How the body creates a balance
Diet can regulate the acid-base balance
Regulation of the acid-base balance is necessary to stabilise the pH of the blood. Many factors play a role here. The main factor regulating the acid-base balance is nutrients from our diet, and whether they are metabolised as acidic or alkaline. But also when we breathe or are physically active, acid is produced as a waste product of energy release in the cells and impacts the pH value of the blood. To avoid excess acidity overall, various regulation processes occur automatically in the body.
The body’s regulation options
Our body is provided with an efficient buffer system and can thus regulate the acid-base balance. Buffers are protective systems to avoid the pH values in body fluids and cells getting out of balance, primarily by stabilising the pH of the blood. Important components of this buffer system to regulate the acid-base balance are the alkaline bicarbonate dissolved in the blood and the red blood pigment haemoglobin. Bicarbonate can bind to acid and produce carbonic acid, which is metabolised to water and carbon dioxide. The latter is breathed out via the lungs. Zinc is a cofactor of the enzyme carbonic anhydrase, which is partially responsible for the formation of bicarbonate and is therefore important in regulating acid-base balance. The buffer systems and the stabilisation of blood pH mean that excess acid does not cause any damage initially.
The bicarbonate dissolved in the blood can bind to acid. It produces carbonic acid, which breaks down into water and carbon dioxide. Carbon dioxide is breathed out via the lungs. This means the blood’s pH value can be corrected quickly and effectively. Bicarbonate buffers regulate the acid-base balance. These need to be regenerated constantly by the supply of alkaline mineral compounds through the diet.
The most important organs that regulate the acid-base balance are the kidneys and lungs. The kidneys are the only organ that can excrete acid from the body directly. The lungs ensure stable pH values in the blood via respiration. The body can therefore regulate the acid-base balance by breathing out more carbon dioxide.
If the buffer system is pushed to its limits and if the kidneys’ ability to excrete acid is exhausted, the body has to bring acid “out of circulation” to maintain optimal metabolic conditions. By storing acid in connective tissue – whose physical properties make it particularly well suited for this – the body can regulate acid-base balance. The blood’s pH is stabilised as a result. But the connective tissue’s ability to bind to water decreases. The supply of the trace element copper can contribute to maintaining normal connective tissue.
To regulate acid-base balance, the body taps into its own alkaline deposits, the bones. The pH value of the blood can also be stabilised as a result. To counteract the acid load, alkaline minerals are released from the bones. If this condition lasts for a long time, the physiological balance between bone formation and resorption increasingly shifts, which results in the increased bone resorption. Intake of the minerals calcium and magnesium contributes to bone health.