Food and nutrients

The role of nutrients

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Hydration, circulation and cleaning

Water has a vital role to play. It:

  • Is the body's basic component 
  • Plays a role in several chemical reactions
  • Contributes to keeping a constant body temperature (thermal regulation)
  • Is used for carrying various elements around the body (circulation)
  • Allows waste to be eliminated in urine (cleaning)

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Hydration, circulation and cleaning

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Every nutrient plays a specific role in the body and each is vital for health. This is also true of water. Water does not provide energy but is the main component of the human body and is found in all cells. We refer to intracellular water to mean the water contained in cells and extracellular water to refer to the water that surrounds cells. On average, water represents 60% of body weight, but this proportion depends on age, weight and size. The thinner a person is, the higher the percentage of water. However, this proportion diminishes with age since body tissue dehydrates with age.


Some people compare the body to a sponge which needs to be constantly soaked to ensure it does not dehydrate. The body constantly loses water through perspiration, excretion and even breathing. Although we can store energy, we cannot store water. This means that any loss of water has to be replaced by new supplies every day. Which is why we cannot survive very long without water. You cannot go without water for more than 2 to 5 days, as a loss of 20% of the water in the body can be fatal.


The role of water does not stop there. It takes part in numerous chemical reactions. It therefore plays an important role in body function. It also helps to keep body temperature constant via perspiration.

Keywords > Circulation

Water carries blood cells and nutrients. It carries the substances our cells need, such as vitamins and minerals, inside our cells.

Finally it helps clean the body by helping the kidneys eliminate waste through urine.

In summary, water can be considered as a separate substance. This substance is the main component of the human body and allows it to function. This 'multi-purpose' substance regulates, transports and cleans. This substance is so ordinary we sometimes forget just how important it is.

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