Dehydration occurs when your body loses too much fluid. When you stop drinking water or lose large amounts of fluids through diarrhea, vomiting, sweating, or strenuous exercise, your body's cells absorb fluid from the blood and other body tissues. When you are not drinking enough fluids, your muscles begin to get tired and you may have leg cramps or feel faint. By the time you become severely dehydrated, there is no longer enough fluid in the body to get blood to your organs. You may begin to go into shock, a life-threatening condition.

Dehydration can occur at any age, but it is most dangerous for babies, small children, and older adults.

Dehydration in babies and small children
Babies and small children have an increased risk of dehydration because:

1.A large proportion of their bodies consists of water.
2.Children have a high metabolic rate, so their bodies use more water.
3.A child's kidneys are not as efficient and do not conserve water as well as an adult's.
4.They have an immature immune system, which increases the risk of illnesses that cause vomiting and diarrhea.
5.Children often will not drink or eat when they are not feeling well.
6.They depend on their caregivers to provide them with food and fluids.