiently saturated in the blood. An increased supply of oxygen therefore makes no biological sense here, as the blood is already saturated to the maximum with oxygen.
The cause of many disorders lies in the utilisation of oxygen within the cells in the mitochondria. If the actual combustion process no longer runs optimally, less energy (ATP = adenosine triphosphate) is produced, just like in a car engine, and at the same time more harmful substances (free radicals) are produced and the lifespan of the cells/mitochondria decreases.
Supplying the body with more oxygen is not the solution! If the engine of a car is badly adjusted, it makes no sense to pour more petrol into the tank. The engine, especially the combustion processes, must function optimally again.