Hello dear friends, thank you for choosing us. In this post on the solsarin site, we will talk about “percentage of water in human body pdf”.
Stay with us.
Thank you for your choice.
Water as an essential nutrient: the physiologicalbasis of hydration
, University of Lausanne, Pully, Switzerland and2Nestle ́Waters, Paris,
FranceHow much water we really need depends on water functions and the mechanisms of daily water balance regulation.
The aim ofthis review is to describe the physiology of water balance .
and consequently to highlight the new recommendations with regardto water requirements.
Water has numerous roles in the human body.
It acts as a building material; as a solvent, reactionmedium and reactant.
as a carrier for nutrients and waste products; in thermoregulation
and as a lubricant and shock absorber.
The regulation of water balance is very precise, as a loss of 1% of body water is usually compensated within 24h.
Both waterintake and water losses are controlled to reach water balance.
Minute changes in plasma osmolarity are the main factors thattrigger these homeostatic mechanisms.
Healthy adults regulate water balance with precision, but young infants .
and elderlypeople are at greater risk of dehydration.
Dehydration can affect consciousness and can induce speech incoherenc.
, extremityweakness, hypotonia of ocular globes, orthostatic hypotension and tachycardia.
Human water requirements are not based on aminimal intake.
(climate, physicalactivity, diet and so on
Water needs are based on experimentally derived intake levels that are expected to meet the nutritionaladequacy of a healthy population.
The regulation of water balance is essential for the maintenance of health and life.
On anaverage, a sedentary adult should drink 1.5l of water per day.
, as water is the only liquid nutrient that is really essential for bodyhydration.
Water is an essential nutrient for all known forms of life .
and the mechanisms by which fluid and electrolyte homeostasis is maintained in humans are well understood.
Until recently, our exploration of water requirements has been guided by the need to avoid adverse events such as dehydration.
increasing appreciation for the impinging factors that must be considered .
when attempting to establish recommendations of water intake presents us with new and challenging questions.
adverse consequences of inadequate intakes, and factors that affect fluid requirements.
For example, what are the common sources of dietary water and how do they vary by culture.
geography, personal preference, and availability, and is there an optimal fluid intake beyond that needed for water balance?
3 Minimum Water Requirements
The minimum requirement for water is the amount that equals losses.
There are numerous limitations associated with the requirement estimates used to make recommendations.
A review of the research designed to define fluid requirements of humans increases one’s appreciation of the complexity of the issue.
A multitude of intra- and inter-individual factors influence water requirements.
As stated in the 1989 Recommended Dietary Allowances .
(4) establishing a recommendation that meets the needs of all is impossible:
The primary determinant of maintenance water requirement appears to be metabolic,
(Holliday and Segar, 1957) but the actual estimation of water requirement is highly variable and quite complex.
Because the water requirement is the amount necessary to balance the insensible losses .
(which can vary markedly) and maintain a tolerable solute load for the kidneys .
(which may vary with dietary composition and other factors), it is impossible to set a general water requirement.
Factors that increase water requirements
the elderly, and people with certain illnesses may have increased fluid requirements.
and/or present additional challenges in meeting their requirements (19),
space limitations prevent adequate review of such specific populations.
Requirements and recommendations for fluid intake in hot and humid environments will be reviewed here.
because of the inordinate increase in fluid requirements that can result in such conditions .
and the large number of people worldwide who perform work in such environments.