1. Importance of Water
Presented by
Ena Athaide
INSTITUTE OF SCIENCE,MUMBAI

2. Functions of Water
• Cell life
• Chemical and metabolic reactions
• Transport of nutrients
• Body temperature regulation
• Elimination of waste

3. Total body water and its distribution
• Total body water : water content of the human
body, containted in the tissues, the blood, the
bones, or elsewhere.
• Body water makes up a significant fraction of
the human body, both by weight and by
volume. By weight, the average man is
approximately 60% water.

5. Fluid Compartments in the Human Body

6. Water turnover and Balance
• Water Intake:
1.Exogenous water:
 Ingested water through food and beverages.
 Range : 0.5- 5 liters .
 Increase in the osmolality increases water intake.
2. Endogenous water:
 Metabolic water
 300-350 ml derived from oxidation of food.

7. Water turnover and Balance
• Water Output
1.Urine
2.Skin
3.Lungs
4.Feces

8. Water Output
Urine
• Major route for water loss.
• 1 -2 liter/day.
• Highly regulated process depending on body
demands.
• 500 ml/day is necessary to be eliminated.

9. • Almost 180 L of water is filtered by the
glomeruli into the renal tubules everyday.
• 1-2 L is excreted as urine.
• Water excretion is regulated by kidney with the
action of ADH.
• Osmolality increases, ADH secretion increases, water
reabsorption increases from renal tubules.
• Osmolality decreases, ADH secretion decreases, water
reabsorbtion decreases.

10. Skin
• 450ml /day occurs through perspiration.
•Atmospheric temperature and humidity.
•1° rise in temperature about 15% increase in
water loss.
Lungs
• 400 ml/day is lost through expired air.
• During fever water loss through lungs is
increased.

11. Feces
• 150ml/day is lost through feces in an healthy
individual.
• Increases during Diarrhea.
The loss of water by perspiration(via skin) and
respiration(via lungs) is collectively referred to
as insensible water loss.

12. Recent Research
Should children drink more water?
the effects of drinking water on cognition in children.
• Dehydration has well-documented negative effects on adult
cognition, there is little research on hydration and cognitive
performance in children.
• They investigated whether having a drink of water improved
children's performance on cognitive tasks.
• Fifty-eight children aged 7-9 years old were randomly allocated to a
group that received additional water or a group that did not.
• Results showed that children who drank additional water rated
themselves as significantly less thirsty than the comparison group
(p=0.002), and they performed better on visual attention tasks (letter
cancellation, p=0.02; spot the difference memory tasks, ps=0.019 and
0.014).

13. References
• Importance of water in diet (http://www.nestle-
waters.com/healthy-hydration/water-fonctions-in-human-
body),viewed on 11/2/2014.
• What Is the Purpose of Water & the Function It Provides for
the Body?(http://healthyeating.sfgate.com/purpose-water-
function-provides-body-3344.html), viewed on 11/2/2014.
• The Importance Of Water And Your Health
(http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages
/Water_a_vital_nutrient?) , viewed on 11/2/2014.
• Edmonds, C. J., & Burford, D. (2009). Should children drink
more water?: The effects of drinking water on cognition in
children. Appetite, 52(3), 776-779.

14. Thank you