How often should you drink water and what is water balance. Water balance: how and why to maintain it? The water balance of the body and its types

AT human body in the process of evolution, a complex mechanism was developed that provides normal water balance - the amount of water consumed should be equal to its consumption. The water balance in a person is calculated by the daily consumption of water, as well as its excretion from the body. A person receives an average of 2.5 liters of water per day: 1.2 liters - due to the liquid he drinks, 1 liter - together with food products that contain water, 0.3 liters of water is formed in the body itself during metabolism - this is the so-called endogenous water. The same amount of fluid in 24 hours must be removed from the body.


An adult needs 2.5-3 liters of water per day - as part of food and drinking, because. approximately this amount of water is lost to the external environment. If the temperature of the external environment is equal to the temperature of the human body, then an adult evaporates 4.5 liters of water daily.


The demand for water varies significantly with temperature. environment, on the nature of nutrition and in particular on the salt content in food. For example, when working in a hot climate, the total daily requirement for water in food and drinking increases to 10 liters.


Water is formed, in addition, in the body itself during the oxidation of nutrients. In large quantities, it is found in some foods, for example, in vegetables, berries, fruits. With complete oxidation per 100 g of a substance, water is formed: during the oxidation of protein - 41 cm3, starch - 55 cm3, fat - 107 cm3.



For every 420 J released during the breakdown of organic substances, 12 cm3 of water is formed, about 300 cm3 per day. On average, in the body of an adult per day enters drinking water 1200 cm3, and contained in food - 1000 cm3. About 1.5 liters per day is excreted from the body of an adult with urine, 100-200 cm3 with feces, 500 cm3 through the skin and 350-400 cm3 through the lungs. This is how water balance is maintained.


With a lack of water in the body, a feeling of thirst appears, which is expressed by a peculiar sensation of dryness in the oral cavity and pharynx. The center that regulates water metabolism is located in the brain stem. The main cause of thirst is a violation of the optimal ratios between water, salts and organic substances in the blood, resulting in an increase in the osmotic pressure of the body fluid.


Drinking regime - rational order of water consumption. Properly established drinking regimen provides a normal water-salt balance and creates favorable conditions for the vital activity of the organism. Chaotic, excessive drinking impairs digestion, creates an additional burden on cardiovascular system and kidneys, leads to an increase in the excretion through the kidneys and sweat glands of a number of substances valuable for the body (for example, table salt). Even a temporary load of water disrupts the working conditions of the muscles, leads to rapid fatigue, and sometimes causes convulsions. Insufficient water intake also disrupts the normal functioning of the body: body weight drops, blood viscosity increases, body temperature rises, pulse and breathing become more frequent, thirst and nausea appear, and efficiency decreases.


The minimum amount of water required to maintain the water-salt balance during the day (drinking norm) depends on climatic conditions, as well as the nature and severity of the work performed. For example, for temperate latitudes, the amount of water administered with drinking and food with minimal physical activity is 2.5 liters per day, with moderate physical work up to 4 liters, in the climate of Central Asia with a minimum physical activity of 3.5 liters, with physical work of moderate severity up to 5 liters, with heavy work in the open air up to 6.5 liters.


It is especially important to observe the correct drinking regime in conditions that cause large losses of fluid by the body, which often occurs in hot climates, when working in hot shops, during prolonged and significant physical exertion (for example, during training and competitions, mountain climbing). Residents of areas with a hot climate are advised to completely quench their thirst only after saturation and strictly limit fluid intake between meals. To quench thirst, tea is used, which increases salivation and eliminates dry mouth, fruit and vegetable juices or extracts. In hot workshops, they drink sparkling water or decoctions of dried fruits. The drinking regimen of athletes provides for quenching thirst after the end of the exercises. When mountain climbing, it is recommended to quench your thirst only during large halts. With significant weight loss associated with heavy physical exertion (after training, sports competitions, steam baths), it is recommended to drink fractional portions.

Debunking myths about drinking water

Every day you need to drink 2 liters of water. Is this a myth or true? We tell you how much water each of us really needs, why maintain water balance and how it affects our well-being and appearance.

We all know that the human body is mostly water (if we are talking about an adult, the proportion of water is approximately 60%). Based on this, it is not difficult to understand why drinking water is vital. We must maintain the amount of water in the body necessary for vital activity - that is, maintain the water balance. This, however, is not easy for everyone - many people find it difficult to drink in a day a large number of water. In addition, some prefer other drinks and drink little pure water. What to do in such a situation?

1. Understand how much water the body really needs. The statement that everyone should drink at least 2 liters of water daily is considered almost an axiom. In fact, as experts have been saying for years, this is a myth. There is a version that it spread after the publication of the recommendation of the National Council on Food and Nutrition of the United States in 1945, which stated that, according to the norm, adults should drink 2.5 liters of water per day. However, there is no scientific justification behind this figure - there are still no studies that would confirm that exactly 2.5 liters (or the same 2 liters) of water per day is the norm. It is also necessary to take into account the fact that the needs of organisms may vary depending on the age of a person, his weight, his lifestyle, and so on.

Thus, it is more expedient to calculate the individual rate of daily water consumption. How? Very simple! It is believed that women need 30 ml of water for every kg of weight, men - 35 ml. Thus, you just need to multiply your weight by a suitable indicator. The resulting number as a whole will reflect your need for water.


The calculation, however, will be more accurate if you also take into account your daily activity. This is possible using another formula (weight - in kg, activity - in hours):

(weight x 0.03) + (daily activity x 0.4) = norm for women

(weight x 0.04) + (daily activity x 0.6) = norm for men

2. Find out what, besides drinking pure water, helps to maintain water balance. These are, firstly, such healthy drinks as tea, milk and kefir, natural smoothies and juices - they all contain water and contribute to the replenishment of water reserves in the body. Secondly, solid foods can also saturate the body with moisture. It turns out that many of them are more than half water. These are some vegetables (for example, cucumbers, tomatoes, pumpkin), fruits (orange, grapefruit, apples), rice and other cereals.

But since it is almost impossible to control how much water enters the body with food and various drinks, it is better not to forget to drink pure water. It’s okay if you can’t always fulfill your personal norm. The main thing is to listen to your body, which will always let you know that it needs water. Are you thirsty? Drink some water! Pour yourself a glass when you have a free moment - it will refresh and help prevent the feeling of thirst.

To make it even easier for you to keep your water balance day after day, follow a few simple tips:

Make sure you have water in front of you and at your fingertips. To the bottle, which is a few centimeters from you on the desktop, you will probably reach out yourself.

Drink water through a straw. Thanks to this, the sips you take will be larger, and you will empty your bottle much faster.

If you do not like the bland taste of water, throw a slice of lemon, lime or orange, mint leaf into a glass.

To get used to drinking water, try betting with friends and colleagues who can stick to their water intake for longer.

Install an application on your smartphone or tablet that helps you keep track of your water balance.


There can be no doubt that water is life. Each of us needs water to stay hydrated, but we must not go to extremes in this pursuit and let the myths fool us. Drink water and be healthy!

February 19, 2016, 11:12 2016-02-19

Usually need for water an adult living in a non-hot climate is at least 2.5-3 liters per day (in a tropical climate, the need more than doubles). Approximately half of this volume comes from a variety of drinks and another half - from food, and is also formed as a result of the breakdown of organic matter (such water is sometimes called "metabolic"). On average, a person excretes about 1.4 liters of water per day with urine and about 1 liter evaporates from the surface of the body, as well as from the lungs. Thus, the water balance of the body is maintained - equilibrium between the amount of water entering the body and what is excreted.

It should be taken into account that the need for water depends on vital activity, nutrition, physical activity, health, age, climate and even weather.

Not everything that is called water in everyday life is safe for human health. So, for example, tap water treated with chlorine, containing harmful ions, and in which pathogenic organisms and harmful substances are found, is not at all suitable. The best water for drinking is considered to be water from natural sources, which contains a balanced complex of various ions, has the surface tension and oxygen saturation necessary for the body.

water scarcity in the body - chronic dehydration- one of the causes of many diseases (asthma, allergies, high blood pressure, overweight and even mental disorders, such as depression). Usually people do not feel that their body is deficient in water.

It turns out that most people daily drink less liquid than is necessary for healthy life. And their illnesses are in no way associated with a lack of water - the main solvent, without which life is impossible.

It follows from the above that drinking water will soon become an important natural resource that will determine the health of the nation. While already now in Ukraine it is one of the most scarce natural resources. Due to the physical and geographical features of the territory and due to the creation of a huge number of dams that blocked the rivers and led to their pollution, Ukraine has become a country with a constant shortage of drinking water. Every year, each inhabitant of our country accounts for up to 1 thousand m3 fresh water in year. Whereas, according to UN estimates, an order of magnitude more is considered sufficient - 10-15 thousand m3.

Some more interesting and important information. With a loss of water by 2% of body weight, thirst appears, by 6-8%, semi-consciousness occurs, with a shortage of 10%, hallucinations appear, and with a deficit of 12%, a person dies.

Smoking leads to dehydration.

Drinking coffee and alcohol also leads to dehydration. For every cup of coffee or alcohol you drink, you should drink an additional glass of water.

If an athlete drinks more water than the feeling of thirst requires, then his endurance increases dramatically.

Those who drink more water and drinks show more endurance, and such people are also prone to creativity.

Many of those who want to lose weight believe that their body retains water and try to drink as little as possible. However, water is a natural diuretic, and therefore, you should drink more water when losing weight.

When traveling, a person often encounters digestive problems and fatigue that are difficult to explain. It turns out that their cause is only a change of water. The fact is that the body "remembers" a certain balance of substances in the water consumed daily, and reacts to changes in this composition.

Water is of particular importance in the body - the most massive cell compound and the most common substance on planet Earth. It has small polar molecules and semi-crystalline structure. This is the only substance that can be in three states of aggregation. Water is a strong solvent and chemically active substance. It ensures the body's thermoregulation, transportation of substances in the body, the movement of blood by capillaries in animals and water by leading vessels in plants.

Text: Anton and Olga
Photo: Olga

Today we will raise a very important topic - the body's water balance, problems with it and how to avoid these problems.


general information
The human body, depending on age, consists of 90-50% water. Of them:


  • Blood - 92% water,

  • muscles - 75% water,

  • bones - 22% water,

  • gastric juice - 99% water,

  • adipose tissue - 20% water,

  • the brain is 85% water.

At the same time, serious consequences can occur with a decrease in water reserves in the body by only 2% (deterioration of well-being, weakening of short-term memory, difficulty concentrating), and a loss of 4% leads to a weakening of muscle function, 5% causes a sharp decline in strength, 7% loss - hallucinations, 10% - acute vascular insufficiency (heat stroke). This is due to the fact that water is needed by the body for cooling (through sweat). It is also important to remove electrolytes from the body along with sweat, the deficiency of which adversely affects the functioning of the joints.

In biology, electrolytes are aqueous solutions containing various ions (cations - sodium, potassium, calcium, magnesium; anions - chlorine, bicarbonate, phosphates, sulfate). Electrolytes are necessary for the body, they are responsible for the osmolarity of fluids in the body, have immunotropic activity, serve as an “energy reserve”, participate in blood clotting, form a bioelectric potential, catalyze metabolism, determine the activity of hydrogen ions (pH) of body fluids, affect the condition of bone tissue.

Daily water intake and electrolyte recovery
Given the importance of water in the body, it is imperative to monitor your own water balance (as well as acid-base balance), especially with increased physical exertion. The minimum daily water intake for an adult is 1.5 liters, while water consumption, which gives an increased load on the kidneys and the cardiovascular system, must be calculated individually (for increased physical exertion, the daily intake is calculated at the rate of 40 ml / 1 kg of body weight, more burden the kidneys and heart).

Acid-base balance (ABB) is the acid-base ratio in the body. Is an integral part homeostasis, that is, directly related to the body's ability to maintain life. Changes in acid-base balance affect the quality of chemical reactions in the body, which can be extremely dangerous for health.

It is very important to maintain (maintain) the acid-base balance (ACB) in the body. To date, there are a lot of tablets and solutions to maintain the KSB. One of the most affordable means is Regidron, which is used in medicine to restore the KSB during vomiting and diarrhea. After dissolving 1 sachet in 1 liter of water, you need to drink about 10 ml / 1 kg of body weight to restore the BCH, or 1 sachet / 24 hours to maintain the BCH.

Please note that in case of severe dehydration (10% or more), drugs such as "Regidron" are ineffective, rehydration (restoration of the amount of water in the body) must be performed by intravenous means with careful monitoring of CLB (i.e. in a hospital setting).

For high physical exertion, the system used in sports is effective: 500 ml before exercise, one or two small sips every 15-20 minutes during exercise, 500 ml after exercise (solutions / isotonics can be used). Such a system goes very well with.
It is very important to remember that the body reacts painfully to changes in water and acid-base balance. Even small changes seriously affect muscle tone and, ultimately, physical fitness in general.

Useful facts and tips


  • You can’t treat water according to the principle “I’m reluctant to drink now”, “I will endure until the halt”, etc. It is necessary to strictly adhere to the chosen scheme for maintaining water balance;

  • caffeine interferes with the restoration of water balance in the body;

  • during bouts of hunger, taking a portion of water will change the mood “would eat a horse” to “now I would have a bite to eat”;

  • the intake of chilled water leads to a slowdown in metabolic processes, so it is worth drinking water, conditionally “room” temperature;

  • "Regular" water is not able to restore the ASF, because it causes a rapid drop in the osmotic pressure of the blood plasma and dulls the feeling of thirst before the fluid reserves are fully restored. Therefore, it is advisable to use special solutions / isotonics or tablets;

  • all kinds of "tricks" such as a pebble (or even a bullet) under the tongue are unacceptable, it is impossible to fight the feeling of thirst;

  • it is unacceptable to use fruits instead of water (oranges and especially lemons) or large amounts of tea (many brew green tea) to maintain water balance, you can greatly harm your stomach in the case of fruits (due to exposure to citric acid on the stomach) or exacerbate water loss by the effects of caffeine (caffeine has diuretic properties, and besides, “encourages” the consumption of electrolytes).

Examples of water balance control
For hiking, you can offer the following option:
As a basis, we take 3 l / day. At the starting point, we get drunk (500 ml), during the day route we take one or two sips every 20 minutes (about a liter per route), when we stop for the night, we drink 500 ml of water with a solution / tablets (or isotonic) for maintenance of the CLB. The remaining liter can be taken both in the form of "soup and tea", and again drunk "to your fill".
There are also a large number of options with detailed calculations (based on body weight) from “back to back” to “full recovery” *.

*For more information on intake rates, see Daily Water Intake and Electrolyte Recovery.

Dehydration (dehydration), its symptoms and first aid with dehydration
Dehydration (dehydration) is pathological condition organism, caused by a decrease in the content of water in it, accompanied by metabolic disorders. The cause of dehydration can be a number of diseases associated with significant water losses (sweating, vomiting, diuresis, diarrhea), or insufficient intake of water in the body.
Symptoms of dehydration: intense thirst, dry mouth/sticky saliva, small amount of urine, dark yellow urine, feeling unwell, weakness, loss of concentration, apathy. With severe dehydration - hallucinations, acute vascular insufficiency (heat stroke). Dehydration of 10-20% is life-threatening.
First aid for dehydration


  1. The victim must be urgently removed from the open sun into the shade.

  2. It is necessary to normalize body temperature (unfasten clothes on the victim, cool with compresses, etc.).

  3. Give water to drink (small sips) or a special solution / isotonic. Water with salt tablets or with salt sprinkled on the tongue may work.

  4. Observe the victim to determine the severity of dehydration. If necessary, take to a doctor (for inpatient treatment).