1. WATER – AN ESSENTIAL ELEMENT OF
HUMAN BODY
Mrs.A.JEEVARATHINAM
ASSISTANT PROFESSOR
V.V.VANNIAPERUMAL COLEGE FOR WOMEN
VIRUDHUNAGAR
2. INTRODUCTION
• Water is the main constituent of cells, tissues ,organs
and is vital for life .
• Approximately 70% of the body is water.
• Water has numerous roles in the human body. It acts
as a building material; as a solvent, reaction medium
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, and a
loss of 1% of body water is usually compensated within
24 hours.
4. SOURCES OF WATER
The body has three sources of water. Besides drinking
water, the following are the sources of water.
• 1. The water contained in food, eg. Fruits and
vegetables contain 80-90 percent water. Milk contain
80-88 percent. Meat contains 40-75 percent, Flour,
cracks and bread contain 5-35 percent of water.
• 2.In addition to water, ingested fluids such as ghee
(milk-based preparation). Soups and beverages also
supply essential minerals and vitamins.
• 3. Metabolic water is formed by the metabolism of
food in the body. It may amount to about 450ml per
day.
6. FUNCTIONS OF WATER
• Carrier of Food Nutrients: Every nutrient in soluble form in
water is carried from intestines to tissues through blood.
• Constituent of Liquid: Water is the major constituent of all
liquids of body as blood, urine, sweat, lymph.
• Regulate body temperature: Water helps to regulate and
control body temperature. Heat is produced when food is
burnt for energy. Water is evaporated through respiration and
sweat and body temperature is maintained normal. Body’s
heat is lost through the skin, lungs, urine and faeces.
• Safety/Security of Delicate Organs: Water is around lungs,
heart, brain which protects them from outer injury. Thus
provide security to these organs and thereby to human being.
• Water as lubricant: Water acts as lubricant in joints. Water
around joints help normal circulation process in cells. It is an
essential constituent of all the cells of the body and the
internal environment.
7. WATER BALANCE
water inputs
• Water inputs are composed of
three major sources (Table 1):
the water we drink, the water we
eat and the water we
produce. The water we drink is
essentially composed of water
and other liquids with a high water
content (85 to 490%).
The water we eat comes from
various foods with a wide range
of water content (40 to 480%). The
water we produce results
from the oxidation of
macronutrients (endogenous or
metabolic water).
• water outputs
• Water outputs. The main routes
of water loss from the body
are kidneys, skin and the
respiratory tract and, at a very
low level, the digestive system
Over a 24-h period, a sedentary
adult produces 1–2 l of
urine.
• Water is lost by evaporation
through the skin; this is called
insensible perspiration because it
is an invisible water loss
and it represents about 450 ml of
water per day in a
temperate environment.
10. Total water ouput per
day averages 2.5 liters.
This must be balanced
with water input. Our
tissues produce around
300 milliliters of water
per day through
metabolic processes. The
remainder of water
output must be balanced
by drinking fluids and
eating solid foods. The
average fluid
consumption per day is
1.5 liters, and water
gained from solid foods
approximates 700
milliliters.
DAILY FUID GAIN / LOSS
11. DEHYDRATION
Dehydration results in extreme deficiency of water and
fluids. Symptoms of dehydration are fatigue, headache,
sullenness and in extreme cases, collapse.
The steps in the progression of dehydration are as
follows.
• Thirst
• Decreasing blood volume, impaired physical
performance.
• Increased effort for physical work, nausea.
• Failure to regulate excess temperature.
• Muscle spasms.
• Failing renal function, less or no urine formed.
12. WATER INTOXICATION
Water intoxication results due to excess intake
of water. This results in an increase in the
volume of intracellular fluid. This condition can
lead to headache, nausea, vomiting, muscle
twitching and convulsions. It can even be fatal.