Water . . . for life!

By Cynthia T. Gayya
Science Research Specialist II, FNRI

Water is one of the most important nutrients needed by the human body for good health and survival.  It performs a vital role in digestion, absorption, metabolism, transport, and utilization of nutrients.  It also plays a role in the regulation of body temperature and excretion of toxins and waste products from the lungs, skin, and kidneys.

The average male adult body consists of 55-60% water while the female adult body consists of about 45-50% water.  Since water is the most abundant constituent of the body and functions dominantly in body processes, then it should be sufficiently supplied to carry out all its functions.

Normally, water leaves the body through sweat, perspiration, urine, bowel movement, and through other body processes that cannot be seen.  Total water loss daily is approximately 2.5 liters or about 10 cups. 

There is greater water loss on days that we perspire more, like during summer or on days that we work out.  It is important to replace lost water.

How do we know that we are getting enough water?  As a general rule, water need is dictated by our thirst and water output should balance water intake. 

 The Department of Science and Technology's Food and Nutrition Research Institute recommends an intake of 1 mL/kcal of energy expenditure.  For instance, an average adult man whose energy expenditure is 2490 kcal would require about 2.4 liters or 9-10 cups of water a day.

Experts say that water needs may vary depending on body weight, lifestyle, and environmental temperature.  The younger the individual, the greater is the requirement per body weight.  Active people require more water than sedentary ones, and people exposed to hot climates require more water intake.

The major sources of water are plain drinking water, beverages, and soups. Fruits and vegetables are also important water contributors.

[For complete information about water, as well as other nutrients for different age groups, a book on the Recommended Energy and Nutrient Intakes, Philippines 2002 edition is available at the Food and Nutrition Research Institute, General Santos Ave., Bicutan, Taguig, Metro Manila. You may also write or call: The Director, FNRI-DOST, Gen. Santos Avenue, Bicutan, Taguig, Metro Manila, Tel/Fax: 8372934, 8373164; FNRI-DOST website: http//www.fnri@dost.gov.ph]