How does not drinking enough water harm your body?

Many: 1. It is a major constituent of your body. Blood- a fluid tissue& other cellular structures in the body have water. Even for hard tissues like hair, teeth water is needed. When you don't hydrate the tissues by replenishing, you loose in observable loss & unobs., tissues suffer for the chemical processes in& outside the cells and maintain vitality . 2. Toxic chemicals stay back don't get excreted wel.