Human Nutrition 3(3+0)

Lesson 46 : Water, Oedema and Dehydration

Water Intake Regulation

When there is excessive loss of water from the body, the concentration of solutes in the blood becomes too high and the solutes attract water from the salivary glands, making the mouth dry and causing a person to feel thirsty.

Heat, intense physical activity (profuse sweating), diarrhoea, vomiting, and excessive urination can all cause excessive fluid loss. A runner can lose upto six cups of fluid in an hour through sweat. If the replenishment of water is not adequate, a state of dehydration can occur. Mild dehydration occurs with a loss of 5 percent or less of a person's bodily fluids, moderate dehydration is a loss of 5 to 10 percent of a person's bodily fluids, and severe dehydration is a loss of 10 to 15 percent of fluids. Severe dehydration can cause death.