Without water, nothing functions in the human body. Learn how much water you should drink per day to stay well hydrated and what rules you can follow to easily keep your water balance under control.
Table of contents
1. Why is water so important?
Water is involved in a variety of bodily processes . It is stored as a component of cell structures , but it is also used as a transport substance in the blood .
It protects the joints and keeps the skin supple . Water transports waste products , vital nutrients , and, last but not least, helps us regulate our body temperature .
The water content of a healthy adult body is therefore approximately 50 to 60% . We consume up to 3 liters of water throughout the day .
This occurs primarily through the skin, respiratory tract, and kidneys. Since our body constantly consumes water , we must continually replenish fluids .
2. How much water a day - rules and formulas
The German Medical Association recommends a minimum amount of 1.5 to 2 liters of water per day for adults. International research, however, recommends a rule of thumb of approximately 30 to 40 ml of water per kg of body weight . This amounts to approximately 2 to 3 liters of water [1].
According to nutritionists at the MAYO Clinic, you can also calculate your water needs quite precisely . The rule of thumb is: weight in kg x age ÷ 28.3 .
Depending on your specific data, the result should be roughly in the same range as the rule of thumb [2]. Age is often an underestimated factor .
As we age, we automatically need significantly more water to prevent the wear and tear of joints, cartilage and other important parts of the body.
3. When your water needs increase
Essentially, the rule of thumb already shows this: Your water needs increase as you get heavier or older. However, this happens more gradually over the course of your life and training.
In general, you can also remember that your water needs always increase when your body loses water. And this happens especially when you sweat!
In summer , or before , during , and after training, your body needs significantly more water than usual. Your body also loses a lot of fluid when you have feverish illnesses or gastrointestinal problems, so you can support your body's regeneration with an extra portion of water .
Pregnant and breastfeeding women also need significantly more water . Furthermore, some beverages such as alcohol , coffee, or black tea have a dehydrating effect .
So if you enjoy consuming such drinks regularly, you should always give your body one or two glasses of water afterward.
4. What happens if there is a water shortage?
Mild dehydration can also occur in everyday life. It happens especially quickly if you're on the go a lot or simply don't pay attention to how much you drink. You'll then notice the dehydration through fatigue , lack of motivation , or dry skin, among other things [3].
In midsummer, staying in the sun at the same time can even put you at risk of heatstroke or circulatory collapse. In severe cases or with prolonged dehydration, it can even lead to cardiac arrhythmia.
But don't worry: Severe dehydration doesn't develop quickly . And if you notice any of these signs, you should simply drink more. Mild dehydration usually goes away on its own with adequate fluid intake.
5. Which drinks are best for hydration?
Fresh water is, of course, the best drink ! Lemonades, soft drinks, and juices often contain sugar and unnecessary calories. Nobody needs that. For those who want something a little more flavorful, spritzers are a suitable alternative.
Unsweetened herbal teas are also good for hydrating . They warm you up in winter, and in summer, they cool you down slightly and help regulate your body temperature.
Another great alternative to regular tap water is infused water : Simply add some fresh fruit to the water and wait 20 minutes. This way, the water takes on a fruity flavor and often even gains a bit of vitamin power.
BRAINEFFECT HACK : When you sweat a lot, you not only lose fluids but also important minerals. You can replenish these with electrolyte drinks. We developed our electrolyte drink RECHARGE for athletes and high performers.
It not only contains new minerals that you have just sweated out, but also amino acids for your muscles.
6. Water intoxication - How much is too much to drink?
Yes, there is also a type of water poisoning. In what is known as " intoxication ," the excess water can no longer be eliminated through the kidneys.
This can lead to overhydration in the long term, which can lead to, among other things, severe stomach problems and altered mental status. However, under normal circumstances, you don't need to worry about this.
To experience serious water intoxication, you would need to drink more than 10 liters of water a day . In the worst case scenario, this would only occur during a super-intense marathon [4].
7. Conclusion
Almost all vital functions in our body require water. Therefore, you should pay particular attention to consuming sufficient fluids every day.
The rule of thumb is that most of us should drink about 2 to 3 liters of water a day. If it gets particularly hot in summer, you have a dehydrating illness, or your workout was really sweaty, you should replenish your water.
This will optimally support your body's recovery. However, if you feel tired, exhausted, and lacking concentration, you should also reach for a glass of water.
Sometimes, a lack of motivation and performance problems can be caused by a slight dehydration. Although there are numerous soft drinks and refreshing beverages available, tap or mineral water is still the best thirst quencher.
Simple alternatives include sugar-free herbal teas or infused water. For particularly active individuals and athletes, water-soluble powder mixes with electrolytes are also suitable.
8. Sources
[1] Meinders, A.-J.; Meinders, A. (2010) How much water do we really need to drink, Nederlands Tijdschrift vor Geneeskunde, Volume 154, p. 1757, https://pubmed.ncbi.nlm.nih.gov/20356431/.
[2] Blake, I. (2017), How much you should REALLY drink in a day revealed, https://www.dailymail.co.uk/femail/food/article-4617270/How-water-REALLY-drink-day-revealed.html.
[3] Taylor, K.; Jones, EB (2020), Adult Dehydration, StatPearls, online access: https://www.ncbi.nlm.nih.gov/books/NBK555956/.
[4] Yonemura, K.; Hishida, A.; [...]; Ohishi, K. (1987), Water Intoxication due to Excessive Water Intake: Observation of Initiation Stage, Japanese Journal of Medicine, Volume 26, Issue 2, p. 249-252, https://www.jstage.jst.go.jp/article/internalmedicine1962/26/2/26_2_249/_article.
