Water is one of the fundamental ingredients for life on Earth and our bodies are mainly composed of it. When we are forced to go without water, things can turn nasty very fast indeed. Around 1.1 billion people lack access to safe drinking water around the world, and a total of 2.7 billion find water difficult to access for at least one month of the year but In most developed countries, accessing clean water is as simple as turning on a tap. People in these places pour gallons of it down the drain every day without a thought, as they brush their teeth, shower and flush the toilet etc. Even mild dehydration can leave us feeling more tired and less able to perform physically. How long can one survive without water ?