In humans, dehydration can be caused by a wide range of diseases and states that impair water homeostasis in the body. These include:
External or stress-related causes
Prolonged physical activity READ MORE http://en.wikipedia.org/wiki/Dehydration
The degree of dehydration is graded according to signs and symptoms that reflect the amount of fluid lost:
In the early stages of dehydration, there are no signs or symptoms.
Early features are READ MORE http://heartspring.net/symptoms_of_dehydration.html
Dehydration occurs because there is too much water lost, not enough water taken in, or most often a combination of the two.
Diarrhea: Diarrhea is the most common reason a person loses excess water. READ MORE http://www.medicinenet.com/dehydration/article.htm
There are many things that can cause dehydration, the most common are vomiting, diarrhea, blood loss, malnutrition, and plain old failure to replenish liquids lost from sweating and urination (Not dri READ MORE http://www.symptomsofdehydration.com/