Water is one of the most essential components of your body. Water regulates your body temperature, cushions and protects your vital organs, and aids your digestive system. It comprises 75% of all of your muscle tissue and about 10 % of all of your fatty tissue and also acts within each and every cell in your body to transport nutrients and dispel waste.  Because water constitutes more than half of the composition of your entire body, it is impossible to sustain life for more than  a maximum of 7 days without it.