Hyperacidity – does it really exist?

Protein-rich foods such as meat, sausage or eggs form acids when broken down in the body. Sugar and coffee are also acid-forming foods, while fruits and vegetables are considered basic. Many naturopaths believe that eating too many acidic foods is bad for your health. According to the theory, the acid-base balance is disturbed in many people and this in turn is the cause of many diseases.

However, nutritionists consider the classification of foods according to their acidic and alkaline effects to be superfluous. Because it is not that simple with the acids in the body: the metabolism constantly produces acids, even without eating, and has sophisticated buffer systems that keep the pH value in the body constant. “A healthy person does not become excessively acidic because this is precisely regulated by the organism,” explains Prof. Dr. Andreas Pfeiffer from the German Institute for Human Nutrition Potsdam-Rehbrücke (DIFE), who also works as a metabolism expert at the Berlin Charité , t-online.de.

Most body processes work best when the body fluid is neutral or slightly alkaline. Blood pH is kept slightly alkaline at around 7.4, while saliva and bile are nearly neutral with a pH of 7.1. The stomach, on the other hand, has an extremely acidic environment with a pH of 1.2 to 3.0. This is the only way protein digestion can work. Complicated buffer systems regulate the acid-base balance and thus ensure a smooth metabolism. “This works perfectly for healthy people — no matter what you ate before,” adds Pfeiffer. The pH value in the blood also changes only minimally.

The main role is played by the kidneys. It excretes excess acidic ions, which can be measured in “acidic” urine. However, this is not a sign of hyperacidity, but rather that the regulation is working properly. In this regard, test strips for measuring the pH value in urine, which are offered in pharmacies, are also not useful for measuring hyperacidity. The pH of urine varies significantly throughout the day and this is completely normal. The lungs are also heavily involved in regulating the body’s acid-base balance – they are used to remove acidic carbon dioxide (CO₂). If the kidneys or lungs are not working properly, the body can become acidic. Those affected are then ill and must be treated.

However, there are situations in which the acid-base balance is out of balance and life-threatening acidosis – or acidification of the blood – occurs. This can occur with diseases such as diabetes or kidney failure. The buffer systems of the body are then overloaded, causing the pH value in the blood to drop. Such over-acidification is manifested by particularly deep and rapid breathing and an acetone smell in the breath, reminiscent of overripe fruit. This hides serious kidney or lung diseases that must be treated causally. A healthy diet alone is usually not enough, but it can have a positive effect on the course of the disease.

Since hyperacidity does not exist, even acid-base diets are useless when it comes to acid-base balance. But they don’t do any harm either, as Dr. Pfeiffer: “Most of the components of these diets are healthy, plant-based foods like fruits and vegetables, so there’s nothing wrong with this diet.”

If you want to lose weight, you have to change your eating habits in the long term, eat a lot of fruit and vegetables and exercise enough.

(t-online, lk)