Question: How long can we survive without water before becoming seriously ill?

Fiona Hatch answered on 13 Mar 2012:

Really interesting question. But the answer varies a lot. The main time would be between 4 days up to 12 days without water. But this would be a severe case and you could end up collapsing and need hospital treatment at any point after 48 hours ( 2 days) of not having water.

The reason it is not an exact day is because everyone is different. Some people will need more water because they might sweat more or go to the toilet more often, so these people might not survive as long. You usually hear about people going without water for a long time after an earthquake, where they’re stuck underneath a building, one 97 year old woman was reported to go without water and food for 9 days!