Updated 05 October 2015

Water and your body

Water plays many different roles in the body. Here are a few of the most important ones.


Body temperature

Water helps to regulate the temperature of our bodies through respiration and perspiration. This complex mechanism is controlled by the central nervous system.


In order to take in oxygen and eliminate carbon dioxide, our lungs must be moistened by water. We lose between half a litre and a litre of water every day just by breathing.


Brain tissue consists of 85% water, and with dehydration, the level of energy production in the brain decreases. Depression and chronic fatigue syndrome are often the result of dehydration.

Dehydration can also cause an increase in the body's internal temperature, which can lead to migraine.


Water lubricates our joints. When the cartilage is hydrated, the two opposing surfaces slide smoothly and the damage caused by friction is minimal. If the cartilage is dehydrated, the damage from abrasion increases, causing a deterioration of the joints.


The volume of water stored in the spinal column supports 75% of the weight of the body. The joints in the spinal column are dependent on the hydraulic properties of the water. Back pain is often relieved by hydration.


Our kidneys remove waste products such as urea and lactic acid, which must be dissolved in water. When there is not enough water, these waste products are not removed effectively and may cause damage to our kidneys.


Water helps to convey the nutrients through the baby's blood. Water also helps to prevent bladder and urinary tract infections, constipation and piles in the mother.

Correct hydration is essential for good milk production and for constant replacement of leaks of amniotic fluid. Dehydration could induce contractions and premature birth.

Weight loss

Water contains no calories and it helps to reduce the appetite and assist the body in metabolising fats. When you feel hungry, your body is often merely dehydrated.


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