Human Nutrition 3(3+0)

Lesson 45 : Water Functions and Water Balance

Body Water

The water requirement in a human body depends on

The body of an infant up to about twelve months of age, contains about 58 percent water; the bodies of children six to seven years of age is made up of about 62 percent water; bodies of teenage boys contain about 59 percent water; while in teenage girls the water content is about 45 percent. The body of an adult male is approximately 62 percent water, while that of an adult female is 51 percent water. Physically active individuals generally have more water in their bodies than those who are less physically active. Because they sweat more, active people need to replenish water more often, thus raising their body water level. A trained male runner may have up to 71 percent water in his body, while a female gymnast may have 70 percent. Obese individuals, on the other hand, have a lower percentage of water in their bodies (about 48%) because they have higher percent of fatty tissue. Morbidly obese individuals have only about 36 percent water. During old age, less water is retained in body cells. As a result, old skin looks more dry and wrinkles appear.