Our body consists of about 45 to 70 percent water. The proportion depends on age, gender, body weight, fat and muscle mass.
A lot of chemical reactions take place in our body, and our body needs water for them every time. Water is also essential for the transport of nutrients and heat regulation. Water is also important for the excretion of metabolic products via the kidneys and for digestion.
In an adult, around 6 percent of the total water content is used in the body every day. The guideline for the recommended water intake for adults is 1 milliliter per kilocalorie. A less sporty adult needs around 2.5 liters of water a day. Around 60 percent of this must be consumed through drinks, the other 40 percent is consumed with solid food or is produced during metabolism.
Water is vital for our body's survival. A lack of water impairs physical and mental performance and, in serious cases, can also have other health consequences. After just 2 to 4 days without water, the body can no longer excrete substances that need to be excreted in the urine.
It is becoming increasingly common these days to see many people who are mentally active not drinking enough fluids, for example by not eating breakfast and forgetting to drink or no longer noticing the feeling of thirst. Those affected have reduced attention span, slower thinking, are less flexible and their memory performance is greatly reduced.
More and more people are not drinking enough at work. This results in a reduced ability to work, which is caused by a higher error rate and even an increased risk of accidents when not drinking enough fluids. One study found that simply installing a water dispenser in the workplace resulted in workers having a higher fluid intake and fatigue being slower.
If a person consumes less energy through food and therefore possibly less than their actual needs, the body produces more substances that have to be excreted in the urine. The result is that the body needs more water to excrete these substances. This means that people who are on a diet in particular absolutely need to drink more.
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