All through daily life, all of us feel thirsty. This is the brains signal that our body needs water. The brain is saying the body's dehydrated, and needs to be replenished. When your body doesn't get a great amount of water, your kidney function that eliminates wastes or toxins becomes altered. Not just this problem can occur, other major serious problems could happen. Body temperature can be no longer sufficiently controlled. You can end up with extreme temperatures, or be unable to bring your temperature up from a majorly cold temperature. Mental and physical sluggishness can happen, plus you could look groggy and drowsy or altered mental function can take place. Skin will be dry, saggy, or itchy, and muscle tone will look poor. Your metabolism and digestion process can be affected, plus fats that are stored in the body can't be metabolized. A common side effect of dehydration is inevitable constipation. You will end up having no perspiration, scanty urine, bad muscle tone or skin, and little to no saliva.