My today’s post is about water. Water is a remarkable substance. It is shapeless and transparent, though mandatory for all life on Earth. Most people disregard the importance of water since it is ubiquitous – at least in the industrial world.
Water – a unique substance
The extraordinary features of water derive mostly from its dipole-structure and its capability to form hydrogen bonds. Its unique feature is that its volume decreases while cooling down until it reaches a temperature of 4°C. However, if its temperature decreases further, its volume increases again. This sounds paradoxic but is essential for life, particularly in water environments. Why is this so?
The increasing volume while freezing causes a density decrease. The density of ice is lower than that of liquid water which makes ice blocks swim on the water surface. If this was not the case, ice blocks would sink to the ground and oceans and lakes would freeze from the ground to the surface. Some would probably never thaw again and life could not exist in such environments.
The water in our body
Water plays an important role in biochemical and physiological processes. Our body consists of approximately 60% of water. The body of babies consists of higher amounts, up to 80% while elderly people’s bodies are only made of around 40-50%.
The water content of fat-free tissues is around 70% while fat contains only 10-40%. This explains why overweight people’s bodies are made of less water than the bodies of muscular people.
The water balance
We take water in through food and beverages and we eliminate water through urine, stool, the skin and breath. Our body is even capable to produce some water. Did you know that? An aduld produces approximately 350 ml of water a day through metabolic processes. For instance, water is a by-product of the respiratory chain where energy (ATP) is produced. But our body needs more water:
To be able to eliminate toxic and unusable products through the kidneys our body requires at least 650-700 ml of water per day.
150-200 ml of water leave or body via stool per day.
Approximately 350 ml of water evaporate through our skin per day.
100-350 ml of water are exuded through sweat.
And we finally eliminate approximately 500 ml of water through our breath.
If our water balance gets negative we are likely to suffer from headaches, fatigue, nausea and vertigo. Muscle cramps, dizziness, absence and collapse are then potentially life-threatening consequences.
All in all we use up and eliminate approximately 5-6% of our entire body water per day. This means that we need to drink at least 2-3 litres to be able to compensate this loss. Of course, if you are very active, you lose even more water per day that needs to be replaced somehow.
So, I hope that this post makes you more aware of the importance of water in our nutrition.
Take care