Dehydration occurs because there is too much water lost, not enough water taken in, or most often a combination of the two. Diarrhea : In Diarrhea a person loses body water speedily. A significant amount of water can be lost with each bowel movement. Vomiting : Vomiting may result loss of fluid comparatively it is difficult for patient to replace water by drinking it. Sweat : This can also be a cause of dehydration because of warm environment, intense exercising in a hot environment, or because of fever. As a result, the body uses a significant amount of water in the form of sweat to cool itself. Diabetes : In people having higher blood sugar levels cause sugar to spill into the urine and water then follows. In this way, significant dehydration may occur. Burns : People who have burns may easily dehydrated because the body water seeps into the damaged skin. Inability to drink or digest fluids : The inability to drink and digest fluids adequately is one of the major c...