Published at: 05/10/2018

In an article we are going to look for an answer to the question - how much water is right and useful to drink per day.

The answer is strictly individual

How much water should you drink? Should you drink more water if you are doing sports? Do you drink enough water while you are doing sports? Do you drink more water than you should?

All these questions vary from person to person.


Water is vital to us and there is hardly anyone who can question this.

Water is not a macronutrient, but it is no less valuable to our health, so we need to keep our body hydrated at all times.

Approximately 60% of the total body weight is composed of water. This percentage is not a constant and can vary between different people according to their body composition.

Let’s give an example with two people with the same weight. The first one has lower percentage of fats and higher amount of muscles while the second one has more fats and less muscles. Theoretically, the first person should have more water in the body because the different cells contain a different amount of water.

Muscle cells contain 75% of water, blood - 83%, bones - 22%, fats - 25%.


Some of the functions of the water in the human body are:

(1) Transport functions: water transports nutrients to the cells and takes the waste products from them;

(2) Role of a catalyst in different chemical reactions;

(3) Joint lubricant;

(4) Body temperature controller. Have you ever wondered why we sweat? When the body temperature rises, we begin to sweat in order to cool the body;

(5) Protective function, protecting internal organs;

(6) Source of minerals.


Which factors affect the amount of water in the body?

For the normal functioning of the body, it is important for us to maintain fluid balance – the amount of fluids taken in should be equal to the amount of fluids taken out.

We lose water through urine, feces, sweating and exhaled air, and we receive water through the food we eat and the fluids we drink.


On average, the body of a healthy adult loses about 1500 ml of water through physiological processes and this loss can be increased by:

(1) Physical load;

(2) Warm / hot weather;

(3) Low humidity;

(4) High altitudes;

(5) Excessive consumption of beverages containing caffeine and alcohol.


When do we lose liquids?

(1) Through skin and breathing - about 800 ml

(2) Through the urine - about 500 ml

(3) By sweating - without training - about 100 milliliters

(4) Through faeces - about 100 milliliters


Many people, however, do not get enough fluids because they drink water when they feel thirst but thirst only occurs after 1-2% of the fluid level in the body has already been lost. Other people don’t feel thirst because they have taken fluids through food as well.


Why is it important to drink enough water?

In the world of the "healthy lifestyle", we often talk about dehydration and how dangerous it is, but there is actually one more disturbance in the water balance, which should also not be neglected.

This is why we are talking about optimal water supply - neither too little nor too high (adjusted to the needs of the individual).



Dehydration occurs when the loss of fluid is greater than its intake and the factors that may contribute to the dehydration are: vomiting, diarrhea, trauma, kidney problems, diabetes, fever, sweating, etc.

Dehydration reflects not only on the water balance but also on the electrolytic balance.


If the body loses 10% of its water reserves, the normal functioning of the body is impaired. Symptoms include:

(1) Confusion;

(2) Dizziness;

(3) Weakness;

(4) Muscle cramps;

(5) Exhaustion;

(6) Irregular heartbeat;

(7) Constipation.


Losing of 20 percent or more of the water supply leads to life-threatening symptoms, and if the loss is not stopped on time, a fatal outcome may also occur.

The body does not adapt to dehydration, so it is important that we do not wait to get thirsty in order to drink water.



Hyponatraemia is the other dangerous condition that is characterized by too much water intake compared to the sodium content of the body (this is important to be said).

The normal blood sodium concentration is between 136-145 mEq / L. Hyponatremia occurs when this concentration falls below 135 mEq / L.

There are three main types of hyponatraemia: hypovolemic, euvolemic and hypervolemic.

  • Hypovolemic hyponatraemia is associated with salt loss in the body and occurs when blood plasma, body fluids and sodium content fall;

  • Euvolemic hyponatraemia occurs when blood plasma and water content in the body increase, but sodium levels remain unchanged;

  • We have hypervolemic hyponatraemia when the blood plasma, the water and the sodium content in the body increase, but sodium levels do not increase in proportion to the water levels in the body.

Symptoms of hyponatraemia include: discomfort in the digestive tract, vomiting, headache, impairment of the brain and heart functions, dizziness.


How do I determine how much water I need?

This is not entire article. It continues ...