Don't drink too little - and not too much
Adequate hydration is important for human health. But how much should we drink? And is it really true that increased fluid intake can improve performance, concentration and kidney function and detoxify it?
Half of the human body consists of water. It is essential for us and plays a central role in the organism, explains the Federal Center for Nutrition (BZfE) on its website. Those who drink too little risk health problems. But you can also overdo it.
Desirable drinking amount
At the latest when the thermometer rises to summer temperatures again, one remembers that sufficient drinking is important. As the BZfE explains, our organism only functions optimally when the water balance is balanced. From one to two percent loss of fluid, physical and mental performance decreases.
According to experts, a lack of water can lead to serious, sometimes irreparable damage to the organism. Too little fluid in the diet initially worsens the flow properties of the blood, breakdown products can no longer be excreted through the kidneys, muscles and brain are no longer optimally supplied with oxygen and nutrients. In the worst case, kidney and circulatory failure can occur.
But what is the desirable amount of drinking? For a healthy adult, around 1.5 liters per day are the minimum. With physical activity and / or high summer temperatures due to the increased sweating more.
The ideal thirst quencher and liquid supplier are above all water and unsweetened herbal and fruit teas. Juice spritzers with three parts water and one part juice are also suitable. Sugared drinks are not recommended according to the German Nutrition Society (DGE) because they often contain a lot of sugar and therefore unnecessary calories. This increases the risk of obesity, type 2 diabetes and tooth decay.
Modern food myths
Drinking a lot is good for body and mind, but you can also overdo it. As the BZfE writes, it is one of the modern nutritional myths that drinking a lot comes with numerous advantages, such as improved "detoxification", improved kidney function, increased performance, improved concentration, more beautiful skin and much more.
"But is a" MORE drinking ", defined as a hydration that goes beyond the coverage of the natural thirst sensation and the fluid intake associated with meals / snacks, really connected with positive effects?" Asks the BZfE.
The experts first make it clear that there can be no doubt that adequate hydration must be ensured in various situations. This includes above all the care of small children and also old people who cannot or do not want to drink enough fluids. As is well known, the feeling of thirst is reduced in old age, so that many seniors drink too little, or do not (want) to drink what they should.
Thirst regulates the necessary hydration
But how much drinking is ultimately healthy? Professor Wilfred Druml of the Department of Nephrology, Medical University of Vienna says: "The most common assumption that increased fluid intake and the associated increased urine volume lead to" flushing "and improved" detoxification "is wrong." The amount of urine is regulated hormonally. More water in the body only means more water and not more toxins.
Another basic assumption that an increased fluid intake by increasing the blood volume leads to an increase in the renal blood flow (improvement of the kidney function) is not correct. Whether, as is often claimed, a higher drinking amount leads to a reduction in energy consumption in patients with obesity (obesity) has not been clearly clarified.
There are certainly situations and diseases where an increased fluid intake is to be regarded as cheap. However, this does not apply to the healthy general population, says the scientist.
The fact of development history is that humans (like other mammals) are genetically adapted to a deficiency and can deal very well with “too little”, but badly with “too much”. This affects almost everything: energy, protein, salt and also water. The water balance is precisely regulated by an interaction of the organ systems brain (thirst center), skin and kidney regardless of the current fluid intake.
The feeling of thirst effectively regulates the necessary hydration. According to Druml, there is no scientific justification for "over-drinking", i.e. excessive hydration, improving a relevant physiological parameter in healthy people. (ad)
Author and source information
This text corresponds to the requirements of the medical literature, medical guidelines and current studies and has been checked by medical doctors.