A matter of survival: Water
Water makes up at least 60% of an adult’s body and not a single cell in the body can function without it. Every day, a certain amount of water leaves the body through urine, sweat and exhaled air. If this loss is not compensated, it leads to a decrease in blood volume, since blood is 90% water. This in turn leads to low blood pressure and to the fact that our body stops sweating. However, since sweating is our body’s mechanism against overheating, as a result the body temperature rises until it reaches a critical point.
A healthy person can theoretically go a week without water in cool weather, in practice it is actually usually only 3-4 days!
Under extreme circumstances, such as intense heat or during extreme sports, the body loses as much as 1-1.5 liters of sweat per hour. Without replenishing this lost body fluid immediately, a person would even die within a few hours!
Symptoms of dehydration
Dehydration occurs when our cells and organs use more fluid than our body takes in. Our body gives some signs to drink water as quickly as possible to prevent dehydration:
- Increased thirst
- Dry mouth & chapped lips
- Fatigue & weakness
- Headache
- Dizziness
- Urine that is dark yellow in color
- Decrease in the amount of urine
- Chronic constipation
- Kidney pain
- Muscle cramps up to heavy seizures
Already at 10% loss of body fluid we reach a critical state of health, which is manifested by extreme physical conditions.
Daily drinking amount
Under normal conditions, the body of an adult loses 2 – 2.5 litres of water every day: through urine, skin, breath and digestion. Depending on the situation, we also lose significantly more fluid: in high temperatures, sports or stress, water loss is much higher. (Small) children and breastfeeding women also need more water than others. In addition, everyone has their own specific metabolism and eating habits. By the way, when sweat flows, water loss can be up to one litre per hour.
As a rule of thumb:
- If we assume that we lose about 2.5 litres of fluid per day, we should also replenish this amount.
- We take in about 1 litre of fluid through solid food.
- The remaining one and a half litres should be drunk.
- But here, too, it is better to drink a little more than too little. If necessary, the kidneys (in healthy people) will excrete the excess moisture without any problems.
