Water : Human body's major component   collected by tewo : (www.ethiodiasporablogspot.de)

On average, the body of an adult human being contains 60% water. Most of the water in the human body is contained inside our cells.

In fact, our billions of cells must have water to live.

The total amount of water in our body is found in three main locations: within our cells (two-thirds of the water), in the space between our cells and in our blood (one-third of the water). For example, a 70-kg man is made up of about 42L of total water. in 

28 liters is intracellular water
 14L is found in extracellular fluid of which
 3L is blood plasma,
 1L is the transcellular fluid (cerebrospinal fluid, ocular, pleural, peritoneal and synovial fluids)
 10L is the interstitial fluid (including lymph), which is an aqueous medium surrounding cells. (1)

Actually, the amount of water a body contains varies according to certain contexts: The body of a newborn is composed of more water (75%) than that of an elderly person (50%). 

for more information refer to the following link: How much water is in our Body

Why do we really need to drink 1.5 L/8 glasses (*) a day?

Water is essential and vital to human life and involved in practically all functions of the human body. Water inputs should match water outputs. Plain water should be THE choice for daily hydration as part of a healthy lifestyle.

(*)Glass of 200ml for a healthy sedentary adult living in a temperate climate.

Foods and beverages both contribute to total water intake. Nevertheless, the water that we get from food is not sufficient to maintain the water balance (Jequier, 2010). The European Food Safety Authority (EFSA) states that intake of water is predominantly through consumption of drinking water and beverages (80%) plus water contained in food (20%) - EFSA, 2010.

On average, a healthy sedentary adult living in a temperate climate needs to drink 1.5L a day (Jequier, 2010)(**).

Recommendations such as drink 8 glasses (*)/times of water a day, aim at providing easy guidance for consumers to follow in order to reach the daily recommended intake of water.

Juices or sugar-sweetened beverages can be drunk occasionally but not all day long for daily hydration purposes as they add calories, which may impact health when over consumed. As water has zero sugar and no calories, water should be THE choice for healthier hydration.

(*) Glass of 200ml for a healthy sedentary adult living in a temperate climate

(**) For an adult basis (Jequier,, 2010 - Department of Physiology, University of Lausanne, Pully, Switzerland)

infography new born adult senior percentage of water in the body