Water - a key element for our body



Water is the largest constituent of the human body: Total body water averages at 60% of body weight.1
The water content of various organs ranges from 83% in blood to only 10% in adipose tissue.2

Water content of different organs and tissue2


About two thirds of this water is located in the intracellular compartment, and one third in the extracellular compartment (plasma and interstitial fluids).1

Water is essential to our main physiological functions:

  • Water acts as a medium to support numerous metabolic reactions
  • Water, as the main component of blood, carries:
    • nutrients, hormones, and other compounds to the cells
    • metabolic waste products away from the cells, for excretion from the body3
  • Water is the solvent that assists the elimination of the soluble metabolic wastes by the kidneys, through the production of urine
  • Water ensures body temperature regulation. It is the major constituent of sweat, and through its evaporation from the surface of the skin, it helps dissipate excess body heat
Table of water content of organs and tissues in the body


  1. Armstrong LE. Hydration assessment techniques. Nutr Rev. 2005;63:S40-54.
  2. Pivarnik JM, Palmer RA. Water and electrolyte balance during rest and exercise. 1994:245-62. In Nutrition in Exercise and Sport, I. Wolinsky and J.F.Hickson, Eds. Boca Raton, FL: CRC Press.
  3. Kleiner SM. Water: an essential but overlooked nutrient. J Am Diet Assoc. 1999;99:200-6.



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Expert Working Group

Our Expert Working Group meet regularly to discuss the importance of healthy hydration and to develop strategies to encourage patients and the general public to adopt healthier hydration practices.

Prof. Max Lafontan
INSERM Unit 858, University of Toulouse, France
Prof. David Haslam
Watton-at-Stone, Hertfordshire / National Obesity Forum, UK
Prof. Hardinsyah
Bogor Agricultural University, Indonesia
Prof. Jean-François Duhamel
CHU de Caen, France
Dr. Simón Barquera
National Institute of Public Health, Cuernavaca, Mexico
Prof. Lawrence E. Armstrong
University Professor, specialist in sports physiology and expert in hydration, Connecticut, USA

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