Last Updated on 18th March 2019
Dr Noureen Ahmad
General Practitioner, Belgium
Water is an essential element of life. The Holy Quran states in Surah al-Anbiya: “Do not the disbelievers see that the heavens and the earth were (a) closed-up (mass), then We opened them out? And We made from water every living thing. Will they not then believe?” (Ch.21: V.31)
Over 70% of Planet Earth consists of water and is present in many forms such as liquids (rivers), gases (water vapour) and solids (icecaps).
Water can move from one form to another and from one place to another. The same thing occurs in our bodies. Our bodies contain about 60-70% of water and is present in many forms such as the air we breathe and the sweat from our skin. Sometimes the water percentage in the human body can differ, for instance babies and children have more water content in their bodies compared to adults. Men are more likely to have more water content than women.
Water has many functions in the body and dehydration or water shortage can lead to several symptoms and problems. The blood in our body exists of over 90% of water and this makes oxygen transport to body cells possible. It also aids in dissolving minerals and nutrients enabling them to be easily transported to organs.
Water plays a key role in maintaining blood pressure which is regulated by the water and salt balance in the body. At various places, such as big arteries, the heart and kidneys, there are pressure sensors which can sense alterations in blood pressure. When it drops, the sensors feel this as a less circulating volume in the body. In response these sensors activate many hormonal pathways to correct and normalise the blood pressure. The kidneys are instructed to excrete less water and sodium from the body to preserve the body fluids. The brain activates the thirst centrum to increase the water intake. These both lead to a higher circulating volume and thus normalise the blood pressure. This will be further discussed in the upcoming topics.
The brain also contains water and is highly sensitive to dehydration. Studies show that a slight dehydration can impair the brain performance and can lead to symptoms such as mood disorders, headaches, dizziness and tiredness.
The water contained in the kidneys is required for dissolving waste products and excreting them from the body through urine. Urinary tract infections and kidney stones are the most common medical conditions which can damage the kidneys. By drinking enough water, there is more clearing of the kidneys and this can help in preventing bacterial or stone growth in the kidneys.
Water improves the digestion process as it is essential for the production of saliva which is the first step in digestion. Besides this, water is needed for the movement of food in the intestines and for dissolving waste products that can be eliminated by the stool. Shortage of water can also lead to a high risk of constipation or hard stools.
The skin contains a large amount of water and is important for the regulation of the body temperature. When the body temperature increases, the water in the skin is pushed forward to the surface of the skin, in the form of sweat. Sweating is a process initiated to decrease the body temperature. Shortage of water can also lead to vulnerable skin conditions and can cause early wrinkling.
Dehydration can lead to several problems as mentioned above, so it is important to drink enough water to maintain a good health. The average recommendation of water intake daily (from food and fluids) is approximately 3.7 litres for men and 2.7 litres for women. A high level of water in food is found in fresh fruits and vegetables. Soups are also a good source of water.
Hydration status can be derived from the frequency and colour of the urine. A healthy urinary frequency can lie between four to ten times a day, but this can vary with age, illnesses and medication. Urine colour is normal when the urine is not dark and not strong smelling. In some groups, there is a high risk for dehydration. For instance, babies and infants are more sensitive for a small loss of fluids because they have a low weight. In elderly people, dehydration may not be properly recognised. Also, patients with illnesses involving vomiting, diarrhoea and excessive sweating (fever or athletes) require more water intake due to a high risk of water deprivation.
(Please always consult a doctor or specialist to diagnose health conditions and follow the advised plan of a qualified doctor)