Water how much should we drink

Our organism consists of more than 70 % of water. A lack of water (= dehydration/desiccation) leads to serious health problems in humans.

In this case, the functions of the body that depend on water are restricted. Already 0.5 % of water deficiency causes thirst.

The effects of water deficiency

2% of water deficiency impair performance. Muscle cramps, headaches, nausea and loss of appetite are further consequences. From a water deficiency of 5 % the blood flow is impaired (the risk of thrombosis in the blood vessels increases).

10% of water deficiency results in disorientation, dizziness, and weakness. Water deficiency above 10% leads to death.

How much should a person drink per day?

Boy drinks water
Daily water consumption of 2.5 liters is recommended

As far as daily water needs are concerned, many recommendations outperform each other. Some recommend several liters a day. This is completely unfounded because excessively high drinking quantities have no demonstrable advantages for the organism.

Excess water is excreted via the kidneys, the excretion quantity increases and the urine is thus less concentrated. This means that there is no more efficient “detoxification”. Under normal conditions, water consumption of about 2.5 liters per day is recommended.

Starting from approx. 300 ml oxidation water, which is produced in the body during combustion processes (combustion of fatty acids and glucose), and from approx. 700 ml water, which is ingested with solid food, approx. 1.5 liters still have to be drunk in order to balance the liquid balance. During physical work (e.g. sporting activities) and hot temperatures, the daily water requirement can increase by a factor of 3 to 4, in extreme situations by more than 10 leter.

Gelten caffeine and alcohol as a drink?

Contrary to the still prevailing opinion that caffeine and alcohol remove water from the organism, caffeine-containing drinks such as coffee and tea should also be included in the fluid balance because they only have a diuretic effect for a short time.

If you like, you can drink a glass of water with your coffee. With moderate consumption, alcoholic beverages such as beer should also be included in the fluid balance, especially as alcohol only has a short-term diuretic effect in higher doses.

In a healthy person, high water consumption favors the work of the kidneys and the circulatory system. However, excessive drinking of large quantities of water (more than 20 L/day) can also lead to health problems.


This post is also available in: German

William C. Hilberg
As an author, Mr. Hilberg has published several papers on health issues that have gained international recognition. He is close to nature and loves the seclusion and activity as a freelance journalist. In his function as editor William C. Hilberg manages the entire content of PENP. Our team greatly appreciates his expertise and is proud to have him on board.